OROURKE-THESIS-2013.Pdf

The Thesis Committee for Julia Marie O’Rourke Certifies that this is the approved version of the following thesis:

Environmentally Sustainable Bioinspired Design: Critical Analysis and Trends

APPROVED BY SUPERVISING COMMITTEE:

Supervisor: Carolyn C. Seepersad

Michael E. Webber

Environmentally Sustainable Bioinspired Design: Critical Analysis and Trends

Julia Marie O’Rourke, B.A.; B.S.E.

Thesis Presented to the Faculty of the Graduate School of The University of Texas at Austin in Partial Fulfillment of the Requirements

for the Degrees of

Master of Science in Engineering and Master of Public Affairs

The University of Texas at Austin May 2013

Acknowledgements

I would like to acknowledge support from a National Science Foundation Graduate

Research Fellowship and a Powers Fellowship from the University of Texas at Austin. I am also grateful for the efforts of Katherine Adams, who contributed to the GDG analysis and keyword trends analysis. Finally, I would like to thank Dr. Seepersad and the other members of the Product, Process, and Materials Design Lab for their feedback and encouragement along the way.

iv Abstract

Environmentally Sustainable Bioinspired Design: Critical Analysis and Trends

Julia Marie O’Rourke, M.S.E., M.P.Aff. The University of Texas at Austin, 2013

Supervisor: Carolyn C. Seepersad

The first section of this work critically examines thirteen of the most frequently- cited benefits of BID, using academic literature from both biology and engineering design. This analysis presents a nuanced explanation of the ways BID could improve designs and the conditions in which these improvements are expected. Hence, it provides v the theoretical foundation necessary to develop tools and methodologies that capitalize on the design opportunities found in biological organisms. The second section focuses on identifying sustainability-related trends in a pool of existing, sustainable BIDs. The type of environmental impact reduction conferred by the bioinspired feature is delineated using a set of 65 green design guidelines (GDGs) to compare the impact of the BID and a functionally-equivalent comparison product. Additionally, the general design features that impart an environmental impact reduction to the sustainable BIDs are identified, analyzed, and discussed. These results provide insight into the types of sustainability solutions that can be found using biological analogies.

vi Table of Contents

List of Tables ...... xiv

List of Figures ...... xvii

Chapter 1: Introduction ...... 1 1.1 Background ...... 1 1.1.1 Sustainable Design ...... 1 1.1.2 Bioinspired Design (BID) ...... 2 1.1.3 Sustainable BID ...... 2 1.1.4 Literature Connecting BID and Sustainability ...... 3 1.1.5 Examples of Sustainable BIDs...... 4 1.2 Thesis Motivation ...... 7 1.3 Thesis Organization ...... 8

Chapter 2: Literature Review ...... 11 2.1 Understanding and Measuring Environmental Impact ...... 11 2.1.1 Life Cycle Assessment (LCA) ...... 11 2.1.1.1 LCA Challenge #1 - Subjectivity...... 12 2.1.1.2 Environmental Ethics ...... 12 2.1.1.3 Environmental Impact Categories...... 14 2.1.1.4 LCA Challenge #2 - Detailed data are needed...... 15 2.1.2 Green Design Guidelines (GDGs) ...... 16 2.2 Previous Work ...... 18 2.2.1 BID Design Principles and Guidelines ...... 18 2.2.2 Design Principles in Biology ...... 20 2.3 Conclusion ...... 24

Chapter 3: Theoretical Study Overview ...... 25 3.1 Introduction to BID Benefits Study ...... 25 3.2 Methodology for BID Benefits Study ...... 26 3.3 Results Overview ...... 27 vii 3.4 Conclusion ...... 30

Chapter 4: Ideation-Related Archetypal Claims ...... 31 4.1 BID helps designers generate novel ideas...... 31 4.2 Quantity: Biology contains many potential analogies...... 36 4.3 Variety: Biology is diverse...... 37 4.4 Relevance: Biology solves problems engineers would like to solve...... 39 4.5 Biology solves problems differently than engineering...... 40 4.6 Conclusion ...... 43

Chapter 5: Optimization in Biology ...... 45 5.1 Biology is optimal...... 46 5.2 Biology is optimized by evolution via natural selection...... 49 5.2.1 Metaphors for ‘Evolution’ in BID Literature...... 50 5.2.2 Evolution via natural selection optimizes populations...... 52 5.2.3 Factors that Impede Optimization via Natural Selection ...... 54 5.2.4 Macroevolution: Speciation and Extinction...... 58 5.3 Biology is optimized for efficiency...... 62 5.4 Conclusion ...... 64

Chapter 6: Sustainability-Related Benefits ...... 66 6.1 Biology has withstood the test of time...... 67 6.2 Biological organisms are environmentally sustainable...... 69 6.2.1 Human-Related Environmental Impact ...... 70 6.2.2 Environmental Impact of Biology Unrelated to Humans ...... 72 6.3 Biology has specific environmental advantages...... 74 6.3.1 Biological organisms use renewable and abundant inputs...... 74 6.3.2 Biological materials are nontoxic...... 75 6.3.3 Biological organisms employ sustainable manufacturing processes...... 76 6.3.4 Biological organisms do not pollute...... 78 6.3.5 Materials in biology are recycled...... 81 6.3.6 Biology is resistant to damage...... 82 viii 6.3.7 Biology is efficient...... 83 6.4 Conclusion ...... 86

Chapter 7: BID Benefits...... 88 7.1 BIDs are optimized...... 88 7.2 BIDs are sustainable...... 89 7.2.1 BIDs are efficient...... 89 7.3 Support for All BID Benefits Claims...... 89 7.4 Caveats Common to All BID Benefits Claims ...... 90 7.4.1 The designer should intentionally try to produce a design with the desired characteristic...... 90 7.4.2 The pool of potential biological analogies should be scoped to those containing the trait of interest...... 92 7.4.3 One must focus on the relevant features of the selected analogy.93 7.4.4 How closely does the BID imitate the biological system? ...... 93 7.4.5 Will the desirable trait in biology transfer to engineering? ...... 94 7.4.6 A desirable biological trait may not continue to be desirable in a BID...... 94 7.4.7 Even beneficial features can have unintended detrimental effects.96 7.5 Conclusion ...... 97

Chapter 8: Theoretical Section Conclusion ...... 98 8.1 Summary of Findings from BID Benefits Study ...... 98 8.2 Other Claims Identified But Not Analyzed ...... 101 8.3 What counts as a biological analogy in BID? ...... 101 8.3.1 Genetically Modified Organisms and Human Selection ...... 102 8.3.2 Extinct Species ...... 102 8.3.3 Tools and Artifacts of Animals ...... 103 8.4 Future Work ...... 104 8.5 Conclusion ...... 106

Chapter 9: Research Methods to Find Trends in BIDs ...... 107 9.1 Step 1: Compile a List of BIDs ...... 108

ix 9.1.1 Breadth Search ...... 108 9.1.2 Depth Search ...... 109 9.2 Step 2: Information Collection...... 111 9.3 Step 3: Selecting Designs to Analyze ...... 112 9.3.1 Criterion 1: The design is bioinspired...... 113 9.3.2 Criterion 2: The design is feasible...... 114 9.3.3 Criterion 3: Proof of a reduced environmental impact...... 115 9.4 Analyzing Individual Designs Using Green Design Guidelines (GDGs)115 9.5 Conclusion ...... 118

Chapter 10: Data and Analysis of GDG Trends Study ...... 119 10.1 Breadth and Depth Search Results ...... 119 10.2 How BIDs Researched In Depth Fared Against Selection Criteria ....120 10.3 Design Library ...... 120 10.4 Aggregate Data from GDG Analysis ...... 122 10.5 Validation of GDG Results ...... 127 10.5.1 Independent Raters...... 127 10.5.2 Comparison of Results with Other Work...... 128 10.6 Conclusion ...... 129

Chapter 11: Additional Keyword Trends ...... 130 11.1 Methodology of Keyword Trends Study ...... 130 11.2 Identifying Keywords ...... 131 11.3 Passive Mechanisms ...... 131 11.3.1 Examples of Passive Mechanisms ...... 133 11.3.2 Potential Environmental Benefits of Passive Mechanisms .....134 11.3.3 Passive Mechanisms Conclusion ...... 135 11.4 Multifunctional Designs...... 135 11.4.1 Examples of Multifunctional Designs ...... 136 11.4.2 Potential Environmental Benefits of Multifunctional Designs137 11.4.3 Potential Environmental Benefits of Modular Designs ...... 138 11.4.4 Multifunctional Design Conclusion ...... 139 x 11.5 Optimized Geometries ...... 139 11.5.1 Examples of Optimized Geometries ...... 140 11.5.2 Potential Environmental Benefits of Optimized Geometries..141 11.5.3 Optimized Geometries Conclusion ...... 142 11.6 Validation of Keyword Trends by Analyzing 9 Sustainable BIDs .....142 11.6.1 How This Analysis Validates the Three Keyword Trends .....143 11.7 Validation of Trends Using BID Literature ...... 144 11.7.1 Passive Mechanisms ...... 144 11.7.2 Multifunctional Designs...... 145 11.7.3 Optimized Geometries ...... 146 11.8 Conclusion ...... 147

Chapter 12: Section 2 Conclusion...... 148 12.1 Summary of Section 2 ...... 148 12.2 Challenges Encountered...... 150 12.3 Future Work ...... 150 12.3.1 Analyzing More Sustainable BIDs ...... 150 12.3.2 Developing Tools and Methodologies for Sustainable BID ...152 12.3.3 Identifying Potential Benefits of BID over Other Design-by- Analogy Techniques ...... 153 12.4 Conclusion ...... 153

Chapter 13: Thesis Conclusion ...... 155 13.1 Summary of Thesis ...... 155 13.2 Discussion of Thesis ...... 156 13.3 Future Work ...... 158

Appendix A: Design Library Entries for 9 BIDs That Met All Selection Criteria and Were Analyzed Using GDGs ...... 162 A.1 Biolytix Filter ...... 163 A.2 Daimler-Chrysler Bionic Car – Shape ...... 168 A.3 Daimler-Chrysler Bionic Car – Structure ...... 171 A.4 Eastgate Centre Cooling System ...... 174 xi A.5 Interface FLOR i2 Entropy Carpet...... 177 A.6 Self-Cleaning Transparent Thin Film ...... 180 A.7 Sharklet Antimicrobial Surface ...... 183 A.8 Shinkansen 500 Series Nose Cone ...... 187 A.9 Shinkansen 500 Series Pantograph ...... 193

Appendix B: Design Library Designs with Insufficient Information ...... 197 B.1 Airbus 320 ...... 198 B.2 Baleen Water Filters ...... 200 B.3 Passive Walking Bipedal Robot ...... 203 B.4 Calera Cement ...... 206 B.5 Geckel...... 211 B.6 HotZone Radiant Heater...... 214

Appendix C: Design Library Designs Eliminated Using 3 Criteria ...... 217 C.1 Crystal Palace in London ...... 218 C.2 Eiffel Tower ...... 220 C.3 Velcro ...... 222

Appendix D: Green Design Guidelines Adapted From Telenko [61] ...... 225

Appendix E: 128 Sources Analyzed in BID Benefits Study...... 227

Appendix F: BIDs Found from Breadth and Depth Searches...... 235

Appendix G: Comparison of the Environmental Impact of BIDs and Competitors Using GDGs with Justification ...... 241 G.1 Biolytix...... 241 G.2 Daimler-Chrysler Bionic Car – Shape ...... 242 G.3 Daimler-Chrysler Bionic Car – Structure ...... 243 G.4 Eastgate Centre Cooling System ...... 244 G.5 Interface FLOR i2 Entropy Carpet...... 245 G.6 Self-Cleaning Transparent Thin Film ...... 246 G.7 Sharklet Antimicrobial Surface ...... 248 G.8 Shinkansen 500 Series Nose Cone ...... 249 xii G.9 Shinkansen 500 Series Pantograph ...... 249

Appendix H: Analysis of 9 Sustainable BIDs for Passive Mechanisms, Multifunctional Designs, and Optimized Geometries ...... 250 H.1 Biolytix...... 250 H.2 Daimler-Chrysler Bionic Car – Shape ...... 250 H.4 Eastgate Centre Cooling System ...... 251 H.5 Interface FLOR i2 Entropy Carpet...... 252 H.6 Self-Cleaning Transparent Thin Film ...... 252 H.7 Sharklet Antimicrobial Surface ...... 253 H.8 Shinkansen 500 Series Nose Cone ...... 253 H.9 Shinkansen 500 Series Pantograph ...... 254

References ...... 255

xiii List of Tables

Table 1: LCA midpoint categories and damages to environment [51] ...... 15 Table 2: “Biomimetic design guidelines with examples of corresponding bio-inspired characteristics and the percentage of reviewed products that display

them” from Wadia and McAdams [62]...... 19

Table 3: Biomimetic design principles from Wadia [63] ...... 20 Table 4: Efficiencies of Common Anthropogenic and Natural Energy Conversion

Efficiencies from Tester [221] and adapted from Smil [223]...... 85

Table 5: Summary of Findings from Theoretical BID Benefits Study...... 98

Table 6: Design Selection Criteria ...... 113

Table 7: The first six BIDs considered for analysis...... 119

Table 9: Summary of GDG Analysis, Organized by both GDG and BID...... 123

Table 10: GDGs met better by the BIDs...... 124 Table 11: Examples of passive mechanisms in non-BID engineered systems, BIDs,

and biological systems...... 133 Table 12: Examples of multifunctional designs in non-BID engineered systems, BIDs,

and biological systems...... 136 Table 13: Examples of optimized geometries in non-BID engineered systems, BIDs,

and biological systems...... 140

Table 14: Keyword trends found in sustainable BIDS...... 142 Table 15: Summary of the GDGs most frequently met better by the 9 sustainable

BIDs...... 149

Table 16: Summary of the keyword trends found in the 9 sustainable BIDs...... 149

Table 17: Claims analyzed in Chapter 6 with related GDGs...... 160

xiv Table 18: 128 Sources Analyzed in BID Benefits Study...... 227

Table 19: BIDs Found from Breadth and Depth Searches...... 235

Table 20: The GDGs met better by Biolytix than by its competitor...... 241 Table 21: The GDGs met better by the shape of the bionic car than by its competitor.

...... 242 Table 22: The GDGs met better by the structure of the bionic car than by its

competitor...... 243 Table 23: The GDGs met better by the Eastgate Centre’s cooling system than by its

competitor...... 244

Table 24: The GDGs met better by Entropy carpet than by its competitor...... 245 Table 25: The GDGs Entropy tiles might meet better than standard carpet tiles in

some scenarios...... 246 Table 26: The GDGs met better by the self-cleaning surface than by its competitor.

...... 246 Table 27: The GDGs met worse by the self-cleaning surface than by its competitor.

...... 247 Table 28: The GDGs that might be met better by the self-cleaning surface than by its

competitor, but ambiguity exists...... 247

Table 29: The GDGs met better by Sharklet than by its competitor...... 248 Table 30: The GDGs where it is unclear whether Sharklet or its competitor is

environmentally superior...... 248 Table 31: The GDGs met better by the Shinkansen nose cone than by its competitor.

...... 249 Table 32: The GDGs met better by the Shinkansen pantograph than by its competitor.

...... 249 xv Table 33: Keyword Trends Analysis for Biolytix...... 250

Table 34: Keyword Trends Analysis for the Shape of the Bionic Car...... 250

Table 35: Keyword Trends Analysis for the Structure of the Bionic Car...... 251

Table 36: Keyword Trends Analysis for Eastgate Centre’s Cooling System...... 251

Table 37: Keyword Trends Analysis for Entropy Carpet...... 252

Table 38: Keyword Trends Analysis for the Self-Cleaning Surface...... 252

Table 39: Keyword Trends Analysis for Sharklet Antimicrobial...... 253

Table 40: Keyword Trends Analysis for the Shinkansen 500 Series Nose Cone.253

Table 41: Keyword Trends Analysis for the Shinkansen 500 Series Pantograph.254

xvi List of Figures

Figure 1: Sustainable BID lies at the intersection of sustainable design and BID.. 3 Figure 2: The energy efficient cooling system in Eastgate Centre [35] is a sustainable BID inspired by cooling in termite mounds that replaces a standard

industrial air conditioner...... 5

Figure 3: Shape evolution from boxfish to car [40]...... 6

Figure 4: Self-cleaning surface inspired by the surface chemistry of the lotus leaf.7

Figure 5: The relation of midpoint categories and damage indicators [51]...... 14

Figure 7: Life’s Principles, the 2009 version from the Biomimicry Guild [64] ....22

Figure 6: Life’s Principles, the 2011 version from the Biomimicry Group [65] ...23 Figure 8: Schematic depicting the 13 archetypal claims found and analyzed in this

study...... 28 Figure 9: Spectrum depicting the varying extent to which authors affirm the

archetypal claims found in BID literature study...... 29 Figure 10: Mindmap of ideation-related archetypal claims concerning benefits of

BID...... 31

Figure 11: “How problems are solved in (a) technology and in (b) biology” [71].42

Figure 12: Mindmap of optimization-related archetypal claims...... 45

Figure 13: All archetypal claims and sub-claims related to sustainability...... 67 Figure 14: Comparison of carbon-dioxide equivalent emissions from Clark [183],

including those from camels and cows...... 79 Figure 15: Comparison of methane emissions from Wilkinson et al. [186], including

those from sauropods and cows...... 80

Figure 16: Archetypal claims related directly to characteristics of BIDs...... 88

xvii Figure 17: Overall research methodology for identifying sustainable design solutions

in existing BIDs...... 107 Figure 18: A snowball sampling search starting with the term “dolphin skin boat hulls” is more likely to return results related to dolphins or boat hulls than a randomly-selected and unrelated BID, like “gecko-inspired

adhesives.”...... 111

Figure 19: Example GDG comparison...... 117 Figure 20: Trends related to the GDGs most frequently met better by the BIDs than

their competitors...... 126 Figure 21: Depiction of a potential design tool that could be used to find examples of

sustainable BIDs that meet a particular GDG...... 152

xviii Chapter 1: Introduction

Within the bodies of living organisms are multitudes of sustainable design solutions that engineers have yet to master. Through the use of tailored sustainable bioinspired design (BID) tools and methodologies, engineers could access and apply this body of biological knowledge to reduce the environmental impact of engineering designs. However, the underlying theory of BID must be more thoroughly fleshed out – and a clearer understanding of the types of sustainability solutions present in biology must be achieved – before such tools and methodologies can be developed. The goal of this thesis is to tackle both issues and, consequently, lay the foundation for sustainable BID. Chapter 1 provides the necessary background information and introduces this effort. First, an overview of sustainable design, BID, and sustainable BID is provided, with a discussion of the connection between biology and sustainable design and examples of existing sustainable BIDs. Next, the motivation for both the theoretical and empirical studies is presented. Finally, the organization of the thesis is detailed.

1.1 BACKGROUND

In this section, background information on sustainable design, BID, and sustainable BID is provided. This includes a discussion of the literature connecting BID and sustainability and a presentation of three examples of sustainable BIDs.

1.1.1 Sustainable Design

Human activity is dramatically changing the global environment [1].

Anthropogenic environmental changes harm other organisms [2,3], lower biology’s ability to adapt to future evolutionary stresses [4], and reduce the quality of life for future generations [5]. These changes are caused by a number of factors, including: (1) human overproduction and overconsumption [6] and (2) poor design [7], or “the unintended 1 consequences of [human] activities as engineers” [8]. Environmentally sustainable design, hereafter referred to as ‘sustainable design,’ is aimed at the second of these two causes of anthropogenic environmental change and is focused on helping engineers lower the environmental impact of their designs.

1.1.2 Bioinspired Design (BID)

BID is a design methodology that uses biological organisms as analogies for engineered designs. Some authors have distinguished between different design methodologies that incorporate biological analogies, using terms such as ‘bioinspired design,’ ‘biomimicry,’ ‘bionics,’ and ‘biognosis’ to make these distinctions. Although the differences between these terms may be important in some contexts, here they are combined as they are in numerous popular [9,10] and academic sources [11-14], and all are referred to as BID.

1.1.3 Sustainable BID

Many sustainable design solutions in biology are worth imitating. For instance, spiders manufacture silk with desirable engineering properties at “close to ambient temperatures and pressures using water as the solvent” [15]; vortices created when water is ejected through the velum of jellyfish minimize energy consumption during swimming

[16]; the water-repellent surfaces of lotus leaves clean effectively without the use of hazardous chemicals [17]; and the texture of shark skin reduces frictional drag [18]. The imitation of solutions, such as these, in engineering design could contribute to the development of products with reduced environmental impacts. The process by which biological analogies are used to produce engineering designs with lower environmental impacts is referred to here as sustainable BID.

2 Sustainable BID lies at the intersection of sustainable design and BID, drawing theories and methodologies from both fields.

Figure 1: Sustainable BID lies at the intersection of sustainable design and BID. Photo credits: [19,20].

1.1.4 Literature Connecting BID and Sustainability

A wide range of sources indicate that biological systems could be, and are being, used as analogies in design to reduce the environmental impact of products. Both science- related works for the general public and academic literature indicate this is the case. Benyus states in Biomimicry: Innovation Inspired by Nature:

[L]ife has learned to fly, circumnavigate the globe, live in the depths of the ocean and atop the highest peaks, craft miracle materials, light up the night, lasso the sun’s energy, and build a self-reflective brain. Collectively, organisms have managed to turn rock and sea into a life-friendly home.... In short, living things have done everything we want to do, without guzzling fossil fuel, polluting the planet, or mortgaging their future. What better models could there be? [21]

This message – that the biological world has something to offer to the sustainable design community – is widely accepted by the non-academic community. The acceptance of the message can be observed through its frequent repetition on science-related websites and blogs, and in newspaper and magazine articles. Titles such as “Biomimicry Offers 3 Sustainable Solutions Inspired by Nature” [22] and “How Biomimicry Drives Sustainability: From Fish-Inspired Wind Turbines to the Future of 3-D Printing” [23] drive home this connection for the general public. The connection between bioinspiration and sustainable design is also echoed in scientific literature. For instance, Nagel states:

Biological organisms, phenomena and strategies… are exemplary systems that provide insight into sustainable and adaptable design… engineers can not only mimic what is found in the natural world, but also learn from those natural systems to create reliable, smart and sustainable designs [14].

Additionally, journal articles such as “Bio-inspired Constructs for Sustainable Energy Production and Use” [24] and “Sustainable and Bio-inspired Chemistry for Robust Antibacterial Activity of Stainless Steel” [25] link BID to sustainability in their titles. In a number of cases, sources define BID as being inherently linked to sustainability. For instance, sources state that BID is “a design discipline that seeks sustainable solutions by emulating nature’s time-tested patterns and strategies” [26], and that BID “tak[es] inspiration from nature to create a product that’s friendly to the environment” [22]. However, it is not safe to assume that all BIDs are sustainable by virtue of the fact that they are bioinspired. Life cycle assessments of BIDs from Raibeck et al. [27] and Reap et al. [28] have shown that BIDs are not sustainable by default, and that the entire product life cycle must be considered to determine whether a particular bioinspired feature will confer a sustainability advantage to a design.

1.1.5 Examples of Sustainable BIDs

A number of compelling examples are commonly cited when discussing the environmental benefits of using biological analogies in the design process, such as the

4 cooling system in Eastgate Centre, the shape of the Daimler-Chrysler bionic concept car, and the chemistry of self-cleaning thin films. These three examples will now be used to illustrate the potential for sustainable BID. Eastgate Centre is a shopping center and office building in Zimbabwe that has a passive cooling system [29-32] inspired by cooling in termite mounds [30,33]. The building and its biological analogy are depicted in the figure below. Instead of a traditional industrial air conditioning system, which involves substantial equipment and electricity consumption, Eastgate Centre achieves the same amount of cooling using only fans [29-31], representing substantial energy savings [32]. This energy and equipment reduction is possible because the geometry of the building promotes the flow of hot air out of chimneys on the roof, drawing in cooler air at ground level [29-31], similar to the way termite mounds remain cool throughout the day [34]. This passive cooling allows for a substantial reduction in the amount of energy consumed by the building [32].

Figure 2: The energy efficient cooling system in Eastgate Centre (right) [35] is a sustainable BID inspired by cooling in termite mounds (center) that replaces a standard industrial air conditioner (left). Photo credits: [36-38].

Similarly, the bioinspired shape of the Daimler-Chrysler bionic concept car confers an environmental advantage. The evolution of the car from the shape of the 5 boxfish is shown in the figure below. Surprisingly, the boxy shape of the appropriately- named boxfish is aerodynamic, promoting the formation of favorable vortices that stabilize the boxfish and result in energy savings during swimming [39,40]. Because the Daimler-Chrysler concept car is shaped similarly, it experiences less drag [41] – and consequently consumes less fuel – than a car with a standard profile.

Figure 3: Shape evolution from boxfish to car [40].

Finally, self-cleaning surfaces are another example of BIDs that have an environmental advantage as a consequence of their bioinspired features. These surfaces, and the lotus leaves that inspired them [42], are shown in the figure below. The self- cleaning process in the lotus leaf occurs as result of its hydrophobic (water-repelling) surface chemistry that causes water to bead on the leaf. When water beads, and subsequently rolls off the surface of the leaf, debris on the surface is pulled into the bead of water and rolls off as well [17]. When this surface chemistry is imitated on manmade products, objects that would otherwise need to be cleaned using large volumes of pressurized water and toxic chemicals can instead be cleaned using a small volume of water spayed as a mist onto the part [27]. Consequently, less energy and water are consumed [27,43], and the use of toxic and non-biodegradable materials is avoided.

Figure 4: Self-cleaning surface (left) inspired by the surface chemistry of the lotus leaf (right). Photo credits: [44,45].

More detailed information from peer-reviewed sources and analysis of the environmental impact of these three designs, and many others, can be found in Appendices A-C.

1.2 THESIS MOTIVATION

While many sources proclaim the environmental benefits of BID, and while the examples of sustainable BIDs are compelling, much analysis is lacking in existing literature regarding the relationship between BID and sustainable design. First, empirical evidence that the use of biological analogies produces environmental benefits in general is lacking; there is no evidence to suggest that using a biological analogy would always – or would even likely – result in more sustainable aspects of a final design. Instead, there is evidence that the use of biological analogies in design does not, as a rule, result in the reduced environmental impact of products [28]. Rather than necessarily having a smaller environmental impact than competitors by virtue of the fact that they have a bioinspired feature, the examples of sustainable BIDs cited above may be more sustainable than competitors by chance, just as designs developed

7 using analogies from other engineered products are sometimes more sustainable than alternatives. Second, sources touting the environmental benefits of BIDs rarely acknowledge that these benefits are frequently one side of an environmental tradeoff, and are many times necessarily paired with negative environmental impacts in other phases, or even the same phase, of the product’s life cycle. For instance, self-cleaning surfaces reduce the environmental impact during cleaning but are likely to increase the impact in manufacturing [27].

Finally, the logic explaining why the use of biological analogies in the design process would lead to more sustainable products, or to any other claimed benefit of BID, is almost entirely absent from the literature, with the exception of vague references to the evolutionary process, mention of nature’s ‘3.8 billion years of R&D’, or platitudes about ‘how magnificently efficient’, etc., nature is – without any insight into the details of what, why, and how something is efficient, for example.

These three issues indicate a need, first, to develop the underlying theory of BID and understand BID’s benefits, and second, to study why and how some biological analogies have aided in the reduction of the environmental impact of products. Having this knowledge would enable engineers to more effectively use biological analogies to generate sustainable designs.

1.3 THESIS ORGANIZATION

This work is organized into two main sections: (1) a theoretical section analyzing the claimed benefits of BID, and (2) an empirical section examining the ways in which BID can be used to generate environmentally sustainable designs. Chapter 2 presents necessary background information for both. It discusses two tools to understand and

8 measure the environmental impact of products - life cycle assessment (LCA) and green design guidelines (GDGs). It also provides a discussion of previous research focused on the analysis of many biological systems or BIDs together. Section 1 seeks to answer the questions: In what sense is BID ‘beneficial’ compared to other ideation techniques? What desirable traits can be found in biological organisms, and which of these traits transfer to BIDs? To what extent are BIDs and the biological systems that inspire them ‘novel’, ‘optimized’, ‘efficient’, or ‘sustainable’?

The answers to these questions provide insight into the potential role of BID in improving engineering designs. By qualifying and clarifying these claims in the context of biological evidence, Chapters 3 through 8 contribute to the theoretical foundation for BID and provide guidance to researchers developing design tools and methodologies to enhance engineered products and systems using BID. Chapter 3 presents the methodology of the theoretical study, along with an overview of the claims identified and analyzed. Chapter 4 examines ideation-related claims. Chapter 5 looks at optimization-related claims. Chapter 6 focuses on efficiency- related claims. Chapter 7 considers sustainability-related claims, and Chapter 8 summaries the conclusions of the theoretical study. The central question posed in Section 2 is: ‘What trends are present in existing, sustainable BIDs?’ or, in other words, ‘When the use of a biological analogy has been confirmed to have provided a true environmental advantage to a design, what types of design features have been transferred?’ As will be discussed in Chapter 7, not all desirable biological features can be transferred to engineering designs and retain their desirable characteristics. Section 2 seeks to better understand the types of traits that do indeed successfully transfer and result in an environmental impact reduction in the final design. 9 Chapter 9 presents the research methods used in an empirical study aimed at uncovering these sustainability-related trends. Chapter 10 contains the data collected in the study and an analysis of the aspects of environmental impact that were reduced in the sustainable BIDs. Chapter 11 discusses the overarching principles uncovered and the types of characteristics that were observed to successfully transfer from biology to engineering, along with an analysis of the prevalence of these characteristics in biology. Chapter 12 concludes the section, presenting a summary of the findings and significance of the study.

Chapter 13 presents a discussion of the thesis as a whole, particularly the ways in which biology can provide insight into environmentally sustainable product design. It presents potential avenues for future work that draw from both the theoretical findings of Section 1 and the empirical results from Section 2, and concludes with a summary of the contributions of the thesis.

10 Chapter 2: Literature Review

Chapter 2 delves into the tools and findings from both the sustainable design and BID research communities. First, it presents an overview of two tools to measure the environmental impact of products – life cycle assessment (LCA) and green design guidelines (GDGs) – and provides an ethical framework for understanding environmental impact. Second, it presents a discussion of previous work from the BID research community, focused on the results of other authors’ analyses of many biological systems or BIDs together and the abstraction of design principles from these analyses.

2.1 UNDERSTANDING AND MEASURING ENVIRONMENTAL IMPACT

A number of tools and findings from the sustainable design community related to understanding and measuring environmental impact are brought to bear in this work, especially those related to life cycle assessment (LCA) and green design guidelines (GDGs).

2.1.1 Life Cycle Assessment (LCA)

Effective LCA tools and techniques quantify the environmental impact of a product throughout its life cycle “from raw material acquisition through production, use, end-of-life treatment, recycling and final disposal” [46]. ISO standards 14040:2006 and 14044:2006 address, respectively, the principles and framework of LCA, and the requirements and guidelines for LCA [47]. These standards are intended to help quantitatively assess and compare the environmental impacts of functionally-equivalent competing products [46].

11 2.1.1.1 LCA Challenge #1 - Ethics and values introduce subjectivity.

One of the main challenges associated with LCA is that the outcome is influenced by personal values during goal and scope definition [48,49], and in the weighting of different types of environmental damages [3,46,50,51]. These value differences generate a lack of consensus on how to properly conduct LCAs [50], which can lead to conflicting results. Consequently, it is important to provide a basic explanation of the environmental value system and ethical perspective adopted when conducting an LCA [48]. Other types of tools that provide insight into the environmental impact of designs, such as GDGs, likewise involve personal value judgments. Hence, although an LCA will not be presented in this work, it is important to identify the ethical perspective and environmental value system adopted here so that the analysis of environmental impact using GDGs will be as transparent and objective as possible.

2.1.1.2 Environmental Ethics

The field of environmental ethics examines the moral and ethical role of the environment [5,52,53]. One of the central points of contention among experts in this field concerns whether the environment and non-human biological organisms are valued as ends in themselves or only as a means for human benefit. The Stanford Encyclopedia of Philosophy sets up this distinction as follows:

It is often said to be morally wrong for human beings to pollute and destroy parts of the natural environment and to consume a huge portion of the planet’s natural resources. If that is wrong, is it simply because a sustainable environment is essential to (present and future) human well-being? Or is such behavior also wrong because the natural environment and/or its various contents have certain values in their own right so that these values ought to be respected and protected in any case? [53]

12 The way one answers these questions can have a profound implication on how one assesses the environmental impact of products through LCA and other environmental assessment techniques. Some widely-accepted documents indicate that the environment and biological organisms should be valued as ends in themselves. For instance, The Earth Charter states: “all beings are interdependent and every form of life has value regardless of its worth to human beings” [6], and the preamble to the United Nation’s Convention on

Biological Diversity acknowledges “the intrinsic value of ecological diversity” [54].

However, most people in the Western world have adopted an anthropocentric ethical perspective and do not accept that the environment has intrinsic value [5,53]. Consequently, many sources aimed at achieving scientific or political consensus present an ethical perspective that focuses on the instrumental value of the environment for human beings, i.e. the “ecological, genetic, social, economic, scientific, educational, cultural, recreation, and aesthetic” value that the environment provides [54]. This approach has been taken by a number of authors in science [5], government [4], and international organizations such as the United Nations [54-56]. Because it is widely accepted that the environment possesses instrumental value for humans, and because this stance on environmental ethics appears to be taken by many authors aimed at impartiality, that perspective has been adopted here. This document adopts an anthropocentric view of environmental ethics, and accepts that human beings have moral obligations to avoid harming other human beings through negative environmental impacts, while also accepting moral environmental responsibilities towards future generations. The negative effects environmental change has on human beings will be emphasized, and environmental changes that negatively affect other

13 organisms will be addressed in terms of how these changes negatively affect the benefits humans glean from these organisms.

2.1.1.3 Environmental Impact Categories

Because different people have different opinions on how environmental assessments should be scoped, it is also important to define what is meant by an ‘environmental impact.’ Here, the framework used to define environmental impact is borrowed from a document [51] written by an international task force nominated by the United Nations Environmental Program (UNEP) and the Society of Environmental Toxicology and Chemistry (SETAC). It is intended to provide a common framework for life cycle impact assessment that is universally accepted [51]. The paper relates ‘environmental impact pathways’ to ‘damage indicators’; this relation is shown in the diagram below.

Figure 5: The relation of midpoint categories and damage indicators [51].

14 The ethical perspective adopted here focuses on the instrumental value of the environment (including the biotic and abiotic natural environment, natural resources, and the man made environment) and both the intrinsic and instrumental values of human life. Hence, the understanding of environmental impact adopted here is the same as that discussed in Jolliet et al. [51], with the exception that damages related to the intrinsic value of the biotic natural environment and the abiotic natural environment (the fourth and seventh column in the chart below, respectively) are not considered.

Table 1: LCA midpoint categories and damages to environment [51]

2.1.1.4 LCA Challenge #2 - Detailed data are needed.

A second main challenge associated with LCA is that a substantial amount of detailed data concerning the product’s components, materials, and manufacturing processes is needed for the analysis to be accurate [57]. As a consequence, it is difficult to conduct LCA during conceptual design, when little detailed information about a design 15 is known. This requirement poses a major challenge for the field of sustainable product design because most of a product’s environmental impact is determined during conceptual design, when decisions are made regarding product performance and materials [58], meaning that sustainable design techniques are most effective in the early stages of new product design [59]. For example, a study of thirty companies showed that those that implemented sustainable design practices before product specification were able to see larger environmental impact reductions in their products than companies that used sustainable design methods at a later stage in the design process [60].

2.1.2 Green Design Guidelines (GDGs)

It is critical to have tools to assess the environmental impacts of concepts during the early phases of product design, so that more sustainable concepts can be selected. Telenko [61] has compiled a list of 65 green design guidelines (GDGs) to help address this problem. The GDGs are organized into six categories: (1) sustainability of resources, (2) healthy inputs and outputs, (3) minimum use of resources in production and transportation, (4) energy efficiency of resources during use, (5) the appropriate durability of the product and components, and (6) disassembly, separation, and purification [61]. The guidelines help designers think about all aspects of the life cycle that could potentially generate an environmental impact, allowing them to make better- informed design decisions concerning sustainability during conceptual design. A list of these guidelines is provided in Appendix D. The GDGs are similar to the midpoint categories presented in Jolliet et al. [51] in that they look at a wide range of environmental impacts over the life cycle. However, the GDGs are specifically focused on assessing the environmental impact of products, with guidelines such as “GDG#6: specifying mutually compatible materials and fasteners for

16 recycling,” whereas the midpoint categories are more general, e.g. ‘Ozone depletion’. Hence, the midpoint categories are more widely applicable, but they provide significantly less guidance to designers working on specific problems. Additionally, the GDGs do not define ‘environmental impact’ or explain how one ought to measure environmental impact. For example, GDG #12: “Including labels and instructions for safe handling of toxic materials” recommends that a designer consider how toxic materials will be handled and how to communicate to the handlers what should be done; it does not imply that the process of label-making and label-using is good for the environment. Having labels (and instructions) in this instance is presumed to be better for the environment because it is associated with ‘safer’ handling of toxic materials, presumably equivalent to fewer harmful releases of toxic materials to the environment. As in LCA, the GDGs must be interpreted using a definition of environmental impact derived from personal value systems. For instance, GDG #12 does not define ‘safe’ handling of toxic materials. The dumping of materials toxic to humans in an area where humans are likely to encounter the substance is presumably not ‘safe,’ but is it ‘safe’ to release materials that are toxic to ecosystems but nontoxic to humans? Is the release of materials damaging to man-made devices but nontoxic to humans ‘safe’? In the analysis in Chapter 10 of this thesis, the environmental impact of design concepts are compared to one another using the GDGs and the modified interpretation of ‘environmental impact’ provided in the Jolliet et al. [51] paper. The use of this definition coupled with the GDGs has a significant influence on the results of the empirical portion of the study. For instance, noise is not explicitly accounted for in the GDGs, but it is listed as a ‘midpoint category,’ thereby supporting the decision to account for noise from the Shinkansen train as ‘noise pollution’ under GDG #8: “Installing protection against the release of pollutants and hazardous substances,” even though the intent of the guideline 17 may have actually been directed at more traditional types of pollutants. This also comes into play for products like Sharklet, whose prime environmental advantage is that it does not contribute to the evolution of antibiotic-resistant bacteria. This type of environmental impact falls under the midpoint category ‘Species and organism dispersal,’ but is not directly addressed in the GDGs.

2.2 PREVIOUS WORK

In addition to the work discussed above focused on understanding and measuring environmental impact, a number of studies from the BID research community are closely related to the findings discussed throughout this thesis. Below, results from Wadia and McAdams [62], Wadia [63], Vincent et al. [11], and Biomimicry 3.8 and its affiliated organizations and founders [21,64,65], related to the discovery of trends in BIDs and biological organisms, are presented. These findings will be referenced throughout this thesis, particularly in Chapters 10 and 11, focused on the identification of sustainability- related trends in existing, sustainable BIDs, where these findings serve to validate the results of the empirical studies.

2.2.1 BID Design Principles and Guidelines

A 2010 paper from Wadia and McAdams [62] and Wadia’s 2011 thesis [63] both present studies where 20 and 23 BIDs were analyzed, respectively, to “identify the inherent characteristics that make the designs robust to their environment” and generate biomimetic design guidelines [62]. The biomimetic design principles uncovered by

Wadia and McAdams [62] are presented in the table below.

18 Table 2: “Biomimetic design guidelines with examples of corresponding bio-inspired characteristics and the percentage of reviewed products that display them” from Wadia and McAdams [62].

Wadia [63] generated slightly different results, which are in the table below, organized into what he refers to as ‘super groups’:

19 Table 3: Biomimetic design principles categorized into super groups from Wadia [63]

Some of the biomimetic design guidelines extracted in both studies provide verification for the results of the studies presented in Chapters 10 and 11. Additionally, Wadia’s thesis [63] analyzes 5 of the same BIDs analyzed in Section 2 of this work – Eastgate Centre, the shape of the Daimler-Chrysler bionic concept car, the nose cone of the Shinkansen train, the lotus-inspired self-cleaning surface, and the Shinkansen’s pantograph. Hence, the notes and analysis from those works can be used as validation for the analysis of specific designs, the results of which are presented in Chapters 10 and 11.

2.2.2 Design Principles in Biology

Additionally, a number of authors have either formally or informally studied samples of biological organisms to extract trends or ‘design principles.’ Work from 20 Vincent et al. [11] and Biomimicry 3.8 and its affiliated organizations and founders [21,64,65] is discussed below. Vincent et al. [11] conducted a study comparing the principles illustrated by problem solutions in 500 biological phenomena with those from TRIZ, and found that there is only a 12% overlap between these principles in biology and engineering. They also found that biological systems solve problems using information- and structure-based solutions, whereas problems encountered in technology are typically solved though energy manipulation [11]. This implies that mechanisms in biology may be less likely to solve problems with the use of energy than typical engineering designs. Additionally, organizations and people connected to what is currently called Biomimicry 3.8 have released a number of non-academic publications with varying accounts of biological design principles. Three such accounts are presented below and are of particular interest because Biomimicry 3.8 is also focused on the development of sustainable design solutions through the use of biological analogies [66].

Benyus, co-founder of Biomimicry 3.8, details “a canon of nature's laws, strategies, and principles” in her influential 1997 book Biomimicry: Innovation Inspired by Nature [21], encompassing the following nine items: (1) “Nature runs on sunlight”; (2) “Nature uses only the energy it needs”; (3) “Nature fits form to function”; (4) “Nature recycles everything”; (5) “Nature rewards cooperation”; (6) “Nature banks on diversity”; (7) “Nature demands local expertise”; (8) “Nature curbs excesses from within”; and (9) “Nature taps the power of limits” [21]. It is not clear how she arrived at this list; she states only that it was “divine[d]” from the notebooks of ecologists [21]. Additionally, two more recent versions of a list of traits found in biology, known as “Life’s Principles” – a 2009 version from the Biomimicry Guild [64] and a 2011 version from the Biomimicry Group [65] – are provided below. 21

Figure 7: Life’s Principles, the 2009 version from the Biomimicry Guild [64]

Figure 6: Life’s Principles, the 2011 version from the Biomimicry Group [65]

Some of the principles put forth in Biomimicry 3.8-affiated documents agree with the results presented in Chapters 10 and 11 of this work and will be discussed further there.

23 2.3 CONCLUSION

Chapter 2 has provided a wide range of background information concerning the understanding of ‘environmental impact’ adopted here, and the measurement of environmental impact using LCA and GDGs. Additionally, an overview of related work that identified design principles in BIDs and biological organisms was provided. Now that this background information is in place, it is possible to shift the focus towards Section 1, which presents a theoretical study of the potential benefits of BID.

24 Chapter 3: Theoretical Study Overview

Chapter 3 introduces Section 1 and the theoretical study of BID benefits. It presents an introduction to the BID benefits study, the methodology of the study, and an overview of the claims identified and analyzed.

3.1 INTRODUCTION TO BID BENEFITS STUDY

Many academic and non-academic sources include accounts of the benefits of

BID. These accounts invoke a small set of claims that recur throughout the literature, concerning the characteristics of BIDs and the biological systems that inspire them. Below are four such accounts found from academic sources, provided to show the diversity of benefits cited. These and 25 other accounts that provide an extended explanation of the benefits of BID are listed in and are identified with an asterisk Appendix E. 1. Nagel et al. [67] in the Journal of Mechanical Design state:

The designs of the biological world allow organisms to survive in nearly all of earth’s challenging environments filling niches from under-sea volcanic vents, tundras both frozen and desolate, poisonous salt flats, and deserts rarely seeing rain. Nature’s designs are the most elegant, innovative, and robust solution principles and strategies allowing for life to survive many of the earth’s challenges. Biomimetic design aims to leverage the insight of the biological world into the engineered world.

2. Wilson and Rosen [12] in IDETC/CIE 2007 claim:

With design, engineers strive to produce more economical and efficient solutions to problems. The duality between engineering and biological systems exists in the pursuit of this efficiency. Nature has been on this search for many, many years. In order to survive, natural systems must be efficient, using minimal amounts of energy as a source for efficiency. In nature, where the fittest survive, all organisms compete with each other for available energy.

25 3. Ball [68] in Nature explains:

[N]ature does not employ exotic materials, nor extreme energies or high pressures. The living world comes almost with a guarantee of economy, for that is evolution’s exigency. Maximum return for minimal (metabolic) outlay: this is the stipulation that keeps nature lean and, in some sense, optimal.

4. Finally, Bar-Cohen [69] in Biomimetics: Biologically Inspired Technologies maintains:

After billions of years of evolution, nature developed inventions that work, which are appropriate for the intended tasks and that last. The evolution of nature led to the introduction of highly effective and power efficient biological mechanisms. Failed solutions often led to the extinction of the specific species that became a fossil. In its evolution, nature archived its solutions in the genes of creatures that make up the terrestrial life around us. Imitating nature’s mechanisms offers enormous potentials for the improvement of our life and the tools we use… Benefits from the study of biomimetics can be seen in many applications, including stronger fiber, multifunctional materials, improved drugs, superior robots, and many others.

In Section 1, a study examining such accounts is presented. As can be seen from the examples above, there is a wide range of claimed benefits authors make on behalf of the BID process – everything from leveraging the innovative and lasting solutions found in biology to assisting in developing efficient and multifunctional engineering designs. It will be shown that upon a deeper inspection of the literature, some of these claims only hold true in some instances and are disputed within the BID research community. The results of this study provide insight into the potential of BID and, hence, guidance to researchers working to develop tools and methodologies for BID.

3.2 METHODOLOGY FOR BID BENEFITS STUDY

Accounts of the benefits of BID from 128 different sources – 114 academic and 14 non-academic – were identified in BID literature and grouped. The accounts represent the work of 257 different authors, published in 17 journals, 4 conferences, 14 academic

26 books, and 14 non-academic sources. A list of all sources analyzed in this study is provided in Appendix E. Numerous other sources were also consulted, but were not directly included in the study. Sources were selected for use in the study when a claim or explanation of the benefits of BID was found, by chance, in the literature. Many sources come from the same special issue journals, conferences, and compilation books focused on BID. Different sources written by the same author were analyzed separately. Hence, large numbers of sources containing a particular claim likely indicate that the claim is widely held and/or is considered important by a small minority of prolific authors. Either case was deemed sufficient to justify examining the claim in further detail. Effort was made to ensure a broad search scope by including a wide range of academic publications and authors. However, no effort was made to select sources randomly or methodically. Consequently, claims that recur frequently in the study by a wide range of authors are likely to be pervasive in the field in general, but the ratio of the number of sources that make a particular claim to the total number of sources analyzed is unlikely to be numerically representative of the field.

3.3 RESULTS OVERVIEW

Quotations from the accounts were grouped according to meaning into 13 archetypal claims, organized into four groups, as shown in the figure below. These archetypal claims are the most generalized, confident versions of the claims authors make when referencing a particular benefit to BID. All of the other claims studied were either variations of these archetypal claims or particular instances of them.

Figure 8: Schematic depicting the 13 archetypal claims found and analyzed in this study.

There is substantial variation in the degree to which authors support the archetypal claim from which their claim is patterned; this variation is expressed through differences in the confidence and specificity levels of the claim-related quotations. The spectrum of affirmation of the archetypal claims is depicted in the figure below with examples seen in this study. On one end of the spectrum are highly-confident generalizations about biological systems or BIDs that indicate a high level of agreement with the archetypal claim in question; at the other are tentative examples of one possible

28 instance of the archetypal claim, indicating a low level of confidence in the archetypal claim. [70]. [71]. [72]. [73].

Figure 9: Spectrum depicting the varying extent to which authors affirm the archetypal claims found in BID literature study.

This variation indicates a rather large degree of disagreement or uncertainty in the BID field. What level of specificity is needed to accurately describe beneficial characteristics of biology and BID? How should generalizations regarding beneficial traits in biology and BID be qualified? The answers to these questions play a role in the development of tools and methodologies to improve engineered designs through BID. For instance, if it is true that ‘BIDs are always efficient’, new tools and methodologies are unnecessary, and standard

BID tools are sufficient to guarantee efficient designs. On the other hand, if (1) BIDs are only more likely to be energy efficient than a non-BID if they very closely imitate energy efficient mechanisms in biology, and (2) energy efficient mechanisms in biology are more likely to arise in situations where there is strong selection pressure on organisms for internal metabolic efficiency, then (3) tools and methodologies should be developed to hone in on biological analogies found in organisms with strong selection pressure for

29 internal metabolic efficiency and to assist in the direct transfer of the efficiency-related characteristics to engineering.

3.4 CONCLUSION

Chapter 3 presented an introduction to the BID benefits study, the methodology of the study, and an overview of the claims identified and analyzed. The 13 archetypal claims identified were grouped into four categories: those related to ideation, optimization in biology, sustainability in biology, and characteristics of BIDs themselves. Each of these categories will be analyzed separately in the four following chapters, where the archetypal claims will be unpacked, interpreted, and discussed using the support of textbooks and peer-reviewed research from biology and BID. As a result of this analysis, many of the claims are qualified and explained, providing insight into the development of future BID tools and methodologies.

30 Chapter 4: Ideation-Related Archetypal Claims

Five ideation-related archetypal claims are commonly referenced in the literature. These claims are shown in the mindmap in the figure below. One of the claims directly relates to the results of the BID ideation process; the other four concern characteristics of biology. Two of the biology-related traits – quantity and variety – are metrics commonly used to measure the results of ideation techniques; concept generation methods that result in a greater variety and number of ideas are considered superior to methods that produce similar or fewer ideas. It is not immediately clear, however, what advantage is conferred to the design process when the field of potential analogies is varied and numerous, instead of the pool of concepts generated. The other two biology-related traits concern the characteristics of biological systems that make them relevant to engineering design problems and may cause the results of BID to be different than the results of other design-by-analogy techniques. Each archetypal claim will be discussed in detail in this chapter.

Figure 10: Mindmap of ideation-related archetypal claims concerning benefits of BID.

4.1 BID HELPS DESIGNERS GENERATE NOVEL IDEAS.

26 sources out of 128 claim that novel, creative, innovative and/or new ideas result from bioinspired ideation. 14 sources refer directly to the ‘novelty’ of ideas, 5 to ‘new’ ideas, 4 to ‘creative’ ideas, and 10 to ‘innovative’ ideas, through statements such as: “[B]iology has created and continues to create effective solutions that offer great 31 models… as inspiration for novel engineering methods, processes, materials, algorithms, etc.” [69]; “[B]iology, bionics, and related fields offer rewarding new insights to designers” [74]; “[U]nique creative engineered solutions can be generated through functional analogy with nature” [67]; and “It is evident that nature can inspire innovative engineering designs” [75]. These claims are grouped and discussed together as the archetypal claim ‘Biological analogies help designers generate novel ideas,’ because each of the claims has related meanings to that effect and because the supporting evidence for these claims is the same. Many of these terms are considered synonymous in a broader, non-technical context, and an examination of the technical definitions of ‘new,’ ‘creative,’ and ‘innovative’ indicates that most sources consider these terms to be either equivalent to, or subsets of, ‘novel’ concepts. Although frequently the terms ‘novelty,’ ‘newness,’ ‘creativity,’ and ‘innovation’ are distinguished from each other within engineering design literature, generally-accepted technical definitions of a number of these terms remain

“elusive” [76]. Novelty is defined as “a measure of how unusual or unexpected an idea is as compared to other ideas” [77]. Innovative ideas are either regarded as a subset of creative ideas that are useful and feasible [78], or they are regarded as a subset of novel ideas

[76]. Similarly, creative ideas are either considered a subset of novel ideas that are valuable [79], or they are considered synonymous with novel ideas, because creative ideas are the ideas that are outcomes of creativity and creativity is “a process to evaluate a problem in an unexpected or unusual fashion in order to generate ideas that are novel” [78]. Finally, new ideas are either considered synonymous with novel ideas, or they form a broader category that is not necessarily associated with characteristics desirable for ideation: “Not every new idea is novel since it may be considered usual or expected to 32 some degree and this is only known after the idea is obtained and analysed” [77]. For the sake of simplicity, here it is assumed that claims related to new ideas are using the term ‘new’ as a synonym for ‘novel.’ If this were not the case, the only implication would be that claims related to new ideas would not represent an actual benefit to designers. Because of their similarities, novel, new, creative, and innovative ideas are all discussed under the more general umbrella term ‘novel.’ Upon inspection of the literature, it appears that the use of biological analogies in ideation does indeed help designers generate novel ideas. Wilson et al. [80] found that designers who used biological analogies in ideation had an increase in the novelty of their ideas compared to a control group. Additionally, design-by-analogy in general has been shown to increase the novelty of ideas. Design-by-analogy is a concept generation technique where designers are primed with visuals and/or text prior to ideation. BID is one example of a design-by-analogy approach. The primes used in design-by-analogy encourage designers to think differently and can help solve design problems. The benefits of design-by-analogy in ideation are well-studied and include the ability to generate “new relevant structures” [81], enhance creativity during concept generation [82], help designers develop concepts that are “high quality and novel” [83], and enhance “innovation” [84].

However, BID is just one of many types of design-by-analogy, meaning these novelty-related benefits are not unique to BID. In the conclusion of their 2010 paper, Vattam et al. [85] state that it is an “open question” how analogies from BID differ from other types of analogies. Virtually anything could be used as analogy by a designer, such as frequently-used patents and biological systems, but also many less-frequently discussed potential analogies from anthropology, geology, astronomy, art, and literature, meaning there is a broad range of potential design-by-analogy processes. While many of 33 these processes are discussed less frequently in design literature than BID, theory related to design-by-analogy approaches suggests that they would share some of the same ideation benefits as BID. Many of these less-commonly discussed design-by-analogy techniques are being used. For instance, a study from Casakin et al. [81] involved three architectural design problems where participants were shown “images from the architectural design domain… as well as images from remote domains… like art, engineering, nature and science.”

Additionally, there is a fair amount of discussion on design inspired by science fiction.

For instance, Vincent and Mann [86] describe science fiction as “a fertile source of ideas for both technology and TRIZ,” and a news article from NASA explains how the space elevator concept was “inspired partly by science fiction,” from sources such as Arthur C. Clark’s book Fountains of Paradise [87]. However, some design researchers argue that the use of biological analogies has two benefits in ideation above those of typical design-by-analogy approaches. First, some authors maintain that BID is less prone to design fixation than other design-by-analogy methods. “Design fixation refers to design conformity that results from exposing designers to example solutions” [80], resulting in a reduced variety of ideas. Design-by- analogy has been shown to have negative effects in ideation related to design fixation

[80,83]. Design fixation has also been shown to be a problem in BID: “[N]ovice designers tend to fixate on irrelevant aspects of biological information” [88]. Mak and Shu [89,90] have observed issues with fixation on elements of the biological analogy description and fixation on applying the biological strategies to develop a specific type of solution during BID. However, design fixation may be less of a problem in BID than in other design-by-analogy approaches. A study examining the effect of biological analogies on ideation conducted by Wilson et al. [80] found that participants who used biological 34 analogies and human-engineered analogies both had increases in the novelty of their ideas, but also that the decrease in variety of design ideas that occurs as a result of using an analogy from engineering did not occur with biological analogies. Hence, it appears that BID has the novelty benefits associated with design by analogy without some of the common drawbacks, such as reduced variety of ideas. However, further research is needed to confirm these results. Second, some authors argue that BID is more likely to produce novel ideas because biological analogies are more likely to be far-field analogies than alternatives.

Some authors, such as Wilson et al. [80], claim that biological analogies are likely to be far-field because biological organisms share few surface-level attributes with engineering designs. Numerous previous studies have indicated that far-field analogies – analogies that come from a domain substantially different from the target domain [91] – promote novelty [83] and creativity [92] in concepts generated. A number of authors have agreed [84,89-91,93,94]. However, this novelty comes with a price; new research from Fu et al.

[95] indicates that far-field analogies may be problematic because they are more difficult to transfer to engineering design, and that mid-field analogies actually result in the best concepts generated. Ultimately, using biological analogies during ideation improves the novelty of concepts generated compared to a control group. This represents a true advantage over standard ideation techniques, but not over other design-by-analogy approaches, for which these improvements in novelty are also expected. However, BID may be less prone to cause design fixation than patent-based design-by-analogy techniques, although more evidence is needed. Additionally, BID may be more likely to produce novel concepts than alternative methods of design-by-analogy because biological organisms share few surface-level attributes with engineering design problems, and consequently a reduced 35 incidence of design fixation. However, the lack of surface-level similarities also means it is more difficult for engineers to transfer the information from the biological analogy to the engineering domain.

4.2 QUANTITY: BIOLOGY CONTAINS MANY POTENTIAL ANALOGIES.

20 out of 128 sources claim there are many potential analogies in biology. Sixteen sources make general statements, such as: “The natural world offers a wealth of potential design solutions that can be applied to engineering problems” [96]; and “The natural world provides numerous cases for analogy and inspiration in engineering design” [97]. Additionally, four sources reference specific types of functions that are performed in many different ways by nature, such as the great number of “specialized sensing tasks” performed by biological sensors [98]. Having a large number of biological species may appear advantageous to BID researchers because larger numbers of potential analogies may make it more likely to find an analogy that is relevant to a particular engineering problem.

When examined using biological literature, it is clear that there are numerous potential analogies in biology; however, many of these designs are currently inaccessible to engineers. “As many as 30 million species of organisms may exist on Earth today” [99], but in 1988 only 1.5 million species had been discovered and studied by biologists [100]. This issue has been discussed by authors in BID. For instance, Gorb et al. [101] mention that only a few adhesive systems have been studied and modeled from the pool of one million insect species recently known to science. However, there are many elements of any particular species that could be used as potential analogies – surface textures, shape of body parts, behaviors, etc. Hence, while there are many species in

36 biology, few can actually be used by engineers. However, the ones that are accessible can be used in a wide range of ways by engineers. On the basis of sheer numbers of potential analogies alone, it is unclear what advantage BID has over other design-by-analogy techniques, patent searches in particular. According to data from the World Intellectual Property Organization [102], an agency of the United Nations, approximately 36 million patents applications were filed worldwide between 1985 and 2011, with 2.14 million filed in 2011 alone. A book published in 1988 states: “In the United States alone more than 4.7 million patents have been issued since 1790. If each of these patents is counted as an equivalent of an organic species, then the technological can be said to have a diversity three times greater than the organic” [100]. Ultimately, biology does indeed have a very large number of accessible potential analogies to be used in engineering, despite the fact that only a small percentage of existing species have been discovered and studied. However, more potential analogies can be found in engineering. Hence, the great number of potential analogies is a benefit of BID, but it is not an advantage over existing design-by-analogy techniques that use patents.

4.3 VARIETY: BIOLOGY IS DIVERSE.

18 of 128 sources appeal to the archetypal claim that ‘biology is diverse’, though statements such as: “Organisms have evolved an immense variety of shapes and structures” [103]; “Biological systems which share common structural or functional principles may come in a large number of variations that almost always exceeds what is seen in man-made devices by a large margin” [104]; “There is a great diversity in properties and structures across hard biological materials, from which engineers can ‘tap’

37 for inspiration” [105]; and “With… seemingly simple molecules, natural processes are capable of fashioning an enormously diverse range of fabrication units” [106]. Diversity in biology is a potential benefit to practitioners of BID if it means that designers will be more likely to find an analogy relevant to their design problem. Additionally, if it appears that solutions in biology are more diverse than those in engineering, there may be an advantage to using biological analogies in those cases instead of engineered designs because the likelihood of finding a relevant analogy is higher.

Upon inspection of biological and BID literature, it indeed appears that biology is diverse. Biological organisms have an enormously broad range of traits and are able to live in nearly every environment on earth. For instance, a wide range of bacteria and microscopic plants and animals live in Antarctic sea ice [107], in environments as hot as 113°C [108], and in extreme chemical environments, such as those “contaminated with toxic metal ions” [109]. Biological diversity arose, in part, as a result of species adapting to a wide range of different environments. For instance, the evolution of vascular plants over the past 430 million years “in dramatically different environments over that time resulted in the formation of an impressive variety of forms and attributes, in a global diversity that today consists of approximately 260,000 species” [110].

It is unclear, however, whether biology or engineering is more diverse. Vincent and Mann [86] have observed qualitatively that biological solutions for the problem of joining two elements are “much more varied” than engineering solutions. However,

Basalla [100] claims that the same level of diversity is also present in engineering solutions: “The variety of made things is every bit as astonishing as that of living things. Consider the range that extends from stone tools to microchips, from water wheels to spacecraft, from thumbtacks to skyscrapers” [100]. 38 Ultimately, it appears that there is indeed a great deal of diversity in biology, meaning many different types of analogies may be found to improve engineering designs, and the likelihood of finding a relevant biological analogy for a particular problem is high. However, it is unclear whether there is greater diversity in biology or engineering and, hence, whether one is more likely to find a relevant analogy to a particular problem in the population of accessible biological analogies or in the population of patents.

4.4 RELEVANCE: BIOLOGY SOLVES PROBLEMS ENGINEERS WOULD LIKE TO SOLVE.

At least 44 of 128 sources appeal to the archetypal claim that ‘biological systems solve problems engineers would like to solve’ through statements such as: “[T]hrough biological and biochemical systems, many of the same problems mankind faces have been met and solved” in nature [74]; and “Natural systems often solve problems in adequate, not optimal or maximal ways. However, even ‘adequate’ designs can be an important and revolutionary source of inspiration for problems we are trying to solve” [111]. Authors likewise admire a wide range of biological phenomena engineers have yet to imitate, including “the low friction coefficients in many natural systems” [112]; “how basilisk lizards walk on water … how penguins minimize drag… and how insects manage to remain airborne” [113]; the adaptability, multifunctionality, and scalability of biological materials, as well as “their unique combinations of stiffness and strength” [105]; and “hydrophobicity, wind resistance, self-assembly, and harnessing solar energy” [9], among many other features. This archetypal claim may be one of the most oft-cited reasons for conducting

BID. At the beginning of this study, this claim was not recognized as being of interest and instances of this claim were not always recorded. Hence, there are likely more than 44 quotes to this effect in the 128 sources studied.

39 The claim ‘Biology solves problems engineers would like to solve’ indeed appears to hold true. The first part of this claim ‘Biology solves problems’ is essentially the same as the claims ‘Biology works’ or ‘Biology performs functions’. It is clear that biology does indeed successfully perform a vast array of functions. The overall archetypal claim – that the solutions found in biology are of interest to engineers – is also likely true, since the authors making this statement are frequently also practitioners of BID. Through their existence, biological systems prove to engineers that it is possible to perform a particular function and provide an example of a mechanism or problem-solving approach that works. Of course, the process by which one learns from biological examples to create a design in engineering is not without difficulty; authors discuss challenges faced by engineers because of their limited knowledge of biology [94,114], the need for a more systematic method of BID [115], and difficulties arising from “copying nature” as opposed to “using nature as inspiration” by using “its principles to invent far more effective solutions” [69]. Ultimately it appears that biology does indeed solve a vast array of design problems and that the design solutions found in biology are of interest to engineers, despite the challenges engineers may face in trying to implement similar solutions in engineering designs.

4.5 BIOLOGY SOLVES PROBLEMS DIFFERENTLY THAN ENGINEERING.

Seven out of 128 sources claim that biological systems solve problems differently than engineering. Five sources make general statements, such as: “nature copes and invents in a way fundamentally different from what we do” [116]; “evolution produced sophisticated properties and structures which rarely overlap with methods and products made by

40 man” [117]; “when performing the same task as an organism, humans can often use very different strategies, for example, aerofoil wings versus flapping wings to achieve flying” [118]. Additionally, five sources give specific examples of differences between engineering and biological solutions, such as: “We build dry and stiff structures; nature mostly makes hers wet and flexible… Our engines expand or spin; hers contract or slide. We fabricate large devices directly; nature’s large things are cunning proliferations of tiny components” [116].

A limited amount of BID literature supports the claim that solutions in biology and engineering are fundamentally different. For example, a study from Vincent et al. [11] comparing the principles illustrated by problem solutions in biology and engineering, found, using analysis from TRIZ, that there is only a 12% overlap in these principles and that biological systems are more likely to solve problems using information- and structure-based solutions, whereas problems encountered in technology are typically solved though energy manipulation. Additionally, Vincent [71] generated a plot showing the differences in the solutions found in biology and engineering at different length scales, reproduced below. As can be seen from the visual differences in the two charts in Figure 11, there appears to be a significant difference in the manner in which problems are solved in biology and engineering.

Figure 11: “How problems are solved in (a) technology and in (b) biology, showing all possible problems (vertical axis) and size range (horizontal axis). While 70% of the technical solutions involve manipulation of energy (amount, source, type, etc.), the use and manipulation of information, from DNA to pheromones is most important in biology” [71].

Of course, some sources appear to disagree with the claim that biology and engineering have fundamentally different types of solutions, emphasizing instead the similarities between biology and engineering. For instance, Nagel et al. state: “Biological organisms operate in much the same way that engineered systems operate; each part or piece in the overall system has an intended function. Function thus provides a common ground” [119]. However, there is little, if any, evidence in biological and BID literature

42 refuting the empirical differences uncovered in the studies by Vincent and Vincent et al., discussed above. If biological mechanisms truly differ fundamentally from those in engineering, using biological analogies in ideation would give different results than ideation using results from a patent search, potentially offering an advantage over just using analogies found from patent search, or possibly even an advantage over patent-based analogies. Currently, there is some authoritative literature from the BID community supporting the claim that biology and engineering are fundamentally different, as discussed above, but further work is needed to confirm these results and to see if this does indeed result in further advantages for the BID process.

4.6 CONCLUSION

BID does indeed help designers generate novel ideas. There is significant evidence indicating that using biological analogies in concept generation produces more novel concepts than standard concept generation techniques. However, the same is true for other design-by-analogy techniques, such as those that use patents as analogies. Some evidence suggests that biological analogies may be less likely to prompt design fixation than patents, but they may also be more difficult to understand and translate to a new engineering design than information in patents. It is also the case that biology contains many potential analogies. Ultimately, biology does indeed have a very large number of accessible potential analogies to be used in engineering, despite the fact that only a small percentage of existing species have been discovered and studied. However, more potential analogies can be found in engineering patents. Hence, the great number of potential analogies is a benefit of BID, but it is not an advantage over existing design-by-analogy techniques using patents.

43 Additionally, according to the engineers who make this claim, biology contains solutions relevant to the problems engineers want to solve. Ultimately, it appears that there is indeed a great deal of diversity in biology, meaning many different types of analogies may be found to improve engineering designs, and the likelihood of finding a relevant biological analogy for a particular problem is high. However, it is unclear whether there is greater diversity in biology or engineering and, hence, whether one is more likely to find a relevant analogy to a particular problem in the population of accessible biological analogies or in the population of patents.

Some preliminary evidence exists suggesting biological mechanisms differ fundamentally from those in engineering. If true, this may represent an advantage of BID over only using analogies found from patent search, or possibly even an advantage over patent-based analogies. However, further work is needed to confirm these results and to see if this does indeed result in advantages for BID.

44 Chapter 5: Optimization in Biology

38 sources reference the claim ‘Biology is optimized’ through statements such as: “Nature solves complex real-world problems by maximizing fitness via natural selection. We see the end product of this optimization in biological structure and function” [120]; “Evolution and natural selection has led to optimized and highly robust biological systems” [62]; and “Generation of design in natural systems (geometry, pattern, form, and texture) is a holistic phenomenon that synchronizes all design constituents toward an overall optimized performance envelope” [121]. These sources also provide specific examples of optimized biological systems, such as the magnetic properties in magnetotactic bacteria [122], the nozzle diameter in the ‘combustion chamber’ for the bombardier beetle [123], and the morphology of flying animals [124]. Quotations from accounts that referenced ‘optimization in biology’ were grouped into three archetypal claims: (1) Biology is optimal; (2) Biology is optimized by evolution via natural selection; and (3) Biology is optimized for efficiency – 21 sources.

Claims 1 and 2 are two different possible interpretations of statements related to ‘optimization in biology’ in general and are not associated with a corresponding quotation count because it is often ambiguous which interpretation is best aligned with the authors’ intent. These claims are depicted in the figure below.

Figure 12: Mindmap of optimization-related archetypal claims.

45 Additionally, a set of concepts related to optimization in biology were frequently referenced: (1) Evolution – 37 sources, (2) Natural selection – 9 sources, (3) Evolution as research and development – 3 sources, (4) Evolution as experimentation – 6 sources, (5) Evolution as trial and error – 5 sources, (6) Evolution has been occurring longer than engineers have been developing products – 4 sources, (7) Niches – 6 sources, (8) Evolution over millions of years – 15 sources, (9) Evolution over billions of years – 25 sources, (10) ‘Fossils are failures’ – 8 sources, and (11) Biology is adaptable – 8 sources.

5.1 BIOLOGY IS OPTIMAL.

References to optimization in biology may mean ‘biology is optimal’ or ‘organisms are perfectly suited to their environment.’ The following quotations seem to refer to optimization in biology in this sense: Biological “structures have evolved in nature over eons to the level of seamless integration and perfection with which they serve their functions” [125]; “The highly specific control of morphology, location, orientation and crystallographic phase all indicate the existence of an optimized or ‘engineered’ substrate surface” [126]; and “The numerical simulations show that the nozzle diameter in bombardier beetles appears to be at an optimum value” [123]. However, a number of sources in BID literature disagree. Bar-Cohen [69,127] claims organisms do not necessarily exhibit optimal performance because they only need to survive long enough to reproduce. Likewise, Ball [68] describes nature as “lean and, in some sense, optimal” but makes it clear that biological organisms are not optimized from an engineering perspective: “The complex of compromises that shape the fitness landscape of evolution is likely to bear only incidental correspondences to that which determines the contours of technological and economic viability.”

46 Upon inspection, it is evident that biological organisms are not perfect or ‘optimal’ for four reasons. First, biological organisms are not ‘optimal’ because many organisms have vestigial structures that have lost all or most of their historical function. “Vestigialization begins when a trait is rendered nonfunctional, or becomes a selective liability outright, due to shifts in the environment. The feature then atrophies over time” [128]. Examples of vestigial structures include “simplified morphology of parasitic animals, reduced number of digits in horses, loss of limbs in snakes, the vermiform appendix and coccyx of humans, vestigial wings of flightless birds, eye and pigment loss of cave-dwelling organisms” [128] and the hindlimbs in the ancient whale Basilosaurus [129]. Optimal organisms would not possess functionless features. Second, biology is not ‘optimal’ because mutations have not arisen to produce all possible phenotypes, including those that would be extraordinarily beneficial. It is apparent from studies of species morphology “that forms generated during evolution fall into distinct, not continuous, classes” [130]. Consequently, traits that would increase fitness may not be present, and it is not always possible for the evolutionary process to arrive at the optimal solution. For example, “In the seedcracker, bills of a particular size have a genetic basis. In experimental crosses between two birds with the two optimal bill sizes, all offspring had a bill of one size or the other, nothing in between” [131]. If a mid- size bill were optimal in some environment, the seedcracker as it currently is would not be able to evolve to be optimal because the genes to produce the optimal phenotype are not possible. An optimal organism would have the best of all possible features, which existing organisms do not have. Third, biology is not ‘optimal’ because not all combinations of traits are possible, including desirable ones. In some cases, this is because some traits share development 47 pathways that cause them to be inherited together [132]. For instance, “[i]n several species of poeciliid fish… the process of maturation is governed by an endocrine pathway that reduces growth rate as it accelerates sexual development,” meaning “the genetic variation for the combination of large size and rapid maturation is not immediately available” [132]. In other cases, not all combinations of traits are possible because of the physical realities of the existing organism. For instance, in a section titled “Why Natural Selection Cannot Fashion Perfect Organisms” Campbell and Reece state:

“[N]ature abounds with organisms that seem to be less than ideally ‘engineered’ for their lifestyles”; they provide the example of bird species that might benefit from having four legs instead of just two, which is not possible because the two limbs evolved to be wings, leaving only two limbs to remain as legs [133]. An optimal organism would have the best of all possible combinations of features, which existing organisms do not have. Finally, biology is not ‘optimal’ because the environment is constantly changing, making it impossible for biological organisms to be perfectly suited for their environment at all times. Unlike an engineering optimization problem with a fixed set of constraints and a fixed global optimum, the environment in the biological world is constantly changing. Consequently, what qualifies as ‘the optimum’ in biology is a “moving target” [134], and ‘the fittest’ individuals are “those best adapted to existing conditions at a particular historical moment in a specific environmental context” [135]. Hence, while natural selection processes may ‘optimize’ biology, as discussed in the following section, and favor a particular trait at one point in time, it can later ‘optimize’ and disfavor that same trait in the same population, solely in response to changing environmental conditions. Accordingly, if the evolutionary process is one of optimization, there is no fixed goal to the process, and hence there is no single global optimum to approach. If the environment were unchanging over many generations, perhaps organisms would begin to 48 approach the ‘optimum’ associated with that environment, but this type of optimization is not possible in a changing environment. An ‘optimal’ organism should be optimal for all time, not just ‘optimal’ today and ‘non-optimal’ tomorrow; this is not possible in a changing environment. Despite some examples of well-adapted organisms cited in the literature, biological organisms are not optimal, or perfectly adapted to their environments, because many have features that evolved historically but no longer serve a purpose, while others lack traits or combinations of traits that would be beneficial. Additionally, the environment is constantly changing, making it impossible for biological organisms to be perfectly suited for their environment at all times.

5.2 BIOLOGY IS OPTIMIZED BY EVOLUTION VIA NATURAL SELECTION.

Alternatively, references to ‘biology is optimized’ can also mean ‘biology is subject to an optimization process.’ This appears to be the meaning in the following quotations: “Nature solves complex real-world problems by maximizing fitness via natural selection. We see the end product of this optimization in biological structure and function” [120]; biological “approaches have been tested and improved upon for millions of years; they are continuously being optimized with respect to their function and environment” [112]; and “flyers in nature have been subjected to strong selection for optimum morphology” [124]. Authors in the BID community generally agree that the only optimization process in biology is evolution or, more specifically, evolution via natural selection. 37 out of 128 sources directly reference ‘evolution,’ and 9 reference ‘natural selection’ in their account of BID; no sources consulted suggest that biology is optimized by another process. While ‘evolution’ does not imply optimization – “evolution simply means heritable change in a

49 line of descent” [131] – natural selection is associated with optimization and adaptation [133].

5.2.1 Metaphors for ‘Evolution’ in BID Literature

BID authors commonly use three metaphors for evolution via natural selection: ‘research and development’ (R&D) – 3 sources; ‘experimentation’ – 6 sources; and ‘trial and error’ – 5 sources. They liken these three concepts to evolution through statements such as: “After 3.8 billion years of research and development, failures are fossils, and what surrounds us is the secret to survival.” [21]; “After billions of years of trial and error experiments, which turn failures to fossils, nature has created an enormous pool of effective solutions” [69]; and “Through the course of 3.8 billion years, nature has gone through a process of trial and error to refine the living organisms, process, and materials on planet Earth” [9]. Upon inspection, it does not appear that R&D and experimentation are apt metaphors for evolution. Ball [68] appropriately remarks:

It would be foolish to assume that natural selection stands proxy for the testing laboratory or the market, refining a design in just those ways that a new product demands. The complex of compromises that shape the fitness landscape of evolution is likely to bear only incidental correspondences with that which determines the contours of technological and economic viability.

When examined more closely, it is evident that there are substantial and fundamental differences between the conscious, intentional, goal-oriented processes of R&D and experimentation and the mechanistic, agent-less, goal-less process of evolution.

These inaccurate metaphors for the evolutionary process prove problematic and cause authors to draw false conclusions. For instance, four sources claim that biological analogies are useful because ‘biology has been evolving much longer than humans have been researching solutions to similar problems.’ Richter and Grunwald [136] claim: 50 “Nature has been developing adhesives for millions of years, mankind for just a few thousand years. For this reason it is worth having a closer look at what nature does and how we can develop bio-inspired adhesives for technical and medical applications.” Ball [68] also states: “[S]everal thousand good engineering heads cannot compete with the billions of years that evolution has had to experiment, select and refine.” If evolution were comparable to R&D or experimentation in an engineering context, this argument makes sense: certainly 3.8 billion years of R&D should have resulted in fabulous designs, compared to the few hundred thousand years of R&D that could have been undertaken since the dawn of humanity. Unfortunately, of course, the process by which organisms evolve in nature and the process by which products are developed are in no way equivalent and, in fact, are totally and fundamentally different, so the argument does not hold. Evolution via natural selection does not optimize biological organisms the same way (or at the same speed) engineers optimize products through R&D or experimentation.

To distance themselves from the notion that evolution is an intentional process, five authors instead use the metaphor of ‘trial and error’ for evolution. Yen et al. [137] pointedly choose this metaphor “to make plain that differences between intentional design to produce a desired function and the unintentional, trial-and-error process of evolution.” The notion that evolution is trial and error could be appropriate if one sees ‘errors’ as mutations or traits that prove disadvantageous to a particular organism in a specific time period and environment.

In all cases, however, these metaphors for evolution lack the scientific detail necessary to clearly define the ways in which the evolutionary process does and does not optimize biology. Hence, a detailed discussion of evolution via natural selection is necessary. 51 5.2.2 Evolution via natural selection optimizes populations.

Evolution via natural selection ‘optimizes’ or ‘adapts’ populations to their environments. Through natural selection, the fittest individuals in a population, those best suited for their environment, are most likely to survive and reproduce, causing traits that confer higher fitness to become more common. Natural selection adapts populations to particular ecological niches. “The general idea of ‘niche’ refers to the ecological conditions that a species requires to maintain populations in a given region, together with the impacts that the species has on its resources, other interacting species, habitat, and environment” [138]. Ecological niches are characterized by the dynamic effects between resources and consumers – by both the “environmental factors” that “allow a species to exist in a given geographic region or in a given biotic community” and the “effects… the species” has “on those environmental factors” [138]. Different ecological niches place different demands on the same species, meaning that the fittest set of traits for a particular species likely differ between populations in different niches that face different environmental challenges. Six sources reference ‘niches’ in their accounts of BID. Additionally, populations become ‘optimized for’ or ‘adapted to’ their ecological niches via natural selection operating on the relative fitness of different organisms within the population. This means that the fitness of an organism as a whole – with the effects of all traits and combinations of traits – is optimized, not the engineering-related performance characteristics of traits of interest to engineers.

A wide range of authors agree that the fitness of an organism as a whole is selected for, not the beneficial features of a particular trait. Gunderson and Schiavone [139] state that it is the way an organism as a whole operates – not any one particular system within the organism – that makes it successful. Ball [68] suggests it may not be 52 possible or practical to try to isolate a desirable biological feature from the organism that possesses it. Campbell and Reece [133] discuss adaptations as compromises between conflicting needs and show that biological organisms face multiple conflicting objectives; for instance, humans’ prehensile hands and flexible limbs allow us to be more agile and athletic, but also open us to the threat of ligament injury. These compromises between conflicting needs can be observed through the many types of natural selection that operate in biology – including gene selection, kin selection, frequency-dependent selection, and sexual selection – which proceed via different mechanisms and affect populations in different ways. In some cases, features favored by one selection process prove disadvantageous in another process. For instance, the bright plumage found in male peacocks is selected for through intersexual selection, but it is costly [140] because it may increase the risk of being eaten by predators and consumes a significant amount of energy to produce and carry [141]. Additionally, Schluter et al. [142] discuss opposing selection, where fitness is both enhanced and reduced by the same trait at different life history stages. One example of opposing selection occurs in the medium ground finch where “survival selection favors small size in young birds but large size in adults” [143]. Since evolution via natural selection is a multi-objective optimization process, where many conflicting needs of an organism are optimized together, an ‘optimized’ kingfisher, for instance, would not have an optimized beak shape, but would instead have all its features – its organ function, reproduction, behavior, and its beak shape, among millions of other traits – optimized collectively. Some of these traits have little relevance to engineering parameters. For instance, features that arise via intersexual selection to make an individual more appealing to members of the opposite sex are unlikely to be relevant to engineering. 53 Engineers frequently fail to recognize that optimization in biology has multiple objectives, and they are unlikely to think about the factors being optimized besides the engineering parameter of interest to them. For instance, Helms et al. [144] observed that a common error undergraduates make when conducting BID is to oversimplify optimization problems: “For example, designers viewed the structure of moss as a surface area optimization problem for gathering sunlight, while ignoring protection and water preservation requirements of the plant.”

Hence, evolution via natural selection optimizes populations in the sense that it causes populations to become better adapted to their unique environmental conditions. This process optimizes the fitness of organisms as a whole, including many different objectives related to survival and reproduction, which are reflected in the many types of selection pressures populations experience. Consequently, individual traits are unlikely to be optimized for engineering parameters.

5.2.3 Factors that Impede Optimization via Natural Selection

However, evolution involves a number of factors that steer populations away from ‘optimized’ fitness by natural selection. Lynch [145] draws attention to the existence of these non-adaptive forces in biology:

The vast majority of biologists engaged in evolutionary studies interpret virtually every aspect of biodiversity in adaptive terms. This narrow view of evolution has become untenable in light of recent observations from genomic sequencing and population-genetic theory.

Many of the same factors make it challenging to positively identify optimization of a population via natural selection when and if it is occurring because they cause non- beneficial alleles to rise in prevalence. Hence, one cannot claim that a trait is becoming ‘optimized’ in a population simply because the alleles are becoming increasingly

54 prevalent. Below, genetic drift, gene flow, and mutations – particularly the mechanisms of biased mutation, gene conversion, genetic hitchhiking, and large mutations – will be discussed in this context of countering optimization by natural selection and/or making it more difficult to identify true adaptations when they occur. Genetic drift both counters natural selection and makes it more difficult to identify true adaptive evolution. Genetic drift is a process whereby the frequencies of genetic variants fluctuate randomly over generations, “sometimes causing an initially rare variant to become established (fixed) in a species” [146]. Genetic drift can ultimately counter optimization via natural selection: “[B]y magnifying the role of chance, genetic drift indirectly imposes directionality on evolution by encouraging the fixation of mildly deleterious mutations and discouraging the promotion of beneficial mutations” [145]. It can also “overwhelm selection” under conditions where the effective population size is low and selection is sufficiently weak [147]. Because of genetic drift, the observation that a particular trait has become prevalent in a population does not necessarily mean that the population is becoming optimized for this trait; it may just be a result of random factors. This is especially true in small populations, where genetic drift has the largest effect. Gene flow describes the flow of genes between otherwise separated populations through mating. Consequently, gene flow “helps keep separated populations genetically similar” [131], meaning it counteracts any sort of ‘optimization’ arising via natural selection to make either population better suited for its unique environmental conditions. While mutations introduce the genetic diversity that enables natural selection to optimize traits, they also typically lead populations away from the ‘optimum’ introduced via natural selection. Mutations typically have a negative effect on organisms; “a single mutational change is about as likely to improve the genome as blindly firing a gunshot through the hood of a car is likely to improve engine performance” [133]. If a population 55 were, at some point, composed of only individuals possessing the global optimum of a particular trait, mutations in the offspring of this optimized population would appear, de- optimizing the population. “[G]enome composition is governed by biases in mutation and gene conversion” [145], meaning biases in mutation and gene conversion can have a significant effect on the traits arising within a population. Biased mutations can change the direction of evolution, not because that direction of change is better than any other, but because there are more likely to be mutations – and hence, more likely to be favorable mutations – in that direction. Stoltzfus and Yampolsky [148] explain how mutation bias is a source of nonrandomness in evolution, imposing “predictable biases on evolution.” Biased gene conversion can have a similar effect; “[b]iased gene conversion is a process by which a heterozygote is converted into a homozygote during recombination; this is often biased in favour of one of the two alleles, resulting in one allele being driven through the population” [149]. In both biased mutation and gene conversion, alleles are become more prevalent in a population as a result of chemical or molecular properties of the genome itself. Genetic hitchhiking can cause unfavorable traits to become fixed in a population because these traits are associated with other, more favorable, mutations. Genetic hitchhiking occurs when a “favourable mutation arises, and increases to fixation,” giving “a fortuitous advantage to all the genes with which it was originally associated” [150]. In some cases, the associated genes can also become fixated in the population. Larger populations are more likely to experience beneficial mutations and are consequently also more likely to experience the effects of genetic hitchhiking [151]. “[T]he level of recombination… influences the sensitivity of a locus to spurious hitch-hiking effects” [145]. 56 In addition, large and otherwise beneficial mutations leading to ‘optimization’ of a population from an engineering perspective frequently cannot remain in the population due to biological constraints. Organisms with mutations that result in a drastic change in the organism often prove lethal or prevent the organism from reproducing [131]. BID authors, Knippers et al. [152] make reference to this point when they note that the structures organisms have inherited “and the fact that living beings have to ‘function’ successfully during all phases of evolution confine the potential of natural selection as an optimizing agent.” Additionally, Vincent [86] states that biological organisms are unlikely to be able to find global optima via the evolutionary process, except in cases where environmental factors force temporary de-optimization of organisms away from a local optimum. This is because mutations that cause major phenotypic differences from the local optimum are unlikely to survive and reproduce, and small mutations that cause slight phenotypic differences from the local optima are likely to prove inferior to the local optima, making them less likely to remain in the population.

Accordingly, evolution via natural selection is an optimization process in the sense that when selection pressures dominate the other factors that affect evolution – the rate of gene flow and mutation – a population should be becoming increasingly better suited to its environment with each successive generation. However, if there is not strong selection pressure for a particular trait, or if the rates of the other factors are high, this will not be the case. Likewise, biological realities dictate that large mutations, which might otherwise be beneficial from an engineering perspective, are rarely viable, impeding biology’s optimization from an engineering perspective.

57 5.2.4 Macroevolution: Speciation and Extinction in the Context of Optimization

To this point in the chapter, evolution via natural selection has been discussed only in the context of “adaptive modifications within populations over time,” or microevolution [153]. Microevolution is presumably what most BID authors have in mind when discussing optimization in biology when they mention features that evolved in biology with enviable performance characteristics or ‘evolution over millions of years.’ 15 sources mention ‘evolution over millions of years’ in their accounts of BID.

However, a subset of BID authors appear to refer to macroevolution, which involves “speciation and the origin of the divisions of the taxonomic hierarchy above the species level” [153] and occurs on geologic time scales. Presumably, the 25 BID accounts discussing the “3.8 billion years of evolution” [21] and “evolution by natural selection over the past few billion years” [116] refer to macroevolution. Authors also likely discuss macroevolution when they make statements such as “failures are fossils” [21] and “the experiment in the evolution of mega-scale terrestrial biology failed… [it] ended with the extinction the prehistoric mega-creatures (e.g. dinosaurs and mammoths)” [69]. Eight sources contain quotations to this effect that state or imply that extinct species are “failures” [21,69], “unsustainable” [28,154], unsuccessful [24,155], poorly adapted [156], and not adaptable to other environments [154]. The types of characteristics that would evolve via natural selection acting over billions of years are likely related to the ability of organisms to survive environmental change and adapt quickly to new environments. 8 BID sources reference ‘adaptability in biology,’ possibly referring to the evolution of an enhanced ability to adapt to different environments. An organism’s ability to adapt involves how robust it is to different environments, how phenotypically plastic it is, and the rates of mutation experienced by

58 the organism. Each of these characteristics and the likelihood that it could arise via natural selection will be discussed in detail below. First, it is possible that natural selection over 3.8 billion years would select for hearty organisms, capable of living as-is in a wide range of environments. Indeed, work from Payne and Finnegan [157] shows that “geographic range is likely the most consistently significant predictor of extinction risk in the marine fossil record” for the Phanerozoic era, with a wide geographic range “significantly and positively associated with survivorship.” If organisms live over a broad geographic range they are likely to have the ability to survive in many different environmental conditions, meaning that many types of small environmental changes are unlikely to devastate their populations, as they are already environmentally flexible. Additionally, a wide geographic range makes it more likely that localized environmental changes that might prompt the death of all affected members of the species are less likely to cause the extinction of the species, because it reduces the chance that all members of a species will be affected.

Second, evolution over billions of years could have selected for phenotypically plastic organisms, those that have genotypes that are able to change phenotype as a result of environmental conditions. In some sense, selection for phenotypic plasticity could be considered the optimization of “the way in which an individual responds to environmental influences” [158]. Agrawal [159] maintains that “[t]he evolution of adaptive phenotypic plasticity has led to the success of organisms in novel habitats, and… phenotypic responses in species interactions represent modifications that can lead to… expanded evolutionary potential of species.” However, there is disagreement in the field regarding the overall effect of phenotypic plasticity and “its role in adaptive evolution” [158].

59 Third, evolution via natural selection over billions of years may select for blood lines capable of mutating rapidly to meet changing environmental conditions. For instance, “Galápagos finches can evolve a 10% change in average body size or bill size in a population in a single year in response to either droughts or heavy rainfall” [132]. The evolvability of a biological organism is related to how easily “natural selection directly advanc[es] features of genomic architecture, genetic networks, and developmental pathways to promote the future ability of a species to adaptively evolve” [145]. One component of evolvability could be selection for mutation rate, with populations with high rates of viable mutations more likely to survive environmental change. Hodgkinson and Eyre-Walker [149] explain the factors that contribute to whether there will be selection for the mutation rate – effective population size, current mutation rate, the degree to which the mutation rate changes, “the number of affected sites and the average effect of a mutation.” They show that there does not appear to be selection on the mutation rate in humans and that “[T]he evidence that some genomic regions have been selected for high or low mutation rates is weak” [149]. Additionally, the existence of evolvability is controversial, and some authors, including Lynch [145], argue that it is a myth. Regardless of the doubts regarding the existence of optimization via macroevolution, even if this type of optimization does exist, it is unlikely to be applicable directly to engineering design. Engineers might be able to learn from biology how to develop mechanisms that can operate in many different types of terrain or different temperature ranges, as the ‘robust’ or ‘hearty’ organisms do. However, while it would be wonderful if engineers could also learn how to make functionally plastic designs or more evolvable designs from biology, the reality is that biology’s mechanism for doing this – genetic mechanisms operating over many generations – is not relevant to mechanical 60 engineering design. As the human-engineered designs of interest here are not made of DNA and do not reproduce, the mechanisms of genetics to generate adaptable designs are not relevant. ‘Fossils are failures’ may hold true in the sense that extinct organisms may not have been sufficiently robust, sufficiently phenotypically plastic, or had sufficiently-high mutation rates for any of their descendents to survive in a changed environment. However, upon inspection it does not seem appropriate to think of all, or any, extinct species as ‘errors’ or ‘failures’ from an engineering perspective. First, many reasons unrelated to biological fitness may cause a species to go extinct. For instance, Bar-Cohen [69] notes:

[T]he extinction of a species is not necessarily the result of a failed solution; it can be the result of outside influences, such as significant changes in climate, the impact of asteroids, volcanic activity, and other conditions that seriously affect the ability of specific creatures to survive.

Reznick and Ricklefs [153] provide similar reasons as the cause of mass extinctions:

“Mass extinctions have external causes, including bolide (large crater-forming projectile) impacts, major tectonic events, and climate change.” One can hardly call a species that goes extinct as a result of an unlucky proximity to an asteroid impact or volcanic activity an ‘error’ on the part of biology. From an engineering perspective, it seems that any physical system that was once viable in biology has potential to be of interest to engineers. There is no reason to think that the beak profile of the kingfisher has anything more to give engineering than the beak profile of a pterosaur, for instance, simply by virtue of the fact that kingfishers are alive today. Hence, it does not appear that optimization through macroevolution via natural selection has direct applications in engineering design the way the microevolution via natural selection does.

61 On the scale of billions of years, macroevolution via natural selection may occur, optimizing populations to produce hearty organisms capable of surviving in many different environments, phenotypically plastic organisms, or organisms that are highly evolvable and have high rates of positive mutations. However, these types of optimization frequently prove controversial in biological literature. Additionally, it is unclear how optimization for these favorable genetic processes could be applied to engineering design.

5.3 BIOLOGY IS OPTIMIZED FOR EFFICIENCY.

21 sources refer to the archetypal claim ‘Biology is optimized for efficiency’, through statements such as: “Biomimicry refers to the process of using nature’s efficient design solutions to inspire engineering innovations” [62]; “The evolution of nature led to the introduction of highly effective and power efficient biological mechanisms” [69]; “Biological materials are produced by self-assembly… in a way that costs minimal energy” [155]; and “during ~ 3.4 billion years of fierce evolutionary competition nature has refined energy conversion efficiency” [24]. Because biological organisms have many characteristics that are optimized together, as discussed above, it is unlikely any specific energy- or materials-related characteristic is optimized for efficiency from an engineering standpoint. Hambourger [70] makes a similar point: “[T]hroughout evolutionary history, nature has always selected the most reproductively fit individuals, not necessarily those with the attributes most readily adapted to fulfilling human energy needs.”

Efficiency is, however, one of many factors potentially being selected for in natural selection: “As fitness-related traits are often energetically costly, selection should also act directly on the energetics of individuals” [160]. A number of authors claim that

62 selection pressure related to energy consumption is present, along with other important factors, for specific biological systems. For instance, Sengupta et al. [161] “argue that natural selection for energy-efficiency could help explain both the shape of the action potential and the underlying biophysics of ionic currents” in mammalian brains. Fong et al. [128] discuss eye and pigment reduction in cave animals as being the result of “energy economy in resource-poor environments” and the “flightlessness in some island-dwelling birds” as occurring as a result of a drive toward metabolic efficiency. Niven and Laughlin

[162] discuss the tradeoffs between the fitness benefits associated with sensory information and the energetic costs associated with sensory-related muscle- and neural- energy consumption. Ruxton and Wilkinson [163] maintain that sauropod dinosaurs would have benefitted energetically from the elongation of their necks, allowing them to access higher and lower foliage without needing to move their large bodies, but that these energetic benefits would have been countered by other factors, such as “mechanical aspects of the support and control of a long structure – or breathing considerations” that would have countered the energetic benefits at some optimum neck length. However, efficiency is not always an important factor in selection, and sometimes organisms actually have a higher fitness because they are inefficient. For example, Barber [164] maintains that on a global scale, there is low selection pressure promoting energy efficiency in photosynthesis because the raw materials needed for photosynthesis, including sunlight, “are available in almost unlimited amounts,” and as a result, photosynthetic efficiencies are low, rarely exceeding 1 or 2%. Additionally, Boratynski et al. [160] found that for female bank voles, internal energy efficiency – or a low metabolic rate – actually reduces fitness levels and increases the likelihood that the voles will die during the long Finnish winter.

63 Consequently, when analyzed on a case-by-case basis, it quickly becomes apparent that no generalization can easily be made regarding the selection pressure that energy consumption applies to organisms. Many organisms are optimized by natural selection to be efficient, while others are selected to be inefficient.

5.4 CONCLUSION

Although many examples of well-adapted biological organisms exist, organisms are not perfectly adapted or ‘optimal’ for their environments. Organisms frequently have features that serve no purpose, and they lack features and combinations of features that would be highly beneficial to them. Also, since the environment is constantly changing, it is not possible for organisms to be perfectly adapted to their environments at all times. All biological organisms are subject to evolution via natural selection, an optimization process that helps organisms become better suited to their environment. In some cases, this can be of engineering significance, when the traits being selected for are aimed at reducing energy consumption or performing a function engineers find interesting. However, evolution via natural selection maximizes the fitness of the organism as a whole; it does not optimize solely the specific performance characteristics of interest to engineers. Additionally, optimization via natural selection is countered by other evolutionary processes, such as mutation and genetic drift, that introduce diversity into populations. These processes also make it difficult to identify instances where the increasing prevalence of a trait in a population occurs as a result of natural selection. Finally, on a geologic time scale, macroevolution via natural selection occurs, possibly selecting for highly evolvable and adaptable blood lines capable of rapidly adapting to and surviving in changing environmental conditions. However, selection for these

64 characteristics is controversial, and these types of traits are much less likely to have applications in the design of improved engineering systems. Additionally, there is evidence that there is selection pressure, and hence optimization, for efficiency in a number of organisms and conditions, although this is not always the case.

65 Chapter 6: Sustainability-Related Benefits

53 out of 128 sources reference ‘sustainability in biology’ through statements such as: “Taking a biologically inspired approach, one abstracts ideas from nature, a sustainable system” [43]; “Emulation of the inherently sustainable living world through biomimetic design potentially offers one approach to creating sustainable or, at least, less unsustainable products” [28]; “Biological organisms, phenomena, and strategies… provide insight into sustainable and adaptable design” [119]. Some authors acknowledge that their beliefs that biology is sustainable are not proven. For instance, Vincent [71] states: “I make a single assumption: the biological system that we inherited on this planet is the paradigm for sustainability.” Quotations from accounts that referenced ‘sustainability in biology’ were grouped into three archetypal claims: (1) Biology has withstood the test of time – 9 sources; (2) Biology is environmentally sustainable (in general) – 9 sources; and (3) Biology has specific environmental advantages – 51 sources. The third archetypal claim is broken into 7 subsections, for each life cycle stage referenced: (3a) Biological organisms use renewable and abundant inputs – 9 sources; (3b) Biological materials are nontoxic – 2 sources; (3c) Biological organisms employ sustainable manufacturing processes – 15 sources; (3d) Biological organisms do not pollute – 5 sources; (3e) Materials in biology are recycled – 9 sources; (3f) Biological organisms are resistant to damage – 9 sources; and (3g) Biology is efficient – 42 sources. These claims and sub-claims are all depicted in the figure below.

Figure 13: All archetypal claims and sub-claims related to sustainability. The lower-level claims related to ‘Biology has a small environmental impact’ are not included in the diagram shown in the methodology section.

6.1 BIOLOGY HAS WITHSTOOD THE TEST OF TIME.

A number of authors define sustainability in the biological world as being related to life’s ability to endure [28] and persist [43] over billions of years. Nine sources state that biology is sustainable in this sense, and either reference the ‘lasting’ solutions in biology or the fact that biology has ‘withstood the test of time.’ The archetypal claim ‘Biology has withstood the test of time’ holds true when examined more closely; life has indeed persisted for billions of years. Biological organisms’ ability to collectively survive and remain on earth for such an extended period of time indicates that biology has the ability to sustain itself. Given the great diversity of life forms on the planet adapted to a wide range of environments, life is likely to continue to do so. However, many biological characteristics have changed significantly since the first organisms. Over the last 3.8 billion years, the environment has changed dramatically,

67 and the types of biological systems that inhabit the earth have likewise changed. Life as a whole has endured over this time period, but individual species for the most part have not. While it appears that there have been long periods of stasis in biology [145] where species remain relatively unchanged for millions of years [165], few of the organisms that currently exist – or the characteristics of these organisms – have truly withstood the test of the last billion years and have remained unchanged over this time period. The macroscopic traits of plants and animals frequently used as analogies in BID are far from the traits possessed by single-celled organisms billions of years ago.

Hence, if using biological analogies that have ‘withstood the test of time’ is truly critical for sustainable design (or BID in general), then perhaps only those characteristics shared by the first organisms that have truly persisted over these 3.8 billion years should be the focus of biological analogies. For instance, the molecular components of organisms – the genetic code and some metabolic pathways – are shared by a diverse range of organisms [166]. However, even the DNA recombination processes have changed, for instance, through sexual reproduction and the possible evolution of evolvability, discussed in Chapter 5. Additionally, it is incorrect to connect ‘withstanding the test of time’ to ‘having a small environmental impact.’ Doing so would be committing the logical fallacy of equivocation. Equivocation is a “verbal sleight of hand” where the argument shifts “between two senses of a word or expression” [167] and “the force of an argument depends on such shifts of meaning” [168]. The use of fallacious arguments using different definitions of the word ‘sustainability’ can lead authors to mistakenly conclude that BIDs are better for the environment than alternatives. For example, a very simple fallacious argument along these lines could be constructed as follows:

68 1. Biological systems are sustainable; life has survived over 3.8 billion years and has withstood the test of time. 2. Systems that are sustainable have a low environmental impact. ergo, 3. Biological systems have a low environmental impact. Because environmental sustainability in this context means having a small environmental impact, and this is not directly related to ‘withstanding the test of time,’ there is no reason to surmise that biology has a low environmental impact from the fact that it has withstood the test of time.

In conclusion, some biological organisms and features have ‘withstood the test of time’ and have remained essentially unchanged for billions of years. However, this is likely to represent only a small fraction of all potential analogies that could be used from biology. Additionally, thinking of sustainability in terms of ‘withstanding the test of time’ in this way is wholly unrelated to environmental impact; there is no reason to think that imitating a biological system that has remained unchanged for billions of years is any more likely to produce a concept with a smaller environmental impact than a biological feature that just evolved.

6.2 BIOLOGICAL ORGANISMS ARE ENVIRONMENTALLY SUSTAINABLE.

Nine sources refer to the archetypal claim ‘biology is environmentally sustainable,’ which is taken to mean: ‘biological organisms have a positive environmental impact,’ ‘biological organisms are unlikely to have a negative environmental impact,’ or ‘biological organisms have no environmental impact’. The analysis of this archetypal claim is divided into two sections, the first looking at human-related environmental impacts and the second dealing with non-human related environmental impacts.

69 6.2.1 Human-Related Environmental Impact

The introduction, preservation, or flourishing of biological organisms is frequently seen as having a positive environmental impact. For instance, the preservation of endangered species, such as the manatee, is typically regarded as ‘good for the environment.’ Tree planting and forest preservation is seen as part of many carbon control strategies in the face of climate change [169] and can even earn carbon credits under the Kyoto Protocol [170]. These examples may lead one to believe that the flourishing of biological systems, in general, is good for the environment. However, organisms used as natural resources by humans are commonly seen as having a negative environmental impact. Many biological systems that serve as resources for humans have had their life cycle environmental impacts studied, including intensive, extensified and organic grassland farming [171]; fish farms for rainbow trout, sea-bass, and turbot [172]; and production systems for dairy [173]; red meat [174]; corn grain and corn stover [175]; ethanol from corn, switchgrass, and wood; and biodiesel from soybeans, sunflowers [176], and microalgae [177]. These analyses make it clear that biological organisms used as natural resources can have a negative environmental impact. As was discussed in the section on environmental ethics in Chapter 2, biological systems include ‘non-desirable’ organisms that are threatening to humans and, consequently, their destruction can be seen as ‘good for the environment.’ For instance, the proliferation of parasites, bacteria, and viruses harmful to humans is typically viewed negatively and could certainly be considered ‘bad for the human environment.’ Jolliet et al. [51] likewise observe: “Growth of populations is generally seen as a benefit in the case of species with a historical trend towards extinction, whilst growth of invasive, ubiquitous species can be seen as a damage.”

70 Invasive species are another type of ‘non-desirable’ organism that is frequently considered to have a negative environmental impact. Although invasive species are not necessarily harmful [178,179], they frequently are regarded as having “negative impacts on the environment, human activities or human health” [179], “[n]egative interactions” with native species [180], as causing “economic or environmental damage” [3], and as being “aggressive” [178], particularly when the invasion is caused by human activity. For instance, Pimentel et al. [181] estimate that “[i]nvading alien species in the United States cause major environmental damages and losses adding up to almost $120 billion per year.” Additionally, because invasive species frequently have traits that make them better suited to an environment than native species, they can prevent native species from accessing resources, changing the established ecosystem dynamics with potentially disastrous consequences. Consequently, invasive species “pose major threats to biodiversity, ecosystem integrity, agriculture, fisheries, and public health” [179] and have caused “a massive biotic homogenization of the Earth’s surface” with “consequent devastation of the endemic biota of specific regions” [178]. In fact, estimates indicate that “42% of the species on the Threatened or Endangered species lists are at risk primarily because of alien-invasive species” [181]. Hence, the removal or destruction of invasive species is seen as being ‘good’ for the environment, the presence of invasive species is considered ‘bad’, and both are accounted for in LCAs. The United Nations Convention on Biological Diversity states that contracting parties should “[p]revent the introduction of, control or eradicate those alien species which threaten ecosystems, habitats or species” [54] to prevent further environmental damage. For example, the Australian government may award carbon credits to those who kill feral camels, because camels are responsible for significant damage to native animal and plant species and are responsible for carbon emissions 71 [182,183]. Additionally, Jolliet et al. [51] discuss how invasive species can be considered a damage indicator in LCA if the invasion is caused by humans. Consequently, it is clear that the proliferation of biological organisms in the context of human activity is not inherently or necessarily good for the environment. The preservation of ecological diversity is typically viewed as inherently good, as is the proliferation and protection of carbon-capturing species in the face of climate change. However, there are a number of organisms typically considered inherently bad – such as organisms that cause disease in humans – and their destruction is viewed as having a positive environmental impact. Many other organisms are considered bad in particular contexts; invasive species, for instance, can wreak environmental havoc on the ecosystems they invade.

6.2.2 Environmental Impact of Biology Unrelated to Humans

While it is uncommon to conduct an LCA on organisms in the wild, some wild organisms, particularly those referred to as ‘ecosystem engineers’ are frequently regarded by biologists as having significant environmental impacts. Ecosystem engineers physically change the environment “through their behavior or by virtue of their large collective biomass” [133]. They affect “the availability of resources to other species” [184] and “modify, maintain and create habitats” [8]. For instance, corals and trees change the environment through the presence of their physical structures, whereas woodpeckers and beavers affect the environment though the changes they make to materials [8].

Jones et al. [8] define the scale of the environmental impact of ecosystem engineers in terms of six factors: (i) Life time per capita activity of individual organisms. (ii) Population density. (iii) The spatial distribution, both locally and regionally, of the population. 72 (iv) The length of time the population has been present at a site. (v) The durability of constructs, artifacts and impacts in the absence of the original engineer. (vi) The number and types of resource flows that are modulated by the constructs and artifacts, and the number of other species dependent upon these flows. [8]

The environmental impact of ecosystem engineers can be both positive and negative, where positive impacts enhance “species richness and abundance” and negative impacts reduce these traits [185]. “For example, by modifying soils, the black rush Juncus gerardi increases species richness in some zones of New England salt marshes” [133], meaning its impact would be considered to be positive. Beavers, for instance, create habitats for some species while initiating environmental changes that destroy habitats of others [185]. However, Jones et al. argue that on a larger scale, the addition of a beaver-engineered habitat results “in a net increase in the number of habitat types, space, and resources for other species,” allowing a greater diversity of species to be supported in the same area [185] and that a similar environmental benefit will be seen in most other cases of ecosystem engineering.

Some organisms besides humans have had a significant and lasting impact on the global environment [8,131]. For instance, “early photosynthetic prokaryotes… introduced oxygen into Earth’s atmosphere”, allowing for the formation of the ozone layer and totally changing the global environment [99]. Additionally, “the production of the

‘greenhouse’ gas methane” by sauropod megaherbivores during digestion “could have been significant in sustaining warm climates” during the Mesozoic Era [186]. Hence, biological organisms in the wild can also have significant environmental impacts. These impacts can be both positive and negative, where positive impacts enhance, and negative impacts reduce, the richness and abundance of species.

73 6.3 BIOLOGY HAS SPECIFIC ENVIRONMENTAL ADVANTAGES.

51 sources claim that biology has a specific environmental advantage. This archetypal claim is broken down into 7 subsections, one for each type of environmental advantage referenced. These claims are: (a) Biological organisms use renewable and abundant inputs; (b) Biological materials are nontoxic; (c) Biological organisms employ sustainable manufacturing processes; (d) Biological organisms do not pollute; (e) Materials in biology are recycled; (f) Biological organisms are resistant to damage; and

(g) Biology is efficient. Each of these claims will be discusses separately below.

6.3.1 Biological organisms use renewable and abundant inputs.

Nine sources reference the claim ‘biological organisms use renewable and abundant inputs’. A number of sources mention that biology runs on sunlight [21,70,135,187,188], does not consume nonrenewable resources, such as fossil fuels [21,135,187], and only uses materials abundant in its environment [68]. Many sources marvel at the photosynthetic process and its ability to harness solar energy [21,189,190].

When researched further, it indeed appears that biological organisms are generally fueled by renewable and abundant inputs. In the commonly-accepted concept of a food chain, sunlight is the only initial energy input typically considered; in Golley’s [191] analysis of the energy dynamics of a food chain in old-field community, for instance, the only energy input included is solar insolation during the growing season. From a global perspective, the raw materials needed for photosynthesis – “sunlight, water and carbon dioxide” – “are available in almost unlimited amounts” [164], although this is of course not the case in all local environments, such as in deserts. Additionally, prosperous organisms are likely to rely on food found in abundance that is grown or produced through other biological processes, such as photosynthesis, and is, hence, renewable as well. 74 However, one could argue that there are exceptions to this rule, although these exceptions appear to be relatively rare. Some biological organisms use fossil fuels as energy inputs; for instance, hundreds of species of bacteria, cyanobacteria, and fungi are capable of using hydrocarbons as a source of carbon and energy [192]. Additionally, a number of species require the presence of other species in their environments, and these other species may not be abundant. For instance, a study examining seed bank dynamics of Oenothera deltoids ssp. Howellii, a highly endangered plant, found that the lack of hawkmoths or other effective pollinators in the environment hampered its reproductive success [193]. Hence, it appears that, in general, biology runs on renewable and abundant inputs, although there are a few rare exceptions to this rule.

6.3.2 Biological materials are nontoxic.

Two sources mention ‘non-toxicity in biology’ in their accounts of the benefits of BID, claiming that “organic materials…are self-assembled… with no toxic aftertaste”

[21] and, more specifically, that “natural materials for biological optical systems… are nontoxic” [194]. When examined using biological literature, it becomes apparent that this does not generally hold true. While there are numerous examples of non-toxic biological organisms and substances, there are also many examples of biological organisms that produce chemicals toxic to other organisms. For instance, some algal blooms release toxins poisonous to marine organisms and people [195]; “[m]any cyanobacteria are toxic to zooplankton” [196]; the seeds of the tree Aesculus californica are toxic to vertebrates [197]; plants used to make botanical insecticides contain compounds toxic to insects [198]; Sistrurus rattlesnakes have venom toxic to their prey [199]; the wasp Eulophus

75 pennicornis has venom toxic to tomato moth larvae [200]; and bombardier beetles squirt noxious chemical on their predators as a defense mechanism [123]. Hence, it does not appear that biological materials are generally nontoxic.

6.3.3 Biological organisms employ sustainable manufacturing processes.

Fifteen sources refer to the claim that manufacturing processes in biology are sustainable. Some refer to biology’s “Life-friendly manufacturing processes” [21], while others marvel at the production of biological materials at room temperature and pressure [68,69,73,127,154,201]. In addition, other authors focus on the low level energy inputs necessary to make materials in biology, such as ceramics [202], biocomposites [126], bone, collagen, and silk [69,154]. It is true that many manufacturing processes in biology occur at ambient temperatures and pressures. For instance, spiders produce silk at “close to ambient temperatures and pressures using water as the solvent,” unlike competing engineered materials such as Kevlar [15]. Additionally, coral create material with properties similar to cement at low temperatures and pressures; they extract calcium and magnesium from seawater and use it to produce their shells and reefs [203]. In this sense, many of the biological manufacturing processes could serve as examples for engineers to develop manufacturing processes at ambient temperatures and pressures, potentially making these processes more energy efficient. However, when examined more closely, it becomes apparent that some biological organisms produce materials at high temperatures and pressures. For instance, bombardier beetles, mentioned above, heat a mixture of noxious chemicals and water to 100 °C which they spray on predators [123]. Additionally, hydrothermal synthesis – “the synthesis by chemical reaction of substances in a sealed heated solution above ambient

76 temperature and pressure” – is believed to have played a significant role in the origin of life [204]. Finally, many thermophiles and piezophiles live, grow, and reproduce – i.e. they self assemble their bodies and produce offspring – in high temperature and high pressure environments, respectively. Piezophilic bacteria, such as deep-sea Shewanella violacea, [205] “possess optimal growth rates at pressures above atmospheric pressure” [206]. Bacillus stearothermophilus is a thermophilic bacterium that is found in the deep sea and has been shown in laboratory experiments to form colonies “between 39 and 70

C at atmospheric pressure and between 54 and 67 C at 45 MPa” [207].

Additionally, forming materials at low temperatures and pressures is not necessarily a requirement for sustainable manufacturing processes, nor is it a guarantee of sustainable manufacturing processes where present. The material synthesis occurring in organisms living inside volcanoes or at the bottom of the sea is unlikely to have a larger environmental impact than any other biological process; they just happen to make use of the physical realities of their environments in their materials synthesis process. Similarly, the fact that a manufacturing process in biology occurs at low temperatures and pressures does not guarantee that it has a low environmental impact; organisms may still be highly energy- or materials- inefficient in manufacturing, or they could produce toxins as a result of the biological ‘manufacturing’ processes, for instance.

A complete analysis of whether manufacturing in biology is sustainable, addressing the topics mentioned above, is outside the scope of this work. Such an analysis would likely involve in-depth research on a broad range of topics: (1) A formal definition of what ‘manufacturing in biology’ does, and does not, include; (2) An analysis of the movement of energy and materials through different types of food chains to gain an understanding of the macro-scale efficiency associated with ‘building’ different types of organisms, similar to Golley’s [191] study of the energy dynamics of an old-field 77 community food chain; (3) A micro-scale analysis of the energy and materials efficiencies of ‘self assembly’ in biology, e.g. a study of the metabolic cost of producing a skeleton, including “the actual calorific value of the skeleton, the work that has to be done to concentrate the raw materials in one place against a concentration gradient, and the work that has to be done in organizing the material once it is there” [208]; (4) An analysis of the outputs (wastes) associated with these processes; and (5) An analysis of many different types of ‘manufacturing’ processes performed by biological organisms in the context of tool use and animal artifacts – beaver dam construction, etc. – if deemed applicable. Hence, many manufacturing processes in biology could be considered ‘sustainable’ because they typically occur at low temperatures and pressures. However, there are a number of notable exceptions to this rule in biology. Additionally, having a low temperature and pressure does not guarantee that a biological process has a low environmental impact and would be considered ‘sustainable’. Finally, exploring the environmental impact of all biological manufacturing processes is an extraordinarily broad and complicated endeavor that is out of the scope of this text.

6.3.4 Biological organisms do not pollute.

Five sources claim that biology is a model for sustainability because non-human organisms do not pollute. Benyus marvels at biological organisms’ ability to perform functions that are desirable in engineering without polluting [21,187]. More specifically, Bar-Cohen discusses the biology’s ability to produce materials without emitting pollutants [69,127], and Paturi notes that plants are able to perform functions without generating air or noise pollution [209].

78 However, when a broader swath of literature is examined, it becomes clear that some biological organisms emit pollutants. One of the primary examples of pollutants produced by biological organisms is methane, a greenhouse gas produced by both “the anaerobic decay of organic matter in rice fields and natural wetlands” and “the anaerobic fermentation of organic matter in the rumen and lower gut of domestic and wild animals” [210]. Methane emissions from animals are recognized as having an environmental impact on par with those of human pollutants. Clark [183], for instance, compares the annual carbon dioxide equivalent emissions of camels, cows, and cars to a long-haul flight, as is show in the figure below.

Figure 14: Comparison of carbon-dioxide equivalent emissions from Clark [183], including those from camels and cows.

Similarly, Wilkinson et al. [186] compare methane production in sauropod megaherbivores in the Mesozoic Era to global methane emissions from cows, pre- industrial emissions, and current global emissions. They ultimately find that “sauropod megaherbivores could have been significant in sustaining warm climates” during the Mesozoic Era [186].

Figure 15: Comparison of methane emissions from Wilkinson et al. [186], including those from sauropods and cows.

Additionally, a 1986 estimate from Crutzen et al. [210] found that methane production by animals was “one of the most important individual sources within the tropospheric CH4 cycle,” making up “15-25% of the total tropospheric CH4 input,” with only emissions from rice fields and natural wetlands making up a potentially greater share. Furthermore, feces from animals are commonly considered pollution. Parveen et al. [211] state: “Estuarine waters receive fecal pollution from a variety of sources, including humans and wildlife,” and Geldreich and Kenner [212] discuss species of bacteria commonly found in animal feces that “may be considered a specific indicator of non-human animal pollution.” Fecal pollution is most frequently discussed in the context of its impact on human activities, such as the fact that it “can degrade water quality and restrict its use for harvesting sea foods, as well as recreational activities” [211].

Numerous other materials emitted by biological organisms could be considered pollutants, such as toxic releases from some algal blooms into the ocean [195] and the emission of CO2 by biological organisms during respiration.

80 Hence, some biological organisms do emit pollutants, and these emissions can have a large-scale effect on the atmosphere and environment globally.

6.3.5 Materials in biology are recycled.

Six sources mention the recycling of materials in nature, through statements such as: “Nature recycles everything” [21] and “all nature’s engineering products are fully recyclable” [213]. An additional three sources name examples of materials that are recycled in biology. For instance, Bar-Cohen discusses the food chain in which plants are eaten by herbivores, carnivores eat herbivores, and the bodies of carnivores decompose fertilizing plants [189]. Materials in biology could be said to be recycled when they are eaten by other organisms through predation or decomposition. When this occurs, the biological material is broken down and reused in another organism over a short time frame, the same way the material in a recycled aluminum can is broken down and used again. Along a similar vein, birds using fallen twigs for building nests could be considered an example of repurposing in biology, and the use of abandoned shells by hermit crabs [214] could be considered an example of reuse. However, there are numerous cases in which biological materials are not recycled, repurposed, or reused by other organisms on non-geologic time scales, as the engineering definitions of these terms imply. For instance, the accumulation of the bodies of dead organisms over geologic time periods appears to be more aptly likened to landfill disposal of waste than to recycling. For instance, fossil fuels are made from organisms that lived hundreds of millions of years ago; coal from the remains of trees and ferns, oil and natural gas from the remains of ancient marine organisms [215]. Similarly, the “shells, body parts and

81 dead tissues” of organisms “help form sedimentary rocks” [8]. Millions of years from now, landfills may serve an important geologic role as well, but that does not mean that human disposal of waste in landfills or the biological disposal of waste in geologic formations should be considered ‘recycling’. Additionally, the destruction of organic material by fire does not seem to be accurately likened to recycling; it more closely resembles the wasting of a potential energy source, such as the flaring of unwanted natural gas from an oil well, for instance.

While fires play an important ecological and evolutionary role, they do this in a somewhat more destructive way than the term ‘recycling’ suggests. Fires destroy most of the living vegetation and organic litter in their path. They “profoundly [alter] the supply of resources for many other species” [8], volatizing “some elements (notably carbon and nitrogen) while converting others into biologically more available, mobile forms” [216]. Fires do not breakdown the material in their path in order to maximize its usefulness to other biological organisms, the way recycling breaks down material for the purposes of maximizing its usefulness in other applications. They also cause a significant portion of biological material to become unusable by other organisms; hence, disposal of biological material in fires cannot be accurately likened to recycling. In conclusion, it appears that predation and decomposition can be likened to recycling. However, the accumulation of biological materials and their formation into fossil fuels or sedimentary rock, along with the burning of biological materials in wildfires, cannot be accurately described as recycling.

6.3.6 Biology is resistant to damage.

Eight sources appeal to the claim that biology is resistant to damage, through general statements referring to solutions in biology that “minimize damage profiles”

82 [121] or to specific biological organisms that are resistant to damage, such as drought- tolerant grasses [110] and the branched design of trees with reconfigurable crowns in high winds [217]. Upon inspection, it is clear that there is significant variation amongst species regarding how resistant they are to different types of damage. In coral reefs, for example, some species already show “far greater tolerance to climate change and coral bleaching than others” [218]. Hence, it seems likely that the findings from Chapter 5 on optimization in biology are relevant here. For each organism in question, one must analyze the traits and selective pressures that have been historically applied to the population to see if the population is resistant to a particular form of damage, or has likely been optimized to become resistant to this form of damage.

6.3.7 Biology is efficient.

42 sources appeal to the claim ‘biology is efficient’, through reference to “nature’s efficient design solutions” [62] and “highly effective and power efficient biological mechanisms” [69]. Also, BID literature describes many biological organisms and systems as energy or materials efficient, such as muscles [72,219,220], the legs of horses [111], and the sensory systems of plants and animals [98]. Literature from biology, discusses a number of examples of efficiency in biological organisms. For instance, shark skin is shape optimized to reduce energy loss while swimming; placoid scales, also known as dermal dentricles, with certain geometries and arrangements on the skin of sharks reduce frictional drag [18]. Jellyfish interact with their environment efficiently; they are able to attain high swimming speeds, while minimizing energy consumption, by releasing optimized vortices when water is ejected through their velum during swimming [16].

83 In addition, work from Vincent et al. [11] found that biological systems solve problems using information- and structure-based solutions, whereas problems encountered in technology are typically solved though energy manipulation. This implies that mechanisms in biology may be less likely to solve problems with the use of energy than typical engineering designs. However, biological organisms and systems are not all exceptionally efficient. As discussed in Chapter 5, many organisms waste materials and energy on body parts that are ‘useless’ and are present only as a result of the history of the evolutionary process; for instance, the ancient whale Basilosaurus had unnecessary ankle bones although it did not walk, and humans have tailbones although we do not have tails [131]. Additionally, some significant biological energy conversion processes have seemingly very poor energy conversion efficiencies; for example, the average conversion efficiency of photosynthesis globally is only 0.3% [221]. Furthermore, when energy conversion efficiencies of biological and engineered processes are compared directly, it does not appear that biological processes are more efficient than engineered ones. For instance, French [222] states: “Flapping wings appear to have poor propulsion efficiency compared with propellers or jets, and muscles are less efficient than piston engines or gas turbines.” Also, a table published in Tester [221] and adapted from Smil [223], reproduced below, makes a similar point, listing a wide range of anthropogenic and biological energy conversion efficiencies, the most efficient of which are anthropogenic.

84 Table 4: Efficiencies of Common Anthropogenic and Natural Energy Conversion Efficiencies from Tester [221] and adapted from Smil [223].

However, one cannot directly compare conversion efficiencies in biology to those in engineering because the processes serve very different functions. For instance, comparing the energy conversion of lactation in humans to the conversion efficiency of dry cell batteries is nonsensical. In addition, there is reason to believe that models of biological systems used by engineers in BID may frequently be more efficient than the biological organism they are 85 modeling. Weber et al. [224] observe that models of biological systems are frequently idealized, and when they compared the performance of real and idealized versions of cetacean flippers in water tunnel testing, they found that “[d]rag performance was significantly improved by idealization.” Hence, if a final design is more likely to be efficient when it has been inspired by an efficient analogy, a topic that will be covered in Chapter 7, engineers conducting BID may see this efficiency advantage either by carefully selecting an efficient biological analogy, or simply by modeling and idealizing the biological system.

Therefore, while there are many examples of efficient biological systems and evidence that biology is less likely to solve problems through energy manipulation than engineered designs, it is clear that biological organisms are not all exceptionally efficient and that biological energy conversion efficiencies are universally higher than conversion efficiencies in engineering. However, there is evidence that the idealized versions of biological systems used by engineers in BID are likely more efficient than the biological system they are modeling.

6.4 CONCLUSION

Some biological organisms and traits are sustainable in the sense that they have withstood the test of time; they have survived millions or billions of years, thereby proving their staying power. However, most biological systems have changed substantially over time, meaning their specific mechanisms have not been proven sustainable in this sense, at least not on the time scales of billions of years. Additionally, this form of sustainability is unrelated to environmental sustainability; just because biological organisms have ‘withstood the test of time’ does not mean they are more likely to have a low environmental impact.

86 The introduction, preservation, and flourishing of biological organisms is typically seen as having a positive environmental impact. In the field of LCA, common exceptions include biological organisms that are used as natural resources for humans and are considered to have a negative environmental impact. However, many organisms in the wild are regarded by biologists as frequently having a negative environmental impact, including invasive species and ecosystem engineers that reduce diversity in ecosystems. Additionally, the environmental impact of biological organisms – both positive and negative – can be on a global scale.

Finally, some claims made in the literature regarding specific environmental- impact related characteristics hold true while others do not. In general, biology runs on renewable and abundant inputs, although there are a few rare exceptions to this rule. It is not the case that biological organisms are generally nontoxic. Understanding the extent to which biological manufacturing processes are sustainable is an extraordinarily complicated issue, but it is clear that not all manufacturing processes in biology occur at low temperatures and pressures. Some biological organisms do emit pollutants, and these emissions can have a large-scale effect on the atmosphere and environment globally. It appears that predation and decomposition can be likened to recycling, but that the accumulation of biological materials and their formation into fossil fuels or sedimentary rock, along with the burning of biological materials in wildfires, cannot. Biological organisms are not universally resistant to the same types of potential damage. Finally, not all biological organisms are exceptionally efficient, and biological energy conversion efficiencies are not generally higher than conversion efficiencies in engineering.

87 Chapter 7: BID Benefits

46 of the 128 sources examined make claims directly about beneficial features found in BIDs. Quotations from these accounts were grouped into two archetypal claims and one sub-claim: (1) BIDs are optimized – 5 sources; (2) BIDs are sustainable – 43 sources, and (2a) BIDs are efficient – 12 sources. The tally for claim 2 includes the quotations related to sub-claim 2a. A diagram depicting the relationship between the claims is shown in the figure below.

Figure 16: Archetypal claims related directly to characteristics of BIDs.

This chapter is structured differently than previous chapters. First, each of the claims will be introduced briefly with example quotations. The remainder of the chapter will present caveats common to all claims.

7.1 BIDS ARE OPTIMIZED.

5 sources make statements related to the archetypal claim ‘BIDs are optimized.’ The only general statement to this effect is from Papanek [74] who asserts: “Through analogues to nature, man’s problems can be solved optimally.” The remaining quotations discuss examples of BIDs that perform well and exhibit desirable characteristics, such as dragonfly-inspired airfoils [225] and robotic swarms inspired by the division of labor in ants [68].

88 7.2 BIDS ARE SUSTAINABLE.

43 out of 128 sources appeal to the archetypal claim: ‘BIDs are sustainable’. 27 sources make general statements such as: “[B]iologically inspired materials and structured surfaces are eco-friendly or green with minimum human impact on the environment” [226]; “Emulation of the inherently sustainable living world through biomimetic design potentially offers one approach to creating sustainable or, at least, less unsustainable products” [28]; “Biological organisms, phenomena, and strategies… provide insight into sustainable and adaptable design” [119]; and “Biomimetics… challenges the current paradigm of technology and suggests more sustainable ways to manipulate the world” [227]. 16 sources provide examples of sustainable BIDs, claiming that designs for multifunctional reagents [228], architectural materials [188], and nanomembranes [229], for instance, offer potential life cycle impact advantages as a result of their bioinspired features.

7.2.1 BIDs are efficient.

12 sources refer to the sub-claim ‘BIDs are efficient,’ through statements such as: “It is believed that by utilizing natural systems… current engineering solutions can be made more efficient” [12]; and “Energy efficiency is one of the most important aspects linking biomimetic visions with living nature” [230]. Nine sources provide examples of energy-efficient BIDs, such as ventilation systems inspired by respiration in small birds and mammals [231] and ceramic processing inspired by energy-efficient materials synthesis in biology [202].

7.3 SUPPORT FOR ALL BID BENEFITS CLAIMS

Based on the many examples discussed in engineering literature, it indeed appears that some BIDs are optimized, sustainable, and efficient as a result of their bioinspired

89 features. Many other examples not included in the theoretical study will be discussed in detail in the upcoming chapters. Thus, these examples will not be discussed further here. The important takeaway is that there are many such examples.

7.4 CAVEATS COMMON TO ALL BID BENEFITS CLAIMS

However, the claims presented above – that BIDs are optimized, sustainable, and efficient – do not hold true for all BIDs. For instance, there is no reason to think that

Velcro, inspired by cockleburs [232], would be any more optimized, sustainable, or efficient than its non-bioinspired counterparts, such as buttons and zippers. Upon inspection, it is clear that the same set of factors plays a critical role in determining whether a BID will have a particular desirable characteristic, regardless of whether the characteristic in question is related to optimization, sustainability, or efficiency. Hence, the caveats to these three claims will be examined together. Factors that affect the likelihood of a BID possessing the desirable characteristic of interest include: (1) whether the designer is intentionally trying to produce a design with the desired characteristic, (2) whether the biological analogy possesses the characteristic in question, (3) how closely the biological analogy is being imitated in the engineering design, (4) whether the desirable feature is actually transferred to the engineering design, (5) whether the desirable feature retains its desirable properties in the engineering design, and (6) the nature of the unintended side effects of the desirable features in the engineering design. Each of these issues will be discussed separately below.

7.4.1 The designer should intentionally try to produce a design with the desired characteristic.

BID is not a magical methodology that will confer only desirable traits to final designs without effort on the part of the designer. Gruber et al. [230] echo this sentiment

90 when they warn that the “application of a biomimetic innovation method does not guarantee an ecological solution” and that “biomimetics… is not a panacea for all global problems.” Stachelberger et al. [229] do the same when they state: “there is no guarantee that a technical solution based on biomimetics will be ecofriendly,” as do Reap et al. [28] when they explain: “Emulation of the inherently sustainable living world through biomimetic design potentially offers one approach to creating sustainable or, at least, less unsustainable products… however… current approaches to biomimicry do not necessarily lead to such ends.” Haphazardly using a biological analogy in a design will not automatically result in improvement in one’s design. In cases where no optimization, sustainability, or efficiency advantage is intended by practitioners of BID, there is no reason to think that the bioinspired features will confer an optimization, sustainability, or efficiency advantage to the final design. Many BIDs – such as gecko-inspired robots and echolocation-inspired canes – fit this model; they involve the incorporation of many additional active energy systems inspired by the interesting functions observed in nature. In these cases, it is clear that the bioinspired features are causing the final engineering design to be more energy and materials intensive – albeit with an associated increased functionality – than the design was previously. This is because designers are using biological analogies as a way to perform novel functions, not to perform existing functions in a more optimized, sustainable, or efficient way. Hence, not all BIDs are optimized, sustainable, or efficient because these characteristics do not automatically result from using a biological analogy in the design process and because many designers are not trying to make their designs have these characteristics.

91 7.4.2 The pool of potential biological analogies should be scoped to those containing the trait of interest.

Not all biological analogies are created equal. As was established in Chapter 5, not all biological organisms and systems are optimized, let alone optimized for engineering parameters. Likewise, Chapter 6 showed that not all biological organisms and systems are sustainable, or possess specific sustainability-related characteristics, such as efficiency.

If a designer has decided to conduct BID for the purposes of generating optimized, sustainable, or efficient designs, (as opposed to more novel designs, for instance, as was discussed in Chapter 4), he or she hopes to learn from examples of optimization, sustainability, or efficiency in biology and use that information in the design process. Hence, the designer needs to scope his or her pool of potential biological analogies to only those that possess the characteristic of interest. Otherwise, there is no information related to optimization, sustainability, or efficiency from biology that the designer can use. For instance, if one is trying to design a more aerodynamic train profile to handle the change from low pressure to high pressure air for the purposes of enhancing energy efficiency, one would likely want to look at organisms that handle a similar pressure difference efficiently, i.e. one would want to compile information on a wide range of organisms that deal with high pressure to low pressure transitions – diving birds, jumping fish, dolphins, etc. – determine which of these handle the pressure differences efficiently, and then choose a profile based on this research. A wide range of tools are available to help designers find biological analogies relevant to their design problem. For instance, DANE, a Design by Analogy to Nature Engine provides a library of “Structure-Behavior-Function (SBF) models of biological and engineering systems” and has been used to aide designers in understanding biological

92 systems [233], as has a thesaurus for translating engineering functions to biological search terms [234]. However, there are no known tools that assist designers in scoping their pool of potential analogies to determine which have ‘optimized’, ‘sustainable’, or ‘efficient’ traits that may be advantageous to apply to their design problem.

7.4.3 One must focus on the relevant features of the selected analogy.

Similarly, designers should focus on the optimized, sustainable, or efficient features of the selected analogy. Every potential biological analogy has many different features that could be used in the design process. Different parts of the organism or biological system could be imitated on a wide range of length scales – from beak profiles, to chemical properties of a particular biological material, to its behavior while hunting in packs. When one has selected a particular biological analogy, and has verified that it contains the traits intended for the final design, it is critical that the entity actually being imitated contains this trait as well. There is no use in selecting a kingfisher for its efficient beak profile and then imitating its feathers, for instance.

7.4.4 How closely does the BID imitate the biological system?

If the BID does not closely resemble the optimized, sustainable, or efficient feature of the biological system, it seems unlikely these desirable characteristics would be transferred to the engineered design. Take, for instance, the example of a car frame inspired by bone growth. If the biological analogy were used very loosely, engineers could do a stress analysis and ensure that material in the car frame is located in areas that are stressed, as occurs during bone growth [235,236]. On the other hand, the analogy could be used very closely, and researchers could, for instance, grow the car frame from some sort of ultra-strong artificial bone. Feasible engineering solutions to this problem that take full advantage of the biological feature likely lie somewhere in the middle of 93 this continuum. The bioinspired structure of the Daimler-Chrysler bionic car, for instance, was created using bone growth-inspired stress analysis software. In any case, if the biological analogy is used in a very indirect way, the characteristics of interest in the biological analogy may not transfer to the engineering design.

7.4.5 Will the desirable trait in biology transfer to engineering?

The designer must ensure that the optimized, sustainable, or efficient features of interest can be transferred to engineering. A number of authors discuss the difficulties transferring desirable traits from biology to engineering. Vincent [71] states: “The transfer of a concept or mechanism from living to nonliving systems is not trivial. A simple and direct replica of the biological prototype is rarely successful, even if it is possible.” Muller [237] agrees, noting the “objective difficulties… in accommodating the differences in energy… between biological and human-made systems.” In the case of Sharklet AFTM, for instance, which is “manufactured using a photolithographic process… current manufacturing processes mean that… Sharklet AFTM cannot match the topographic and dimensional complexity of real dermal denticles” [238]. In some cases, such issues in manufacturing biological features may prevent beneficial characteristics of biological analogies from transferring to engineering.

7.4.6 A desirable biological trait may not continue to be desirable in a BID.

Context matters. Even if the desired characteristics of a biological analogy transfer to engineering, these characteristics may not prove desirable in the design.

Although the laws of physics still apply to biological organisms [103,239], the constraints facing biological organisms may be very different from the constraints facing engineered products [120]. Biological systems are optimized “for very specific needs and circumstances that may not reflect our requirements and unique capabilities” [240], 94 meaning they may be unsuitable for replicating directly in engineering applications. Muller [237] agrees, observing that biological organisms are “special-purpose designs” evolved to meet a specific set of constraints present in their environments, and consequently they “require additional work to arrive at general principles.” Biological traits are optimized for – or are sustainable/efficient in – a particular environmental context. For instance, the same traits that make a polar bear ‘optimized’ for the arctic winters prove detrimental in warmer climates [241], and the same mongoose lives sustainably in its native habitat but proves environmentally detrimental in regions where it is an invasive species and has caused the local extinction of a number of birds, reptiles, and amphibians [242]. Just as in biological systems, the environmental impact of a product varies greatly depending on the particular environmental conditions where it is used. Reap et al. [243] make a similar point when they state, in the context of LCA: “Each environment affected by resource extraction or pollution is, to a greater or lesser extent, unique. As a result, each local environment is uniquely sensitive to the stresses placed upon it by a particular product system’s life cycle.” For instance, the amount of energy required to brew tea in an electric kettle changes depending on the climate where the kettle is used, due to the altered initial temperature of the water [244].

By translating biological features to engineering, designers remove the biological features from the environments in which these features were beneficial. Bioinspired products are not used exclusively in the ecological niches of the organism that inspired them. A designer ought to consider whether the optimized, sustainable, or efficient traits from biology will continue to prove efficient in the intended engineering context, e.g. they should question whether reef coral’s method of manufacturing cement at low temperatures and pressures – which is sustainable in contexts with unlimited seawater 95 [203] – really would prove sustainable in the desert environment where the cement factory is planned.

7.4.7 Even beneficial features can have unintended detrimental effects.

Bioinspired optimization, sustainability, or efficiency advantages in engineering designs may be countered by other, unintended effects that make the final design less desirable as a whole. Just as in non-bioinspired sustainable design, most sustainability- related features involve an environmental tradeoff. Whether the feature ultimately reduces the environmental impact of the product depends on how the inclusion of the feature affects other aspects of the product and other life cycle phases. A number of authors discuss this issue in the context of sustainability. Benyus [187] explains how the biomimetic process can result in an environmentally and socially unsustainable product when, for instance, a bioinspired feature is mimicked, but no attention is paid to the life cycle impact of other aspects of the product, such as in materials and transportation. Along a similar line, work from Raibeck et al. [27] and

Reap et al. [28] has shown that the entire product life cycle must be considered to determine whether a particular bioinspired feature will confer a sustainability advantage to the product. A life cycle inventory study of a lotus-inspired self cleaning surface found that the energy and resource efficiency gained by the bioinspired surface during cleaning was countered by the increased need for resources and energy for the production of the surface, ultimately resulting in no clear efficiency or environmental impact advantage over the product’s life cycle [27].

Hence, designers must consider the potential unintended consequences of including a desirable feature.

96 7.5 CONCLUSION

While some BIDs are optimized, have reduced environmental impacts, or are energy efficient as a result of their bioinspired features, this is not generally the case; many bioinspired features are unrelated to these advantages, and those that are related only confer these advantages in certain contexts. More specifically, the likelihood that desirable optimization-, sustainability-, or efficiency-related advantages will transfer to BIDs increases when: (1) the designer intends to produce a design with these characteristics, (2) the selected biological analogy contains the trait of interest, (3) the biological features imitated in the BID also contain the trait of interest, (4) the BID closely imitates the desirable trait from biology, (5) the desirable trait is able to be transferred to engineering, (6) the desirable trait can continue to be desirable in a BID, and (7) the desirable trait has few, if any, unintended effects on the engineered design that counter the beneficial features conferred by the bioinspired trait.

97 Chapter 8: Theoretical Section Conclusion

Chapter 8 concludes Section 1, which examined the claimed benefits of BID through careful review of biological and engineering literature. Chapter 3 presented the methodology for the theoretical study and an overview of the claims identified. Chapters 4 though 7 examined these claims related to ideation benefits, optimization in biology, sustainability in biology, and advantages that translate to BIDs themselves, respectively. This chapter is broken into four sections. First, a summary of the findings from the BID benefits study is presented. Second, claims that were identified during the course of conducting the study, but were not analyzed, are briefly discussed. Third, the implications of the theoretical study’s findings regarding what constitutes a biological system in the context of BID are addressed. The section concludes with an overview of the theoretical study and places it in context.

8.1 SUMMARY OF FINDINGS FROM BID BENEFITS STUDY

A summary of all claims examined in Section 1 and the related analysis is provided in the table below.

Table 5: Summary of Findings from Theoretical BID Benefits Study.

Claim Findings 1. BID helps designers generate All design-by-analogy (DbA) techniques, including BID, produce novel ideas. more novel concepts than standard techniques. BID may be less likely to prompt design fixation than DbA using patents, but information in biology may be more difficult to translate to engineering.

2. Quantity: Biology contains Millions of species could serve as analogies in BID. However, many many potential analogies. biological organisms have yet to be discovered and are therefore inaccessible to engineers. Also, more patents have been filed worldwide than there are species, meaning this is not an advantage over DbA using patents.

3. Variety: Biology is diverse. Yes, but it is unclear whether there is greater diversity in biology or engineering and, hence, whether this is an advantage over DbA using patents. 98 Table 5, cont.

4. Relevance: Biology solves At least according to the engineers who make this claim and those problems engineers would who use biological analogies, biology contains solutions relevant to like to solve. the problems engineers want to solve.

5. Biology solves problems Preliminary evidence using analysis from TRIZ supports this claim. differently than engineering. 6. Biology is optimal. Although many examples of well-adapted biological organisms exist, organisms are not perfectly adapted for their environments. They frequently have features that serve no purpose, and they lack features and combinations of features that would be highly beneficial to them. Also, since the environment is constantly changing, it is not possible for them to be perfectly adapted to their environments at all times.

7. Biology is optimized by Natural selection helps organisms become better suited to their evolution via natural environment. In some cases, this can be of engineering significance, selection. when the traits being selected for are aimed at reducing energy consumption or performing a function engineers find interesting. However, evolution via natural selection maximizes the fitness of the organism as a whole; it does not optimize solely the specific performance characteristics of interest to engineers. Additionally, natural selection is countered by other evolutionary processes, such as mutation and genetic drift, that introduce diversity into populations. On a geologic time scale, macroevolution via natural selection occurs, possibly selecting for highly evolvable and adaptable blood lines capable of rapidly adapting to and surviving in changing environmental conditions. However, selection for these characteristics is controversial, and these types of traits are much less likely to have applications in the design of improved engineering systems.

8. Biology is optimized for There is selection pressure, and hence optimization, for efficiency in efficiency. a number of organisms and conditions, although this is not generally the case.

9. Biology has ‘withstood the Some biological organisms and traits have survived millions or test of time’. billions of years, thereby proving their staying power. However, most biological systems have changed substantially over time. Additionally, ‘withstanding the test of time’ is unrelated to environmental sustainability.

10. Biology is environmentally The introduction, preservation, and flourishing of biological sustainable. organisms is typically seen as having a positive environmental impact. Common exceptions are organisms used as natural resources for humans. However, many organisms in the wild are regarded by biologists as having negative environmental impacts, including invasive species and ecosystem engineers that reduce diversity in ecosystems.

99 Table 5, cont.

11. Biological organisms meet specific GDGs: a. Biological organisms use In general, biology runs on renewable and abundant inputs, although renewable and abundant there are a few rare exceptions to this rule. inputs. b. Biological materials are It is not the case that biological organisms are generally nontoxic. nontoxic. c. Biological organisms Understanding the extent to which biological manufacturing employ sustainable processes are sustainable is an extraordinarily complicated issue, but manufacturing processes. it clear that not all manufacturing processes in biology occur at low temperatures and pressures.

d. Biological organisms do Some biological organisms do emit pollutants, and these emissions not pollute. can have a large-scale effect on the atmosphere and environment globally.

e. Materials in biology are Predation and decomposition can be likened to recycling, but the recycled. accumulation of biological materials and their formation into fossil fuels or sedimentary rock, along with the burning of biological materials in wildfires, cannot.

f. Biology is resistant to Biological organisms are not universally resistant to the same types damage. of potential damage.

g. Biology is efficient Not all biological organisms are exceptionally efficient, and biological energy conversion efficiencies are not generally higher than conversion efficiencies in engineering.

12. BIDs are optimized. While some BIDs are optimized, have reduced environmental impacts, or are energy efficient as a result of their bioinspired 13. BIDs are sustainable. features, this is not generally the case; many bioinspired features are unrelated to these advantages, and those that are related only confer a. BIDs are efficient. these advantages in certain contexts. More specifically, the likelihood that desirable optimization-, sustainability-, or efficiency- related advantages will transfer to BIDs increases when: (1) the designer intends to produce a design with these characteristics, (2) the selected biological analogy contains the trait of interest, (3) the biological features imitated in the BID also contain the trait of interest, (4) the BID closely imitates the desirable trait from biology, (5) the desirable trait is able to be transferred to engineering, (6) the desirable trait can continue to be desirable in a BID, and (7) the desirable trait has few, if any, unintended effects on the engineered design that counter the beneficial features conferred by the bioinspired trait.

100 8.2 OTHER CLAIMS IDENTIFIED BUT NOT ANALYZED

Some other ideas have been proposed in the literature, but are mentioned only rarely, such as the potential for BID: to aid in the customization of technology [104], to improve complex products [245], and to help create multifunctional, [137,144], interdependent [144], more user-friendly [127,154], simpler and more elegant designs [67,127]. Additionally, authors make a wide range of other claims: that exposing people to biology through BID will make them more likely to care about sustainability

[137,246], that humans have learned from nature how to survive on earth and “secure a sustainable future” [69,127], that biological materials are biodegradable [69,127,154], that symbiosis in biology prevents resource depletion [21], and that biological organisms themselves are novel [139] and innovative [67]. These claims were not analyzed because few authors appealed to them. In contrast, many sources appealed to the idea that BID has been successful in the past. Authors in BID make statements such as: “Humans have borrowed many ideas from biology for design” [115]; “Many successful biomimetic designs support the notion that biology is a good source of analogies” [94]; and “Many elegant solutions to engineering problems have been inspired by biological phenomena” [247]. Additionally, numerous sources cite examples of technically and commercially successful BIDs, such as Velcro. The claim ‘BID has been successful’ was not analyzed formally in the study because its truth is evident to anyone familiar with the field of BID.

8.3 WHAT COUNTS AS A BIOLOGICAL ANALOGY IN BID?

In the process of conducting the theoretical study, it became apparent that there are some unresolved issues in the field concerning what constitutes a legitimate biological analogy in BID. The findings from the BID benefits study have implications that can be applied to these issues. 101 8.3.1 Genetically Modified Organisms and Human Selection

Should genetically modified organisms (GMO) or organisms subject to human selection processes, such as dogs, count as a biological system or an engineered one in the context of BID? If it were true that evolution via natural selection optimizes organisms for engineering parameters, or that biological organisms automatically possess certain sustainability-related benefits, then a designer may not wish to use a GMO or a species that has clearly been subject to human selection processes. However, the analysis in Chapters 5 and 6 shows that these generalizations do not hold. Hence, the benefits of using a GMO or an organism subject to human selection are just as likely to produce a BID with advantageous features. In fact, since GMOs and organisms subject to human selection have somewhat more conscious intent, it may be clearer to the designer what these organisms have actually been selected – or ‘optimized’ – for.

8.3.2 Extinct Species

As discussed in Chapter 5, a number of BID authors claim that ‘fossils are failures’ and organisms currently living have features that make them better suited for life on earth. Authors who ascribe to such a view would not consider extinct species to be legitimate biological analogies because they do not believe extinct species possess the desirable characteristics that make the use of biological analogies in the design process advantageous. For instance, some argue that the evolution over billions of years has optimized organisms currently living. Since extinct organisms have not survived ‘optimization’ via evolution, it would not be appropriate to use extinct species when conducting BID. However, Chapter 5 showed that organisms can go extinct for a number of reasons unrelated to their suitableness from an engineering standpoint. It also showed that the evolution via natural selection over shorter time periods to help a species become 102 better adapted to a particular ecological niche is the type of optimization in biology related to engineering parameters, not evolution over billions of years. Hence, the use of extinct species in the design process is just as likely to produce a beneficial engineering design as the use of a living species.

8.3.3 Tools and Artifacts of Animals

“Science has documented a number of bona fide cases of tool use by nonhuman species, such as apes, sea otters, birds, and insects” [1]. Do the buildings, tools, and artifacts of animals count as ‘biology,’ in the context of BID? The answer has implications for some of the frequently-cited examples of BID, such as Eastgate Centre’s cooling system, inspired by termite mounds, not termites themselves. On one hand, some biologists view tools and artifacts as part of an organism’s biological system that plays an important evolutionary role and has an impact on a creature’s fitness. “[P]roducts of animal engineering [are] extensions of species' phenotypes and hence subject to natural selection, including caddis-fly cases, termite mounds and birds' nests” [8]. If the source of the value of BID lies in the evolutionary process, then the tools and artifacts that evolve with creatures - such as termite mounds, beaver dams, monkey sticks, the stones Egyptian vultures drop on eggs [248]– would all be considered. Termites have evolved to build mounds that allow for proper ventilation and maintain appropriate temperatures; mounds with temperatures too high or too low are likely to harm the termites’ ability to survive and reproduce. Additionally, like biological systems, the tools and artifacts used by most non-human biological systems are made of plentiful, locally-available materials and run on sunlight. Consequently, it would seem as though these things have a place as analogies in BID and sustainable BID.

103 On the other hand, this framework would also lead one to include the tools and artifacts of humans, since humans are also animals. “Genetically, anatomically, behaviorally, and socially, we have been shaped through natural selection into tool makers and tool users” [1]. Hence, Hummers, data centers that require lots of cooling located in Nevada, swimming pools, paper processing, batteries, landfills, cell phones, bottled water, plastic shopping bags, and lawn fertilizers should all be included. This is an unintuitive result.

8.4 FUTURE WORK

Biology is a complex and fascinating field, and there are many topics that merit further research by those interested in developing effective BID tools and methodologies. In particular, a number of topics arose during the writing of this work related to optimization in biology that could be explored more fully. Despite fear that doing so will perpetuate more myths about biology that have not been fully researched, these topics are outlined briefly below.

It could be highly beneficial to restrict one’s pool of potential biological analogies to those that have proven adaptively significant, i.e. traits that arose via natural selection and hence confer a fitness advantage to the organisms that possess them. As was previously discussed in Chapter 5, it is not always easy to identify instances of adaptively significant features because of other forces, like biased mutation, that cause non-adaptive traits to increase in frequency in a population. However, developing a better understanding of mutation rates and how they can be used to identify cases of true optimization in biology may prove beneficial. Hodgkinson and Eyre-Walker [149] state: “Characterizing variation in the rate of mutation… is key to many questions in evolutionary biology, including… the detection of adaptive evolution.”

104 Additionally, ‘key innovation’ is a term in biology that refers to evolutionary modifications in structure or function that allow a lineage to “exploit the environment in a new or more efficient manner” [131] or that are “aspects of organismal phenotype that promote diversification” and ultimately “may enhance competitive ability, relax adaptive trade-offs or permit exploitation of a new productive resource base” [249]. Upon a brief analysis, this appears to be very similar to, or the same as, an adaptively significant trait. Examples include the evolution of wings, which opened “novel adaptation zones… for ancestors of birds and bats” [131]. Assuming this is indeed the case, by including the search term ‘key innovation’ in their internet searches for appropriate biological analogies, for instance, engineers may be more likely to focus on functionally-significant features that confer a significant benefit to a particular species in a particular environmental context, either associated with increased functionality or increased efficiency. Finally, instances of morphological convergence could potentially point to biological features that have been optimized, and also might be more likely to be optimized for engineering parameters. ‘Morphological convergence’ “refers to cases where dissimilar body parts evolved in similar ways in evolutionarily distant lineages” [131]. For example:

The differences between bat, bird, and insect wings are evidence that each of these animal groups adapted independently to the same physical constraints that govern how a wing can function in the environment. The wings of all three are analogous structures. They are not modifications of comparable body parts in different lineages. They are different responses of dissimilar parts to the same challenge. [131]

When unrelated organisms evolve similar features, it seems much less likely that these features are arising in response to common physical challenges. The similarities between these organisms are likely to point toward some sort of optimum, if the same result keeps 105 appearing, the way starting an optimization problem with different initial conditions and arriving at the same conclusion indicates that one has found the true optimum. It also means that the design, which is ‘optimal’ in many different environments, is more likely to be optimal worldwide, the way engineered products strive to be – instead of just in one particular ecological niche, the way most biological organisms are optimized. Of course, all of these topics require much further research, but they may provide promising avenues for researchers wishing to take this work a step further.

8.5 CONCLUSION

By examining and qualifying the claimed benefits of BID, this section has contributed to the underlying theory of BID, a topic which few other authors have addressed in depth. It is critical to have such a theory to guide researchers in the BID community towards fruitful methodologies and procedures that best leverage biology in engineering design. While this work is undoubtedly imperfect, it hopefully can serve as a starting point to openly discuss assumptions and controversies in BID and eventually arrive at a comprehensive theory of how and why biology can be used to improve engineering designs. Now we shift our focus away from the claimed benefits of BID, towards an assessment of the actual sustainability-related benefits of BID, as observed through implemented designs.

106 Chapter 9: Research Methods to Find Trends in BIDs

Chapter 9 begins Section 2 of this work, which focuses on the identification of trends in existing sustainable BIDs. Chapter 9 presents the research methodology for the first empirical study. The purpose of this study is to analyze existing sustainable BIDs using green design guidelines (GDGs) to identify sustainability-related trends. To do this, a list of existing BIDs was compiled using two different search techniques. Information on the

BIDs was collected, and designs that did not meet selection criteria were eliminated. The remaining designs were then analyzed to identify their bioinspired sustainability solutions and find trends. This procedure is presented in Figure 17 and is discussed in detail below.

Figure 17: Overall research methodology for identifying sustainable design solutions in existing BIDs.

107 9.1 STEP 1: COMPILE A LIST OF BIDS

Two search methods were used to compile a list of existing BIDs – a general, ‘breadth’ search technique and a snowballing-type ‘depth’ search technique. These two methods were used to ensure that, to the greatest extent possible, the designs analyzed were a representative sample of BIDs of interest. For this study, only bioinspired physical products were considered. Consequently, bioinspired elements of computer science, artificial limbs, and bioinspired methods of social organization, for instance, were not considered.

9.1.1 Breadth Search

The breadth search involved searching for and comparing lists and databases of BIDs from general sources. This method was used to ensure that a wide range of bioinspired products were identified and to increase the variety in the final sample of BIDs selected for analysis. The technique used here is a form of nonprobability sampling, “a sampling technique in which units of the sample are selected on the basis of personal judgment or convenience” [250]. The disadvantage of nonprobability sampling is that “the probability of any member of the population being chosen is unknown” and “there are no appropriate statistical techniques for measuring random sampling error from a nonprobability sample. Thus, projecting the data beyond the sample is statistically inappropriate” [250]. These disadvantages apply in this study as well. While this search technique helps introduce breadth into the study, it does not guarantee that the final list compiled is truly representative of the population of existing BIDs.

The following general sources were used: Wikipedia’s page for ‘Bionics’ [10], AskNature.org’s database of biomimetic products [251], Bioinspiration and Biomimetics (vol. 6, no. 1 [252] and vol. 5, no. 4 [253]), and a Japan Times Online article “Natural by Design” [254]. Selected sources were read, and any examples of BIDs of interest 108 provided in these documents were recorded along with their biological analogy and source. Some of the sources selected for the general search are peer-reviewed, some not. Although content on sources such as Wikipedia is user-submitted and not peer-reviewed, it is acceptable for use in this case because the general search is followed by rigorous verification with peer-reviewed sources. The disadvantage of using untrustworthy sources at this stage is that there is a greater chance that the designs identified in these sources cannot be substantiated and will later be eliminated, wasting time. The advantage of using these sources is that they give a broad overview of the field and the types of designs available.

9.1.2 Depth Search

Subsequently, another search technique was used to ensure depth of results. This depth search technique is in some ways similar to the snowballing search technique used in the social sciences to hone in on relevant data. Snowball sampling is “a sampling procedure in which initial respondents are selected by probability methods and additional respondents are obtained from information provided by the initial respondents” [250]. Snowball sampling cannot be used as the only search technique because doing so could significantly bias the search. For instance, if the first BID found were dolphin- inspired boat hulls and the snowballing technique was then used, materials-based or dolphin-inspired designs would likely be substantially overrepresented in the sample. However, the snowballing technique identifies good potential designs more quickly than general search techniques. Snowballing searches were conducted based on keywords found in the promising results of the general search. For instance, the Wikipedia page for ‘Bionics’ used in the

109 general search, states: “Examples of bionics in engineering include the hulls of boats imitating the thick skin of dolphins” [255]. A Google search of “bioinspired dolphin boat hulls” provides two scientific articles related to BIDs. The first: “Analysis and Classification of Broadband Echoes Using Bio-inspired Dolphin Pulses” is related to dolphins, boats, and bioinspiration and provides the additional examples of a “biomimetic dolphin based sonar system” and “bio-inspired pulses developed from observations of bottlenose dolphins” [256]. The second: “Bioinspired Materials for Self-Cleaning and

Self-Healing” was related to bioinspired materials and provides the additional examples of “composite materials with nacre-like flaw tolerance,” “gecko-inspired reversible adhesives,” “advanced photonic structures that mimic butterfly wings,” self-cleaning materials inspired by the lotus leaf, self-healing materials “inspired by living systems in which minor damage (e.g., a contusion or bruise) triggers an automatic healing response,” self-cleaning windows, and self-cleaning boat hulls, among others [257]. Each of these potential BIDs can then be investigated in peer-reviewed literature. A simplified depiction of this search is shown in the figure below.

110

Figure 18: A snowball sampling search starting with the term “dolphin skin boat hulls” is more likely to return results related to dolphins or boat hulls than a randomly-selected and unrelated BID, like “gecko-inspired adhesives.” Photo credits:[258-263].

9.2 STEP 2: INFORMATION COLLECTION

A wide range of information was collected on the BIDs considered for analysis. This information is catalogued in ‘Design Library’ entries found in Appendices A-C. These entries include statements from designers, messages on product websites, patent claims, journal papers, and books. These sources tell the story of the bioinspiration process, explain how the design operates, identify competing products, describe how competing products operate, provide data on the environmental impact of either the BID or its competing product, and discuss the physical or biological principles that came into play during product design.

111 Most products analyzed have many different potential competitors. In general, only one competing product was chosen for comparative analysis, allowing for a more simplified comparison process. Without a specific competitor in mind, it would be very difficult to identify sustainability solutions in the BIDs. When there were multiple competing products, the following types of products were preferred: those with large market shares, those identified by the designer or company producing the BID as the intended competitor, those that were the most similar to the BID, and those with easily accessible information. For instance, in this analysis, self-cleaning surfaces inspired by the lotus leaf were compared to standard surfaces cleaned using spray and ultrasonic cleaning methods. These two competing methods were both selected because life cycle data was available to compare these three methods in a paper from Raibeck et al. [27]. Additionally, Eastgate Centre’s bioinspired passive cooling system was compared to an electric air conditioner for a building of a similar size in the same location.

9.3 STEP 3: SELECTING DESIGNS TO ANALYZE

The full set of selection criteria is provided in the table below. A detailed explanation of each criterion follows. During the information collection stage, if a design was found not to meet one of the criteria described below, it was set aside and not researched further.

112 Table 6: Design Selection Criteria

1. There must be documented evidence from reputable sources that the design is truly bioinspired.

2. The design must be feasible.

3. There must be evidence in peer-reviewed literature that the design has a reduced environmental impact as a result of its bioinspired feature in at least one stage of its lifecycle, compared to functionally-equivalent competing products.

9.3.1 Criterion 1: The design is bioinspired.

The first criterion, requiring documented evidence from reputable sources indicating the design is truly bioinspired, is used to ensure that all the designs analyzed belong in the population of BIDs. This criterion was deemed necessary because bioinspired status is not a measureable quality that can be determined by looking at the design itself. It is instead a quality related to the process undergone by the designer. Given the trendiness of bioinspiration and the enthusiasm people have for it, there is reason to believe that within the vast expanse of gray literature on the topic, some designs are misrepresented as bioinspired when, in fact, they are not. Additionally, even within the realm of authoritative literature on BID there are discrepancies between different researchers regarding whether specific designs should be considered bioinspired. For instance, Philip Ball, in a 2001 article in Nature [68], states that the Eiffel Tower was inspired by bone structure while Julian Vincent et al., in a 2006 article in Journal of the Royal Society Interface [11], state that there are myths that the

Eiffel Tower was inspired by the human femur or a tulip stem, but that it was actually just designed to resist wind loading. Neither source provides a citation for their statements. Logically, Ball and Vincent’s contradictory statements cannot both be right. Being

113 incorrect in this case has very little impact on the validity of the work of the authors; in both cases, the Eiffel Tower was used only as an example to illustrate what BID is (or is not). However, if this problem is a common one, it could have a large impact on studies, such as this one, that analyze many BIDs together. Firsthand accounts from designers or parent companies stating that a design is bioinspired constitute sufficient evidence to show that a design is truly bioinspired. Information of this type is frequently found in newspaper interviews with the product’s inventor, academic papers written by the inventor, patents and patent applications, and company websites. For instance, to show that Sharklet antibacterial surfaces are truly bioinspired, Sharket’s website [264], Sharklet patents [265,266], or peer-reviewed papers from one of Sharklet’s founders, Anthony Brennan [267], are all widely available and could be used. It is much more challenging to verify older designs, such as the Eiffel Tower, are truly bioinspired because the inventor can no longer be asked if these designs were bioinspired or not, and firsthand accounts of the design process are more difficult to find.

9.3.2 Criterion 2: The design is feasible.

The second criterion, that the design must be feasible, is included to ensure the findings of the study are limited to those sustainability characteristics that actually can be transferred to engineering. Frequently, the designs selected are commercially-available products or a fully-functional prototype, ensuring that they are indeed feasible. The additional benefit of designs that have clearly been established as feasible is the increased accuracy with which a product’s mechanisms and environmental impact can be ascertained. As will be explained in further detail shortly, GDGs are used in this study to compare the environmental impacts of two products. Since GDGs are used

114 instead of LCA, it is not necessary to have extremely detailed information on all stages of the products life cycle, as was discussed in Chapter 2. However, it is still incredibly beneficial to know what the final parts are, what material they are made of, how they are manufactured and assembled, whether they can be recycled, how much energy they consume during use, etc. Before a fully-functional prototype exists, many of these aspects of the product have not yet been determined. Hence using fully-functional prototypes and commercially available products likely greatly improves the accuracy of the assessment.

9.3.3 Criterion 3: Proof of a reduced environmental impact.

The third criterion is that there must be evidence in peer-reviewed literature that the design has a reduced environmental impact as a result of its bioinspired feature in at least one stage of its lifecycle, compared to functionally-equivalent competing products. Currently, it is trendy to label products as ‘sustainable’ and ‘bioinspired’ for marketing purposes; there is also a misconception that all BIDs are more sustainable than alternatives, as was discussed in Chapter 7. The third criterion is used to avoid products that, in fact, offer no proven environmental advantage as a result of their bioinspired features. For example, Velcro is truly a BID [232]. However, when compared to its competitors – buttons and zippers – there is no logical or fundamental reason why Velcro would offer a sustainability advantage. There is no evidence in peer-reviewed literature that Velcro has a reduced environmental impact compared to its competitors as a result of its bioinspired features. Consequently, Velcro is not included in the analysis.

9.4 ANALYZING INDIVIDUAL DESIGNS USING GREEN DESIGN GUIDELINES (GDGS)

After verifying that the BIDs met the three criteria stated above, and after all required information had been collected, the designs and their competing products were 115 analyzed using a compilation of 65 GDGs [61]. This analysis was performed by two researcher independently, using the ‘Design Library’ entries as a resource to learn about the features of the BIDs and their competing products. These GDGs are reproduced in Appendix D. The GDGs provide a way to compare the environmental impact of BIDs with their non-bioinspired equivalents, from the standpoint of a conceptual designer. It is advantageous to use GDGs instead of LCA tools for this purpose because GDGs are intended to be used during conceptual design, as are biological analogies, and GDGs are much faster to use than LCA tools.

For instance, Eastgate Centre, a shopping center and office building in Harare, Zimbabwe, constructed by Arup and designed by Pearce Partnership, was analyzed using the GDGs. Instead of having a standard industrially-sized air conditioner, Eastgate Centre is designed to have a passive cooling system, assisted by fans [29], that mimics cooling in termite mounds [33,30]. Heat from the building’s people and machinery rises, causing thermosiphon flow within the building; chimneys on the roof, above the boundary layer of the wind, prompt induced flow, drawing hot air out the chimney and cool air in at ground level [34]. According to Arup, Eastgate consumes approximately 50% of the energy consumed by a comparable building with an air conditioner in Harare [32]. For the purposes of this analysis, Eastgate Centre was compared to a theoretical similarly- sized office building in Harare with an industrial-sized electric air-conditioning system. Consequently, the reduction in energy consumption seen by Eastgate Centre is associated with a reduction in electricity consumption by the building.

In 2008, the most recent year for which data is available, approximately 53% of electricity in Zimbabwe came from hydropower, 46% from coal and peat, and the remainder from petroleum [268]. In general, hydropower is considered a renewable energy resource because the supply of freshwater in rivers that generate hydropower is 116 naturally replenished. However, these resources are vulnerable to climate change and extreme weather events, such as drought. Additionally, while the relative environmental impact of hydropower compared to other electricity resources is small, there are still significant carbon emissions associated with the construction of dams and flooding of land for dams, as well as an impact on wildlife in the rivers. Coal, peat, and petroleum are all nonrenewable fossil fuel resources. Coal and peat are relatively abundant in Zimbabwe while petroleum is not; over the last 40 years,

Zimbabwe has consistently been able to supply enough coal and peat to meet all of its own needs, but its oil demand has been wholly supplied by imported sources [268]. Coal, peat, and oil all have well-know environmentally-damaging effects, particularly with regard to greenhouse gas emissions.

Figure 19: Example GDG comparison. Photo credits: [36,37].

117 Eastgate performed better than this competing building with regard to five GDGs, three of which are depicted in the figure above and will be discussed further here. It performed better with regards to GDG #1:“Specifying renewable and abundant resources” [61], because air circulation in Eastgate occurs as a result of the buoyancy properties of the air and the geometric design of the building, allowing for a substantial reduction in electricity consumption when compared to an industrial air conditioning unit. The buoyancy of air is both renewable and abundant, compared to the electricity needed to power an industrial air conditioner. Eastgate meets GDG #11: “Specifying the cleanest source of energy” [61], better than a building with an air conditioning system for similar reasons, because it uses geometry and waste heat from buildings along with assisting fans instead of relying much more heavily on electricity from environmentally-damaging sources. Eastgate meets GDG #32:“Interconnecting available flows of energy and materials within the product or between the product and its environment” [61] better than the competitor because the waste heat from the building is used to drive thermosiphon flow, and the higher velocity of the air at the top of the chimney drives the induced flow. In contrast, air conditioners typically are stand-alone units, not designed to take advantage of the physics of site-specific fluid flows.

9.5 CONCLUSION

Chapter 9 presents the methodology used in the empirical study. This study is aimed at identifying trends in existing sustainable BIDs. This chapter covers the way in which a list of potential BIDs was compiled, the type of information that was collected for the considered designs, the criteria used to select designs for analysis, and the manner in which the environmental impact of BIDs and their competitors were compared.

118 Chapter 10: Data and Analysis of GDG Trends Study

Chapter 10 presents the data collected from the methodology presented in Chapter 9, along with analysis of the GDG-related trends present in the sustainable BIDs. This includes a list of BIDs compiled using the depth and breadth searches, the aggregate data from the GDG study, and a discussion of the results of the study in the context of other research.

10.1 BREADTH AND DEPTH SEARCH RESULTS

The results of the depth and breadth searches for potential BIDs are shown in Appendix F. The first six lines of this table are shown in the table below. The BID is listed, along with the biological system that inspired the design and a list of the sources that identify this design as ‘bioinspired’.

Table 7: The first six BIDs considered for analysis. The complete version of this list is provided in Appendix F.

Overall, 194 potential BIDs were identified, from 93 different academic and non- academic sources and 27 different authors. 95 potential BIDs were identified from the breadth search, with an additional 98 coming from the depth search. When a design was named in multiple sources during the breath or depth searches, it was counted only once. The list of designs has breadth; it represents examples from a broad range of fields – architecture, materials science, mechanical engineering, and electrical 119 engineering, to name a few. Additionally, the list of potential BIDs has depth; a number of the potential BIDs use the same biological analogies for different purposes, and a number perform the same task using different analogies.

10.2 HOW BIDS RESEARCHED IN DEPTH FARED AGAINST SELECTION CRITERIA

Of the 194 BIDs listed, only 30 were researched in depth to see if they met the criteria discussed in Chapter 9, due to time constraints and the lack of available information for some of the designs. A list of these 30 BIDs is provided in Table 8 below. The table is color-coded, with the color of the row indicating the extent to which the design met the three selection criteria. Green (rows 1-9) means the BID met all 3 criteria and was analyzed using the GDGs. Yellow (rows 10-22) means the design was researched, but it is still unclear whether it meets all criteria due to deficiencies in information collected. Grey (rows 23-28) means that the item was researched but did not meet all criteria. Red (rows 29 and 30) means the item may have a much larger environmental impact because of its bioinspired feature. An asterisk* in front of the number of the design indicates that there is a ‘design library’ entry for that the design in one of the appendices, as explained below.

10.3 DESIGN LIBRARY

The designs listed in the table above with an asterisk have a ‘design library’ entry in one of the appendices, where all information related to that design was collected and synthesized. Appendix A contains the design library entries for the nine designs presented above in green that were selected for GDG analysis because they met all three design selection criteria. Appendix B contains six entries for the designs presented above in yellow that were close to containing enough information to be analyzed, but lacked some significant detail. Appendix C contains three example entries for designs presented 120 Table 8: Designs researched thoroughly and how they fared against the selection criteria. # Design Inspired By Sources *1 Self-cleaning transparent thin film Lotus leaf [11,269-271] *2 Eastgate Centre cooling system Termite mound [35,269,271,274] *3 Biolytix filter Natural decomposition on a [275] river’s edge *4 Daimler-Chrysler bionic car - shape Boxfish [269,273,274,276] *5 Daimler-Chrysler bionic car - Initially, adaptive growth of [11,274,276,277] structure –SKO method trees; later bones *6 Interface Flor i2 Entropy carpet Forest floor [278,279] *7 Sharklet antimicrobial surface Shark skin [269,280,281] *8 Shinkansen 500 series nose cone Kingfisher [254,269,277,282] *9 Shinkansen 500 series pantograph Owl [254,283] *10 Airbus 320 Shark skin riblets [113,273] *11 Baleen water filters Blue whale [284] *12 Calera cement Skeletons of marine [285,286] animals *13 Geckel Geckos and mussels [270] *14 HotZone radiant heater Lobster eyes [287] *15 Passive walking bipedal robots Humans [273] 16 Adhesives Gecko feet [11,269,271,273] 17 Aircraft wings with reduced drag, Divided wing tip of birds [11,288] Airbus A380 with wings of low aspect ratio (buzzard, vulture, eagle) 18 Boat hulls Dolphin skin [271,273] 19 Mirasol color electronic screens Morpho butterfly wings [273,289] 20 Pelamis wave converter – The redundant vertebral [270] Aguacadoura wave farm units of snakes 21 Sonar/radar Echolocation of bats [271] 22 Wood glue without toxins - Secretions mussels use to [290] Columbia Forest Products cling to surfaces underwater *23 Crystal Palace in London Giant water lily [11,68,291] *24 Eiffel Tower Trabecular struts in the [68,11] head of a human femur or the taper of a tulip stem *25 Velcro Burs, burdock plant [11,269,271,273] 26 CAO Software Initially bones; later trees [274,276,277] 27 Sharklet Marine boat hull coatings Shark skin [281] 28 Sharklet Medical devices Shark skin [281] 29 Robocane Ecolocation [270] 30 Sonar system Dolphins [256,270]

121 above in grey that had sufficient information but did not meet all three criteria. These entries can be used as a reference for others trying to locate information on those designs in particular or locating large numbers of BIDs. Where available, the following information is presented in each design library entry: (1) an overview listing the BID, biological analogy, competing product, and environmental advantage of the BID, (2) a description of the biological analogy, (3) a description of the bioinspired feature, (4) quotations showing that the BID meets all three design selection criteria, (5) a description of the competing product, and (6) a written comparison of the environmental impact of the BID versus its competitor.

10.4 AGGREGATE DATA FROM GDG ANALYSIS

The environmental impacts of the nine BIDs that met all three selection criteria were compared to their non-BID competitors using the GDGs. A table presenting the full results of the GDG analysis with justification is provided in Appendix G. A summary of the results is provided in the table below. A green box with a ‘B’ indicates the BID met the GDG better than the competing product. A red box with a ‘W’ indicates the BID performed worse on the guideline. Likewise, a yellow box with ‘U’ indicates it is unclear which is better but there is reason to believe there could be a difference, and an empty box implies that no difference is anticipated.

122 Table 9: Summary of GDG Analysis, Organized by both GDG and BID.

Part 1: GDGs 1-33 Part 2: GDGs 34-65

# 1 2 3 4 5 6 7 8 9 # 1 2 3 4 5 6 7 8 9

OR'stiles carpet entropy

Chrysler Concept Car ChryslerShape Concept Car ChryslerStructure Concept Car ChryslerShape Concept Car ChryslerStructure Concept

- - - -

et Antimicrobial Surface etAntimicrobial

Cleaning Surface Cleaning Surface Cleaning

Series Shinkansen Pantograph Shinkansen Series

- -

Green Design Guidelines (GDGs) GreenGuidelines Design 500 cone nose Shinkansen Series 500 Daimler Daimler System EastgateCooling Centre Self Surface Antimicrobial Sharklet Filter Biowater Biolytix InterfaceFL (GDGs) GreenGuidelines Design Pantograph Shinkansen Series 500 cone nose Shinkansen Series 500 Daimler Daimler System EastgateCooling Centre Self Sharkl Filter Biowater Biolytix InterfaceFLOR'stiles carpet entropy 1 B B B 34 2 B 35 3 36 4 B 37 5 B 38 6 39 7 W 40 B 8 B B 41 B B U 9 B B B 42 B 10 U U B 43

11 B B 44

12 45 B 13 46 14 47 15 48 16 49 17 B 50 18 B B 51 19 W 52 20 B 53 21 54

22 W 55 W GreenGuidelines (GDGs) Design 23 56 24 W 57 25 B U B 58 B 26 59 27 B B 60 28 B B B B B B B 61 29 62 30 63 31 64 32 B B B 65

123

Similarly, a summary of the GDGs met better by each of the BIDs, organized by BID, is provided in the table below.

Table 10: GDGs met better by the BIDs.

GDGs Met Bioinspired Design Comparison Product Better By BID 1, 2, 4, 9, 10, 18, Biolytix Filter Septic tank 25, 28, 32, 41 Shape of BMW 3 Series Daimler-Chrysler Bionic Car Shape 28 Sedan Daimler-Chrysler Bionic Car Structure Standard car frame 17, 18, 27, 28

Eastgate Centre Cooling System Electric air conditioner 1, 11, 28, 32 Conventional modular Interface FLOR i2 Entropy Carpet 5, 20, 40, 45, 58 carpet Standard surface, spray 1, 9, 11, 25, 27, Self-Cleaning Transparent Thin Film and ultrasonic cleaning 28, 32 Clorox disinfectant Sharklet Antimicrobial Surface 9, 41, 42 bathroom cleaner Shinkansen 300 Series Shinkansen 500 Series Nose Cone 8, 28 nose cone Standard pantograph Shinkansen 500 Series Pantograph 8, 28 without serrations

A number of trends were uncovered related to the GDGs that were most frequently met superiorly by the BIDs compared to their non-BID competitors. Seven out of 9 BIDs met GDG #28: “Specifying best-in-class energy efficiency components” [61] better than competitors. For instance, Eastgate Centre met GDG #28

better than an office building in Harare of similar size with an electric air conditioner because less active energy needed to be brought into the system to get the same amount of cooling [32].

124 Additionally, 3 GDGs were met better by the BIDs as a result of their bioinspired features for 3 out of 9 design pairs: (1) GDG #1: “Specifying renewable and abundant resources,” (2) GDG #9: “Specifying non-hazardous and otherwise environmentally “clean” substances, especially in regards to user health,” and (3) GDG #32: “Interconnecting available flows of energy and materials within the product or between the product and its environment” [61]. For instance, Biolytix met GDG #32 better than non-BID alternatives because the flow of waste material through the system is interconnected with the filtration function. As the waste is filtered, it becomes the humus, which then serves as the filter for the next batch of waste [292]. Additionally, the Biolytix system itself – which is filled with worms and insects – functions much as a miniature soil ecosystem, where the living organisms that are a part of the product are interconnected with the filtering and treatment functions to a greater extent than occurs in standard septic systems [293,292]. Finally, 6 GDGs were met better by 2 out of 9 BIDs: (1) GDG #8: “Installing protection against release of pollutants and hazardous substances,” (2) GDG #11: “Specifying the cleanest source of energy,” (3) GDG #18: “Specifying lightweight materials and components,” (4) GDG #25: “Implementing reusable supplies or ensuring the maximum usefulness of consumables,” (5) GDG #27: “Minimizing the volume and weight of parts and materials to which energy is transferred,” and (6) GDG #41: “Ensuring minimal maintenance and minimizing failure modes in the product and its components" [61]. For example, lotus-inspired self-cleaning surfaces met GDG #25 better than standard surfaces that were spray cleaned or cleaned using ultrasonic aqueous cleaning methods because self-cleaning surfaces minimize the volume of water consumed during cleaning [27]. Additionally, the structure of the Daimler-Chrysler bionic concept car met GDG #27 because the bioinspired SKO method reduces the weight of the car’s 125 frame [41,294]. Since energy is transferred to the frame in the process of moving the car, the bioinspired frame minimizes “the weight of parts and materials to which energy is transferred” [61]. A diagram depicting these guidelines most frequently met better by the BIDs, compared to their non-BID competitors, is shown in the figure below.

Figure 20: Trends related to the GDGs most frequently met better by the BIDs than their competitors.

126 10.5 VALIDATION OF GDG RESULTS

The GDG analysis was validated by having different researchers independently conduct the analysis and through the comparison of their combined results with related work of others in the BID community.

10.5.1 Independent Raters

The GDG analysis was performed independently by two researchers – the author and an undergraduate mechanical engineering student – to ensure the repeatability of the results. Both researchers had access to the design library entries for the designs analyzed, the sources cited in the design library entries, and Telenko’s master’s thesis [61], which contains a detailed explanation of each GDG with examples. Both researchers also performed internet searches to better understand the designs. The analysis for Eastgate Centre was provided as a training example to the undergraduate researcher and, consequently, was not arrived at using this method. After the GDG analysis had been performed independently, the results of the two raters were compared, and areas of disagreement discussed. Most disagreements in ratings were caused by differing interpretations of the GDGs. For instance, one rater interpreted GDG #25: “Implementing reusable supplies or ensuring the maximum usefulness of consumables” [61] as applying to cases in which the need for energy inputs was reduced. In this case, the rater interpreted energy inputs as ‘consumables.’ Upon consultation with the other rater and others more familiar with the guidelines, it was determined that energy would not be considered a ‘consumable’ in this sense, and the reduction in energy inputs would instead be accounted for under GDG #28: “Specifying best-in-class energy efficiency components” [61]. Most other disagreements had to do with differences in information concerning the designs themselves. These disagreements were quickly resolved with the other rater reading the source containing the information 127 of interest and a collective judgment being made related to the new source’s legitimacy and the information’s relevance to the guideline in question.

10.5.2 Comparison of Results with Other Work

In some cases, it was also possible to validate the results of this study using the work of other researchers. In particular, a 2010 paper from Wadia and McAdams [62] and Wadia’s 2011 thesis [63], both discussed in Chapter 2, present studies where BIDs were analyzed and either biomimetic design guidelines [62] or biomimetic design principles [63] were generated. Additionally, this work analyzes some of the same BIDs analyzed here – including Eastgate Centre, the shape of the Daimler-Chrysler bionic concept car, the nose cone of the Shinkansen train, the lotus-inspired self-cleaning surface, and the Shinkansen’s pantograph. Specifically, one of the biomimetic design principles presented in Wadia [63] – “Use materials and/or energy from the environment to help the product/system accomplish its function” – and one of the biomimetic design guidelines from Wadia and

McAdams [62] – “Interact with and use environment versus isolation” – seem to get to the heart of GDG #32 – “Interconnecting available flows of energy and materials within the product or between the product and its environment” [61]. The examples Wadia [63] provides for biomimetic design guideline discussed here include Eastgate Centre, the lotus plant, and shark dentricles. This indicates that Eastgate Centre should likely meet GDG #32, and that transparent thin films inspired by the lotus leaf and Sharklet may likely meet this guideline as well, since their biological analogies likely meet GDG #32.

Here, Eastgate Centre and the self-cleaning transparent thin film were both found to meet GDG #32 better than their comparison products, but Sharklet did not. This discrepancy can be explained by the description Wadia provides explaining why shark dentricles meet

128 the biomimetic design guideline. He states: “The shark uses the water flowing along its surface (along with its ribbed dentricles) to keep its skin clean” [63]. This trait does not transfer to Sharklet because Sharklet does not use water, or any other medium in its environment, to keep itself clean; instead, it prevents bacteria from forming colonies through the use of physical barriers. Ultimately, Wadia’s [63] results prove consistent with the findings presented in the GDG analysis above.

10.6 CONCLUSION

The data and analysis for the GDG study is presented above. Ultimately, the study uncovered preliminary trends in a pool of nine sustainable BIDs. These designs were found to frequently meet a number of efficiency-related GDGs, compared to a functionally equivalent non-BID product. The results of this study were validated through the use of two raters, along with partial validation from the results of related studies.

129 Chapter 11: Additional Keyword Trends

Chapter 11 presents a keyword study uncovering trends in the sustainable BIDs discussed in Chapter 10. First, the methodology is presented, along with an in-depth analysis of three keywords identified – passive mechanisms, multifunctional designs, and optimized geometries. Each keyword is defined in the context of both biology and engineering, examples are provided, and the keyword’s connection to a potential reduction in environmental impact explained. Second, the classification of these three keywords as true ‘trends’ in sustainable BIDs is validated by analyzing the 9 sustainable designs discussed in Chapter 10 and by confirming these trends with other BID literature.

11.1 METHODOLOGY OF KEYWORD TRENDS STUDY

While conducting the study outlined in Chapter 9 and collecting the data summarized in Chapter 10, keywords related to sustainability characteristics of the BIDs repeatedly arose in the literature. These keywords were researched further to see if the concepts they referenced point to a meaningful set of design characteristics desirable in sustainable design and might be accurately applied to the other sustainable BIDs. Each keyword trait was defined using a wide range of literature from biology and engineering, with numerous examples of the keyword traits provided. Literature research was conducted to confirm that the keyword traits are associated with likely sustainability benefits, and that they are likely to be found in biology and BIDs. Using this information, each of the 9 sustainable BIDs was analyzed for the keywords that repeatedly arose in the study, to see if they could be regarded as possessing the trait of interest, even if no sources in the literature directly described them as possessing those traits. Like in Chapter 10, this analysis was conducted by two independent researchers and the results compared. The literature research and results of the analysis are provided below.

130 11.2 IDENTIFYING KEYWORDS

The keywords were identified in the literature on the 9 BIDs analyzed in Chapter 10. For instance, 4 out of 9 sustainable BIDs are described as “passive,” indicating that passive mechanisms may be linked to sustainable BID. Five sources [292,293,295-297] describe Biolytix as “passive”, along with four sources [29-32] for the cooling system in Eastgate Centre, one source [266] for Sharklet, and one source [298] describing self- correction boxfish.

Ultimately, three keywords were identified from the group of sustainable BIDs: passive mechanisms, multifunctional designs, and optimized geometries. Each of these terms was found in the literature on one or more of the designs and the related sustainability characteristic was found to apply to many of the sustainable BIDs analyzed. These three features will be discussed in detail throughout the remainder of the chapter.

11.3 PASSIVE MECHANISMS

Passive mechanisms are discussed throughout literature in biology and engineering. Definitions and explanations of passive mechanisms from a wide range of sources are provided below:  Okada et al. [299] distinguish active and passive compliance in the shoulder mechanisms of humanoid robots, by explaining that “active compliance is realized by actuators” whereas “passive compliance means mechanical compliance of members.”  Wright et al. [300] examine the regulation of impact forces in heel-toe running

and state that “Active changes may consist of altered muscle stimulations of initial conditions prior to heelstrike” whereas “Passive changes are a mechanical reaction of the system to altered shoe hardness.”

131  In the context of the control of functional capillary density in red muscle, Honig et al. [301] explain that active control would be performed “by vascular smooth muscle,” while passive control is performed “by the rheological properties of microvascular networks.”  Dietschy [302] states, in the context of a discussion of the mechanisms for the intestinal absorption of bile acids, that “Net movement of a given substance across a membrane by a passive mechanism can take place only in the

presence of a favorable electrochemical gradient.”

 In the context of prosthetic hand design, Dechev et al. [303] define passive adaptive grasp as not requiring “sensors or electronic processing” to perform their required function. Based on these definitions, it is clear that active mechanisms involve action to perform the desired effect – mechanical actuators or the stimulation of muscle, for instance – whereas passive mechanisms perform the desired function without the need for active energy – for example, through mechanical compliance or the rheological properties of the environment. These definitions and explanations of passive mechanisms support the more general definition of ‘passive mechanisms’ adopted here. Here, passive mechanisms are defined as mechanisms that use ambient energy and perpetually-existing forces, such as gravity, to perform functions. Their system inputs are either renewable, such as waste heat and sunlight, or are not consumed during the operation of the mechanism, such as gravity and magnetic properties. Other potential inputs to passive systems include chemical attraction and repulsion, inertia, and the physics of fluid flow, for instance.

132 11.3.1 Examples of Passive Mechanisms

Passive mechanisms are found in numerous non-bioinspired engineering designs, BIDs, and biological systems. A list of examples described as “passive” in academic literature is provided in the table below with sources. These examples illustrate the potentially wide scope of passive mechanisms within engineering, BID, and biology.

Table 11: Examples of passive mechanisms in non-BID engineered systems, BIDs, and biological systems.

Engineered Systems BIDs Biological Systems (not Bioinspired) 1. Use of v-shaped wall 1. Passive cooling in Eastgate 1. “Passive self-correction of a protrusions to reduce Centre [29-32] body position in the boxfish” turbulence in channel flow 2. “[P]assive transport of solids [298] [304] by waste water” [295 ]; “on- 2. Muscle actuation in animals 2. Passive tuned mass dampers site passive treatment” of can be performed using to reduce vibrations in waste water [297 ]; “passive passive mechanisms in the buildings [305] discharge of raw effluent” hinges between joints [68] 3. “[P]assive elastomeric engine [292 ]; and “Passive 3. Passive soft tissue is present mounts… for isolating an ventilation” [296 ] in in the subtalar and talo- airframe from an engine” Biolytix crural joints in humans [300] [306] 3. Sharklet’s “passive and 4. Passive mechanisms in the 4. Multicomponent phase nontoxic surface” [266 ] wings of fruit flies allow change materials used for 4. Bipedal robots with passive elastic energy storage [315] “passive solar heating” [307] walking mechanisms 5. Stretching soft tissues in 5. “Passive ventilation and [311,312] humans’ hips creates passive heating in a multi-storey 5. Micro-air vehicles with moments [316] structure, by natural passive joints inspired by 6. Passive mechanisms convection” [308] seagulls [313] contribute to functional 6. “Passive solar water-heating” 6. Passive systems to collect capillary density [301] systems [309] and distribute water inspired 7. “[P]assive mechanisms drive 7. Passive solar lighting systems by thorny devils [314] secretory granule for residential or commercial 7. Passive compliance in the biogenesis” in the parasite structures using optical fibers shoulder mechanisms of Giardia lamblia” [317] [310] humanoid robots [299] 8. Passive mechanisms cause 8. “[C]ircuts that provide 8. Passive adaptive grasp in “ionic diffusion of bile lossless passive soft prosthetic hand design [303] acid… across the small switching” [310] intestine” [302] 9. The buildup of calcium salts in human arteries can occur passively [318] 10. “Passive mechanical forces” are involved in caterpillar motion [319]

133 11.3.2 Potential Environmental Benefits of Passive Mechanisms

Passive mechanisms use freely-available, clean, renewable energy. They consequently are connected to a reduction in the consumption of active energy sources, such as fossil fuels. In some sense, passive mechanisms can also be connected to energy efficiency. While the technical energy efficiency of a passive mechanism may be low, because they may use a significant amount of ambient energy, passive mechanisms can still be considered ‘efficient’ from an environmental standpoint because they require fewer active energy inputs to achieve the same outputs as competing products. Many sources discuss the connection between passive mechanisms and energy efficiency, making it clear that this interpretation of energy efficiency is not at odds with the rest of the field. Three sources discuss passive mechanisms that allow energy storage in the wings of fruit flies [315], in compliant members in humanoid robots [299], and in the hips and ankles of humans [316]. This energy storage capability leads to significant increases in energy efficiency, accounting for 10% of the inertial power in the wings of fruit flies [315] and 35% of the net hip moment in humans [316], for instance. Additionally, passive mechanisms in connectors for metamorphic robots have low or no power consumption [320], and wall protrusions have been shown to reduce turbulence in channel flow passively, resulting in as much as a 10% drag reduction compared to a smooth surface [304]. Hence, designs containing a bioinspired passive mechanism are likely to outperform competitors without a passive mechanism when compared using the following GDGs: #1: “Specifying renewable and abundant resources”; #11: “Specifying the cleanest source of energy”; and #32: “Interconnecting available flows of energy and materials within the product or between the product and its environment” [61]. When a reduction in energy inputs to achieve the same outputs is considered energy efficiency, as 134 explained above, GDG #28: “Specifying the best-in-class energy efficiency components” [61] should also be included in this list.

11.3.3 Passive Mechanisms Conclusion

Passive mechanisms perform functions with the use of clean, renewable, ambient energy sources and can be found in a wide range of biological systems, BIDs, and non- BID engineering designs. Passive mechanisms are associated with a number of environmental benefits related to using renewable, abundant, and clean energy; they are often also associated with increased energy efficiency because they require the use of fewer active energy inputs.

11.4 MULTIFUNCTIONAL DESIGNS

Multifunctional components perform numerous functions. For instance, “[m]ultifunctional materials are integrated systems that serve multiple roles such as structural load bearing, thermal management” and energy absorption [321]. Component integration is one way to design multifunctional parts. Component integration is a “design-for-manufacturing (DFM) strategy” that minimizes the total number of parts, frequently producing complex parts [322]. Multifunctional designs are a type of integral product architecture, where “a single chunk implements many functional elements” [322]. Many sources [323-326] emphasize the connection between multifunctionality and integral product architectures, stating that products with integral architectures have many functions performed by one or a few physical parts. In contrast to integral and multifunctional designs, modular architectures have a one-to-one correspondence between functions performed and physical elements [322,324,326,327].

135 11.4.1 Examples of Multifunctional Designs

Many non-BID engineering designs, BIDs, and biological systems are described in academic literature as “multifunctional.” A number of examples are provided in the table below. Designs described as “integrated” or “integral” that appeared to multifunctional were also included. These examples show the broad scope that multifunctional designs have.

Table 12: Examples of multifunctional designs in non-BID engineered systems, BIDs, and biological systems.

Engineered Systems BIDs Biological Systems (not Bioinspired) 1. The physical structure for the 1. Liu and Jiang [328] 1. Liu and Jiang [328] provide a list transmission of the BMW provide a list of 13 of 17 multifunctional materials R1100RS motorcycle bioinspired in biological organisms: butterfly provides both structural multifunctional materials wings, brittlestars, cicada wings, support and power with sources and a list of fish scales, gecko feet, lotus conversion [322] their multifunctional leaves, mosquito compound 2. Integrated into “the throttle- properties, including eyes, nacre, peacock feathers, body end of [a] redesigned fabrics, glass, glass slide, polar bear fur, rice leaves, rose intake manifold” “are the nickel, PAH- petal, shark skin, spicule, spider attachments for the EGR SPEEK/PAA, PDMS, capture silk, spider dragline silk, return and the vacuum source PUA, Si wafer, silica, and water strider legs. block. These attachments use silicon, UPy, and ZnO. 2. “A striking particularity of nastic a molded ‘push in and turn’ 2. “The Eastgate Complex structures is an efficient and geometry, eliminating the integrates the internal inconspicuous design that need for several threaded and external integrates two or more fasteners” [322] environments reducing functions… into one smoothly 3. Stone et al. [324] name the chances of system operating unit” [329 ] wrenches and screwdrivers as failure” [63] 3. The “natural fibrous composite examples of integral material” in the “cuticle of products, stating that “[a]ll arthropods” is “multifunctional” functions are embodied by [11 ] one physical element.” 4. The shark’s dermal denticles are 4. A drawer with an indentation multifunctional because they to accommodate a hand is an both reduce drag and keep the example of an integrated skin clean” [31] design because it eliminates 5. Pandremenos et al. [330] discuss the need for a separate handle a number of integrated and and fasteners [325] multifunctional designs including the “highly integrated modules” in “the metabolic network of various organisms” and honeycomb.

136 11.4.2 Potential Environmental Benefits of Multifunctional Designs

Because they are a subset of integral designs, multifunctional designs share the same environmental benefits. Integral designs are linked to materials efficiency for a number of reasons. First, they frequently eliminate redundant parts; for example, a redesigned intake manifold “eliminat[ed] the need for several fasteners” through the integration of “the attachments for the EGR return and the vacuum source block” [322]. Additionally, the function- sharing in integral designs reduces materials usage, and “the geometric nesting of components” minimizes the volume [322], which is why other authors describe integral products as “lightweight” and “compact” [330]. For example, the integral architecture of the BMW R1100RS motorcycle, a non-BID engineered product, helped reduce the mass and volume of the design [322]. Integral designs are loosely connected to energy efficiency as well. The material efficiency of integral designs, discussed above, translates to a reduction in the mass, and a reduction in energy required during transportation and operation. Additionally, products with integral architectures are linked to a higher degree of optimization than modular products [322,331], particularly with respect to performance characteristics, such as “acceleration, energy consumption, aerodynamic drag” and noise that are “driven by the size, shape, and mass of a product” [322]. As a result of their environmental benefits, multifunctional and integral designs are likely to meet the following GDGs better than a modular comparison product: #16,

#17, #18, #21, #27, #28, #40, #52, and #59. GDGs #21: “Minimizing the number of components”; #52: “Minimizing the # and variety of joining elements”; and #59: “Condensing into a minimal # of parts” [61] are all related to reducing the number of redundant parts. GDGs #16: “Employing folding, nesting or disassembly to distribute 137 products in a compact state”; #17: “Applying structural techniques and materials to minimize the total volume of material”; #18: “Specifying lightweight materials and components”; and #27: “Minimizing the volume and weight of parts and materials to which energy is transferred” [61] are all associated with minimizing the volume and mass of parts. Additionally, GDG #28: “Specifying best-in-class energy efficiency components” [61] is associated with increased optimization for acceleration, energy consumption, drag, and noise.

11.4.3 Potential Environmental Benefits of Modular Designs

However, modular product architectures are also associated with environmental impact advantages, primarily during a product’s end-of-life. These advantages include enhanced ability to be maintained [332,333], reconfigured [334], upgraded [332-334], reused [332-335], remanufactured [335], recycled [332-335], and have problems diagnosed and repaired [332]. For example, “the fact that the alternator is a separate module that can be removed fairly easily (as opposed to being an integral part of the engine block) aids in both service and in product retirement” [327]. Hence, modular designs are likely to meet the following GDGs better than a multifunctional or integral comparison product: #38, #39, #55, #57, and #58. GDG #38: “Reutilizing high-embedded energy components” [61] is related to the increased reusability of different modules. GDG #39: “Planning for on-going efficiency improvements” [61] is related to increased upgradability. GDG #55: “Ensuring that incompatible materials are easily separated” [61] is related to increased recyclability.

GDGs #57: “Organizing in hierarchical modules by aesthetic, repair, and end-of-life protocol” involves how a product is grouped in modules, and #58: “Implementing

138 reusable/swappable platforms, modules, and components” [61] is directly related to the existence of modules.

11.4.4 Multifunctional Design Conclusion

Multifunctional designs perform functions with fewer overall components and less material than modular designs. They can be found in a wide range of biological systems, BIDs, and non-BID engineering designs. There are many environmental tradeoffs between modular and integral/multifunctional designs, and the decision of which type of design to use depends on the specifics of the type of product and its intended application. Integral, and hence multifunctional, designs are associated with materials efficiency because they eliminate redundant parts, minimize the mass of parts, and minimize the volume of parts through nesting. They are also associated with energy efficiency because of their reduced mass and the fact that they are more likely to be optimized for energy-related parameters. In contrast, modular designs are associated with environmental benefits in end-of-life; they can be more easily maintained, repaired, reused, and recycled, for instance.

11.5 OPTIMIZED GEOMETRIES

‘Optimized geometries’ are shapes that are particularly desirable, for example, because they are aerodynamic, resistant to deformation, prevent organisms from growing on their surface, or encourage desirable fluid flow for heat transfer or acoustics. There is some theoretical support indicating optimized geometries are likely to successfully transfer their benefits to engineering designs because geometry is a surface-level attribute, making it easier to replicate in engineering [80].

139 11.5.1 Examples of Optimized Geometries

Many non-bioinspired engineering designs, BIDs, and biological organisms reportedly have optimized geometries. A list of examples explicitly referenced in academic literature is provided in the table below. These examples illustrate the scope of optimized geometries within engineering, BID, and biology.

Table 13: Examples of optimized geometries in non-BID engineered systems, BIDs, and biological systems.

Engineered Systems BIDs Biological Systems (not Bioinspired) 1. “Fiber-optic SERS sensor 1. The surface of some earth-moving 1. “One of the most with optimized geometry” machinery (ploughs) was inspired intriguing shapes is the [336] by the geometrically optimized branching structure of 2. “A two-dimensional ridges on soil-moving animals [11] the “adhesive” hairs on lightweight cantilever 2. Optimized geometries are in the the foot of the gecko. structure… comprising 40 bionic concept car, and the They are far finer than rigidly joined beams, of Shinkansen’s nose cone and anything generated by which the geometry is pantograph [63]. etching processes, being optimized to reduce 3. In an organ on a chip, “[t]he of nanometric vibration transmission over geometry of [the]engineered tissue dimension at the a given bandwidth” [337] interface was optimized to tipmost branches” [294] 3. Optimizing the geometry of approximate the blood flow rate of 2. “The optimally located the chamber in the liver and to align rat holes in the insect microchannel reactors hepatocytes… as they do along the cuticle deform under promotes flow uniformity endothelium-lined sinusoidal barrier external stimuli” [63] [338] in vivo” [343] 3. “The microscopic ribs 4. Optimizing blade 4. “[M]oth-eye anti-reflection of the shark’s scales geometries for transonic coatings” where “[t]he geometry of suppress turbulence in compressors using CFD closely packed arrays of nanoripples the boundary-layer [339] was optimized for operation” in flow,” reducing energy 5. Optimized gas nozzle solar cells [344] loss caused by drag [68] geometries [340] 5. Using the performance of Ensis 4. “Adaptive geometry of 6. Topology optimization for directus, the Atlantic razor clam, burrow spacing in two scaffolds in bone tissue “and the animal’s geometry” Winter pocket gopher engineering [341] et al. [345] “calculated that an populations” [347] 7. Optimized geometries for Ensis-based burrowing/anchoring 5. Andersen [348] vascular stents [342] system would provide a 10X discusses the adaptive improvement.” geometry of geomyid 6. “[O]ptimum bio-inspired attachment burrows in the context structures” based on the of different “[s]tructure, size, and shape of environmental contact elements” in “insects, constraints related to spiders, and geckos” are being energetics. developed [346].

140 11.5.2 Potential Environmental Benefits of Optimized Geometries

Ultimately, whether an optimized geometry confers a sustainability-related benefit depends on the sense in which the geometry is optimal. If a profile on a BID is optimized to more easily get the attention of consumers, for instance, this would not be expected to confer a sustainability-related advantage. In some cases, however, optimized geometries are likely to cause a system to be more energy efficient. For instance, “The microscopic ribs of the shark’s scales suppress turbulence in the boundary-layer flow,” reducing energy loss caused by drag [68]. Frequently, when bioinspired optimized geometries are incorporated into products, only minor changes to the existing geometrical profile of products are required. Unless these slight changes in geometry require different manufacturing process or materials to be used, it seems that incorporating optimized geometries would likely have a very small impact in other stages of the life cycle. Consequently, it is likely that incorporating an optimized geometry would lead to a more sustainable product overall.

In addition, the models of biological systems used by engineers in BID may frequently be more ‘optimized’ and ‘efficient’ than the biological organism they are modeling. Weber et al. [224] observed that models of biological systems are frequently idealized, and when they compared the performance of real and idealized versions of cetacean flippers in water tunnel testing, they found that “[d]rag performance was significantly improved by idealization.” Hence, if a final design is more likely to be efficient when it has been inspired by an efficient analogy, engineers conducting BID may see this advantage simply by modeling and idealizing the biological system. Because of the wide range of ways geometries could be optimized, and the consequent range of environmental impact advantages they could have, optimized geometries are not analyzed here in terms of the GDGs they are likely to affect. 141 11.5.3 Optimized Geometries Conclusion

Optimized geometries perform a wide range of functions as a result of their desirable shape. In some cases, optimized geometries are likely to cause a system to be more energy efficient. Minor changes in shape to optimize geometries found in products would likely have a very small environmental impact in other stages of the life cycle. Hence, incorporating an optimized geometry into a design would likely lead to a more sustainable product overall.

11.6 VALIDATION OF KEYWORD TRENDS BY ANALYZING 9 SUSTAINABLE BIDS

Two researchers analyzed the nine sustainable BIDs using the same procedure discussed in Chapter 10 to see which contained bioinspired passive mechanisms, multifunctional designs, and optimized geometries, and experienced an environmental impact advantage over their competitors as a result of these bioinspired features. A summary of these results is show in the table below. An explanation of why each design was found to have these traits is provided in Appendix H.

Table 14: Keyword trends found in sustainable BIDS.

Passive Multifunctional Optimized Bioinspired Designs Analyzed Mechanisms Designs Geometries Biolytix Filter X Daimler-Chrysler Bionic Car - Shape X Daimler-Chrysler Bionic Car - Structure Eastgate Centre Cooling System X X Interface FLOR i2 Entropy Carpet Self-Cleaning Transparent Thin Film X X Sharklet Antimicrobial Surface X Shinkansen 500 Series Nose Cone X Shinkansen 500 Series Pantograph X

As is shown in the table above, 3 of the 9 BIDs were found to have bioinspired passive mechanisms that conferred an environmental impact advantage. To be considered 142 as such, the biological analogy needed to have a passive feature that was then transferred to engineering and remained passive in the BID. Additionally, they needed to have a feasible ‘active’ alternative design in engineering. All 3 BIDs with bioinspired passive mechanisms met many of the GDGs connected to passive mechanisms better than the competing product; all three met GDGs #1 and #32, and two of the three met GDG #11. Two of the 9 sustainable BIDs were identified as being more multifunctional than competing products as a result of their bioinspired features. BIDs were classified as

‘multifunctional’ only if the BID integrated two components that were separate in the competing product, but were integrated in the biological analogy. Additionally, the component integration needed to be the cause of the reduced environmental impact. Of the ten GDGs theoretically associated with integral and multifunctional designs, GDGs #17, #18, #27, #28, #40 are hit by the 9 BIDs analyzed in the study. The two BIDs determined to be multifunctional designs hit at least one of these guidelines. With the exception of Inteface FLOR, which met guideline #58, none of the other BIDs met any of the GDGs associated with modularity. Four out of ten of the designs analyzed in the study had optimized geometries that were transferred from the biological analogy to the engineered design and conferred a sustainability advantage.

11.6.1 How This Analysis Validates the Three Keyword Trends

This analysis is fundamentally different than the methodology that drove the discovery of the keywords. Rather than looking in the BID literature for quotations related to these terms for each of the designs, the designs were analyzed using the information from the library entries and the definitions of the keywords, provided above, to see whether or not the designs had each of the potential keyword trends. In many

143 cases, this meant that designs with no reference in the literature to the keywords were determined to have one of the keyword trends; for instance, no quotations were found describing the self-cleaning transparent thin film as passive, but it was still found to have a passive mechanism in the analysis. In other cases, designs with a reference in the literature to one of the keywords were ultimately found to not have the related keyword trend; for instance, self-correction boxfish was described as passive in the literature [298], but the shape of the Daimler-Chrysler concept car was not found to have a passive mechanism. Hence, this analysis is different from the methodology that originally developed the list of keyword and can be used to confirm that passive mechanisms, multifunctional designs, and optimized geometries are trends in sustainable BID. However, since the keywords were frequently found in the literature on these designs it is more likely that this particular sample of sustainable BIDs would possess these features, meaning further support is necessary.

11.7 VALIDATION OF TRENDS USING BID LITERATURE

Other sources in BID literature focused on finding design principles in biology or biomimetic design principles further confirm that the three keywords identified represent true trends in sustainable BIDs. In particular, a 2010 conference paper from Wadia and McAdams on biomimetic guidelines [62], a 2011 thesis from Wadia on biomimetic design principles [63], a 2009 figure from the Biomimicry Guild on life’s principles [64], and a 2011 figure from the Biomimicry Group, also on life’s principles [65], are heavily used. More information on these sources can be found in Chapter 2.

11.7.1 Passive Mechanisms

Three of the sources mentioned above present principles related to passive mechanisms. Both the Biomimicry Guild and the Biomimicry Group documents deal 144 with the design principles of biology and have the analogous principles: “free energy” [64] and “use readily available materials and energy” [65], respectively. The Biomimicry Group also describes the “Operating Conditions” in biology as including “sunlight, water, and gravity” [65]. These two sources imply that many passive mechanisms in biology should exist, at least at the initial places on the food chain where this free, readily available energy from the sun is harnessed. In addition, work confirms that BID can be used to design products with passive mechanisms. One of Wadia’s [63] biomimetic design principles – “Use materials and/or energy from the environment to help the product/system accomplish its function” – is of a similar nature, but is related directly to BIDs. Hence, the results presented above from the keyword trends study regarding passive mechanisms are consistent with, and validated by, the work from Wadia [63], who used a different methodology on a pool of standard BIDs to arrive at the same trend; this work is also consistent with efforts from the Biomimicry Guild and Biomimicry

Group, whose methodology is far less transparent, but is likely to be substantially different from the methodology presented here.

11.7.2 Multifunctional Designs

Many sources confirm the presence of multifunctional designs in biology. The Biomimicry Group [65] includes three principles related to multifunctional design: (1) “integrate the unexpected”; (2) “use multi-functional design” under the category “be resource (material and energy) efficient”; and (3) “combine modular and nested components” under the category “integrate development with growth.” Similarly, the Biomimicry Guild [64] lists “multi-functional design” as one of ‘Life’s Principles.’ Additionally, Pandremenos et al. [330] study a number of examples of both modular and

145 integral design architectures in biology, finding that integral architecture is common in “cases where… strong relations among the different parts are required” “for the biological systems to function properly.” Both Pandremenos et al. [330] and Liu and Jiang [328] claim that biological materials are multifunctional. Helms et al. state: “Biological designs typically result in more multi-functional and interdependent designs than engineering designs” [144]. Additionally, work from Wadia [63] and Wadia and McAdams [62] confirm that

BID can be used to create multifunctional designs in their similar biomimetic design principle and biomimetic design guideline – “Make a single part from two or more parts with distinctive material properties and functionalities” and “incorporate multifunctionality,” respectively. Wadia and McAdams [62] observed this biomimetic design guideline in 40% of the 20 BIDs they analyzed.

11.7.3 Optimized Geometries

Both the Biomimicry Group [65] and Biomimicry Guild [64] confirm the presence of optimized geometries in biology, through the principle: “fit form to function,” which is under the category “be resource (material and energy) efficient” in the Biomimicry Group’s version. Additionally, both Wadia and McAdams [62] and Wadia [63] confirm the ability of BID to generate optimized geometries. Wadia and McAdams [62] observed instances of “Fit form to function” in 50% of the BIDs they analyzed, and Wadia’s [63] biomimetic design principles include - “Form: Adapt and optimize the form/shape/size of the product to meet specific functional needs.” All of this work serves to validate the idea that ‘optimized geometries’ are a true trend in BIDs.

146 11.8 CONCLUSION

Three keywords were identified from the literature on the 9 BIDs analyzed in Chapter 10 – passive mechanisms, multifunctional designs, and optimized geometries. Each of these concepts was defined, and numerous examples of these types of designs in non-BID engineering, BID, and biology were provided. The relation between each design type and potential environmental impact reductions were discussed. In particular, all three design types are associated with either energy or materials efficiency.

To determine whether these keyword design types represent true trends in sustainable BIDs, the pool of 9 BIDs was then analyzed to see whether they actually contained bioinspired features of these types, and to see whether these features were associated with environmental benefits. Of 9 designs analyzed, 3 had passive mechanisms, 2 were multifunctional, and 4 had optimized geometries. Because the methodology used to determine the keywords is different from that used to determine whether these design types are truly present in the BIDs, this analysis partially confirms that these three design types represent trends in sustainable BIDs. Additionally, work from the BID community enumerating biology’s design principles and general biomimetic design principles further confirm the results presented here. Hence, there is evidence that passive mechanisms, multifunctional designs, and optimized geometries are true trends in sustainable BIDs.

147 Chapter 12: Section 2 Conclusion

Chapter 12 concludes Section 2, which identified and analyzed trends related to environmental impact reduction in existing sustainable BIDs. A summary of Section 2 is provided, followed by a brief discussion of the challenges encountered when conducting the studies. This chapter concludes with a discussion of opportunities for future work, including the types of analysis that could be done if more sustainable BIDs were analyzed and the potential design tools and methodologies that could be developed.

12.1 SUMMARY OF SECTION 2

Chapter 9 presented a methodology for developing a comprehensive list of BIDs, determining which designs have an environmental impact advantage as a result of their bioinspired features, and identifying sustainability-related trends in these designs using GDGs. Extensive information from academic sources was compiled in ‘design library’ entries in Appendices A-C for 15 designs, 9 of which were shown to have sufficient information and a true environmental impact advantage. Chapter 10 discussed the results of the GDG analysis for the 9 designs, showing the types of trends that may arise in the population of sustainable BIDs. A summary of the GDGs most frequently met better by the sustainable BIDs than competing products is provided in the table below. Two of the four GDGs – #1 and #9 – are related to materials selection, using renewable and abundant materials and using clean materials, respectively; the other two GDGs – # 28 and #32 – are related to efficiency advantages.

148 Table 15: Summary of the GDGs most frequently met better by the 9 sustainable BIDs.

Frequency GDG (from Telenko [61]) 3 GDG #1: Specifying renewable and abundant resources 3 GDG #9: Specifying non-hazardous and otherwise environmentally "clean" substances, especially in regards to user health 7 GDG #28:Specifying best-in-class energy efficiency components 3 GDG #32: Interconnecting available flows of energy and materials within the product or between the product and its environment

In Chapter 11, passive mechanisms, multifunctional designs, and optimized geometries were identified as recurring keywords in the pool of 9 sustainable BIDs related to environmental impact. These keywords were defined, and their connection to reduced environmental impact – particularly energy and materials efficiency – was explained. Finally, these keywords were validated and shown to truly represent trends in sustainable BIDs. A summary of the results from the keyword trends analysis using the 9 sustainable BIDs is provided in the table below.

Table 16: Summary of the keyword trends found in the 9 sustainable BIDs.

Frequency Keyword Trend 3 Passive Mechanisms 2 Multifunctional Designs 4 Optimized Geometries

The results of Section 2 indicate that sustainability-related characteristics from biology are able to be transferred to engineering, and are currently being transferred via BID. Hence, it is possible to develop tools and methodologies directed toward using BID for sustainable engineering design. For all sustainability-related traits, there may be tradeoffs in other life cycle stages which should be considered before incorporating them into a product.

149 12.2 CHALLENGES ENCOUNTERED

The process of compiling the information necessary for each of the 9 designs from academic sources was challenging. Limited reliable information was available for each BID; numerous sources were needed for each design to verify, qualify, and add to the information found in the initial source from the breadth and depth searches. It was especially difficult because implemented bioinspired products with a plausible sustainability advantage are rare. Frequently, a reference to a BID found in the depth and breadth searches was a reference to an idea for a BID, not a reference to an actual product or constructed system; many sources offer one-sentence ideas for BIDs, without any discussion of what it would take to manufacture, build, use, and dispose of this system. Additionally, few designs had evidence of a sustainability advantage, fewer still had evidence of a sustainability advantage as a result of their bioinspired feature, and almost none had evidence of a sustainability advantage as a result of their bioinspired feature in peer-reviewed academic literature. It is for these reasons that few designs were analyzed.

12.3 FUTURE WORK

Many avenues exist for future work related to the studies presented in Section 2, including analyzing more sustainable BIDs, developing sustainable BID tools and methodologies, and identifying potential advantages of BID over alternative design-by- analogy techniques.

12.3.1 Analyzing More Sustainable BIDs

Both studies presented in Section 2 would be greatly enhanced by analyzing more sustainable BIDs. First, the keyword trends study would benefit because additional keywords related to sustainability-characteristics could be identified, and the existing keyword trends – passive mechanisms, integral and multifunctional designs, and

150 optimized geometries – could be more thoroughly verified in the population of sustainable BIDs. Second, including more BIDs in the GDG analysis would clarify the trends and would allow for a more sophisticated analysis. A larger pool of sustainable BIDs would confirm or refute the tendency towards efficiency-related GDGs observed in the 9 sustainable BIDs. Additionally, BIDs could be divided into categories based on field (architecture, chemical engineering), type of bioinspired feature (surface topology, behavior, energy conversion process), the presence of particular bioinspired traits

(passive mechanisms, optimized geometries), the scale of the analogy (macro scale vs. nano scale), the product life cycle phase where the bioinspired sustainability benefit exists (use, end-of-life), etc. to identify more sophisticated and accurate trends. Additionally, analyzing more designs would allow researchers to examine whether some GDGs cannot be met through BID, or are not being met through BID. For instance, a number of GDGs concern the designer or user, such as GDG #43: “Indicating on the product which parts are to be cleaned/maintained in a specific way” [61]. As biology does not have a conscious user who needs instructions, sustainability solutions to better meet this guideline are unlikely to be uncovered through BID. Likewise, easy disassembly is typically not a valuable characteristic for organisms, as organisms typically benefit from having all body parts attached and intact, making it unlikely that sustainability solutions for GDGs like #62: “Specifying all joints so that they are separable by hand or only a few, simple tools” [61] would be found using BID. Hence, a greater number of analyzed sustainable BIDs would allow researchers to better understand the GDGs that are and are not likely to be met using BID.

151 12.3.2 Developing Tools and Methodologies for Sustainable BID

The results of both studies in Section 2 could also serve as a foundation for developing design tools and methodologies related to sustainable BID. For instance, the summary of the GDG Analysis results, in Appendix G, could be used by engineers to find examples of products that are able to meet particular GDGs. For instance, if an engineer wanted to reduce energy consumption to better meet GDG #1, he or she could research the BIDs that met this guideline – the Biolytix BioWater filter,

Eastgate Centre, and the self-cleaning surface inspired by the lotus leaf, as shown in the figure below – and use these designs and their biological analogies as analogies.

Figure 21: Depiction of a potential design tool that could be used to find examples of sustainable BIDs that meet a particular GDG. Photo credit: [35,44,349].

Additionally, a number of potential design tools and methodologies could originate from the keyword trends study. First, a checklist for designers could be created that explains and provides examples of each keyword trend. Somewhat like the GDGs,

152 this checklist would make designers aware of potential sustainability-related traits they could incorporate in their designs, such as passive mechanisms. Second, methodologies could be developed to help engineers generate designs with the keyword traits. For example, methodologies could be developed to assist in part integration and the development of multifunctional designs.

12.3.3 Identifying Potential Benefits of BID over Other Design-by-Analogy Techniques

Finally, researchers could determine whether BID is more likely to generate designs with a specific keyword trait than other design-by-analogy techniques, by comparing the frequency of these traits in biology and in the population of alternate analogies. Assume, for instance, that a designer wants to consider concepts with passive mechanisms, and that 40% of all biological organisms contain a passive mechanism while only 5% of all engineered designs do. It would then be advantageous to use biological organisms rather than patents as analogies, due to the increased likelihood of finding passive mechanisms in the pool of potential analogies. By comparing the rates of these sustainability-related traits in different pools of potential analogies, sustainability- related advantages of different analogy types can be uncovered.

12.4 CONCLUSION

Three main topics were discussed in Chapter 12. First, the results of Section 2 were summarized, establishing that biological analogies are being used by designers to make more sustainable engineering products and that many of these bioinspired environmental benefits are related to efficiency. Second, the challenges encountered while identifying and collecting information on the sustainable BIDs were discussed, particularly the difficulty in identifying sustainable bioinspired features and the time

153 associated with collecting all necessary information from reputable sources. Finally, a number of avenues for future work were presented, including analyzing more sustainable BIDs to allow for increased robustness of the results, developing tools and methodologies for sustainable BID, and identifying potential benefits of BID over other design-by- analogy techniques by examining the rates of sustainability traits in different pools of potential analogies.

154 Chapter 13: Thesis Conclusion

Chapter 13 concludes the thesis and is broken into three sections. First, a brief summary of the thesis is presentede, followed by a summary of the thesis contributions. Finally, future work related to the research presented in both Sections 1 and 2 together is provided.

13.1 SUMMARY OF THESIS

Chapters 1 and 2 serve as an introduction to the thesis. Chapter 1 introduces the topic and explains the organization of the thesis, while Chapter 2 discusses the fundamentals of understanding and measuring environmental impact, as well as previous work related to design principles found in biology and BIDs. Chapters 3-8 are grouped into Section 1, which examines the claimed benefits of BID using literature from biology and engineering design. Chapter 3 presents the methodology of this study. Chapters 4, 5, 6, and 7 examine, respectively, claims related to ideation, optimization in biology, sustainability in biology, and features of the BIDs themselves. Chapter 8 concludes the section, discussing claims that were not selected for analysis, issues that arose regarding what constitutes a biological analogy, and future work. Chapters 9-12 are grouped into Section 2, which identifies trends in existing sustainable BIDs. Chapter 9 presents the methodology for a study comparing sustainable BIDs and their competitors using GDGs, and Chapter 10 discusses the results of the study for 9 sustainable BIDs. Chapter 11 delves deeper into the information collected on the

BIDs, identifying sustainability-related trends using keywords that frequently arose in the literature on the sustainable BIDs. Chapter 12 concludes Section 2, discussing the difficulty in collecting sufficient information for the sustainable BIDs, the potential

155 benefits of analyzing more sustainable BIDs using the methodologies presented in the section, potential design tools and methodologies that could be developed related to sustainable BID, and ways in which an extension of the keyword trends study could help identify potential benefits of BID over other design-by-analogy techniques.

13.2 DISCUSSION OF THESIS

The central theme of this thesis is two-fold. On one hand, it appears that many of the claimed benefits of BID, including those related to sustainability in both biology and engineering, are invalid. On the other hand, it appears that bioinspired features have and do regularly confer sustainability-related benefits to designs and that there is significant potential to use biological analogies in sustainable design. Section 1 showed that there is still much work to be done concerning the fundamental theory of BID, related to its unique capabilities and advantages over other design methodologies, including other design-by-analogy techniques. There is substantial confusion and disagreement related to the benefits of BID, and many of the oft-cited reasons for conducting BID prove invalid in light of academic work from engineering design and biology. Additionally, it is clear that the vast majority of accounts of these benefits – provided in academic books, conference papers and journals – are not sufficiently rigorous to avoid unintentionally misrepresenting fundamental tenants of biology or engineering design. Whatever future theories of BID are developed must be firmly grounded in an advanced understanding of both engineering design methodology and biology.

Within the design theory and methodology research community, it is popular to study and focus on the novelty-related benefits of BID in ideation. Consequently, these benefits are well-documented, as was shown in Chapter 4, and most existing BID

156 methodologies are focused on promoting these benefits – choosing appropriately- distanced biological analogies, maintaining relevance to the design problem, and avoiding design fixation. Preliminary efforts in the BID community to conduct research related to sustainable BID served to dispel the myth ‘All BIDs are sustainable,’ with the possible unfortunate consequence of directing research efforts elsewhere. However, there is potential to learn environmental impact reducing techniques from biological organisms, as was shown theoretically in Chapter 6 and empirically in

Section 2. Section 2 provided examples of the types of sustainability advantages that can be achieved using BID – both related to the GDGs they are likely to meet and the types of bioinspired sustainability-related traits that are likely to cause their environmental impact reductions. While the data used to arrive at the conclusions presented in Chapters 10 and 11 is limited, as only 9 sustainable BIDs were analyzed, these chapters show how bioinspired sustainability-related features can be identified. These chapters also suggest that many of the bioinspired sustainability-related advantages are likely to be related to energy and materials efficiency, and that certain types of biological analogies are likely to confer certain types of benefits, i.e. a modular biological design is more likely to aid designers in meeting GDGs #38, #39, #55, #57, and #58 related to end-of-life advantages, while an integral design is more likely to help designs meet GDGs #16, #17, #18, #21,

#27, #28, #40, #52, and #59 related to materials and energy efficiency. Hence, it is hoped that this work will inspire renewed interest in the development of sustainable BID methodologies. These methodologies will likely begin with a specific environmental impact-related engineering problem: the redesign of a product to better meet a specific GDG, or a more general environmental benefit, such as increased energy efficiency in use. If the desired environmental benefit is related to the types of designs likely to be present in biology, as would be identified through studies such as those 157 presented in Section 2, a BID methodology can then be selected. This BID methodology will likely involve the identification of biological analogies relevant to the problem of interest using existing methods – biological databases and experts. Based on the findings from Section 1, not all biological organisms and systems are likely to have the same environmental impact characteristics of interest. Hence, the pool of potential analogies should be scoped further, to include only those with the type of environmental impact advantage of interest, either using additional software, if possible, or through the use of experts in biology who can determine whether certain organisms have been selected for energy efficiency advantages, for instance. Once these analogies have been selected, methodologies should guide designers to retain these desirable sustainability-related features in the final design: checklists for verifying that the feature is retained in the design, probably in conjunction with existing sustainable design tools, such as GDGs. This transfer process may involve a closer level of mechanism imitation than is traditionally recommended in BID aimed at producing novel designs, since design fixation is less of a concern, and it is critical to maintain the sustainability-related benefits of the feature being imitated in the final design.

13.3 FUTURE WORK

Numerous avenues for future work related to either the theoretical study, presented in Section 1, or the empirical studies, presented in Section 2, were discussed in Chapters 8 and 12, respectively. Here, one particular avenue for future work that combines element from both sections – a theoretical study analyzing the GDGs in the context of biology – is discussed. Theoretically analyzing the GDGs in the context of biology would provide a better understanding of scenarios in which there might be selection pressure in biology

158 for a trait related to each of the GDGs. Work from Chapter 6 analyzing the claims related to specific GDGs, with explanations of when these claims do and do not hold true, could be used as a starting point for this analysis. Table 17 below shows the relevant claims analyzed in Chapter 6 and their analogues in the GDGs. The results from this analysis could be used to clarify when and how biological systems could help designers better meet each of the GDGs. For instance, GDGs #62 “Specifying all joints so that they are separable by hand or only a few, simple tools” [61] is unlikely to frequently be related to sustainable design solutions from biology, but solutions may be found in rare organisms that experience a fitness advantage by having easily detachable body parts, such as lizards whose tails separate from their bodies to increase survival in certain interactions with predators [350]. Hence, this analysis may make GDGs that are seemingly unrelated to solutions in biology conceptually accessible to engineers and allow a broader range of sustainability solutions to be found using BID. Additionally, this theoretical analysis would more fully address the work begun in

Chapter 6 aimed at explaining the ways in which biology is and is not sustainable. One of the limitations of the work in Section 1 was that only claims frequently made in the literature on BID were available to be analyzed; no consideration was given to potential sustainability-related benefits of biological systems that had not already been identified by other BID authors. The GDGs, intended to capture all the ways in which products can be made more sustainable throughout their life cycle, provide a much more complete framework for understanding how biology is and is not sustainable.

159 Table 17: Claims analyzed in Chapter 6 with related GDGs.

Claim GDG (from Telenko [61]) Biological organisms GDG #1: Specifying renewable and abundant resources use renewable and abundant inputs. Biological materials GDG #9: Specifying non-hazardous and otherwise environmentally are nontoxic. “clean” substances, especially in regards to user health Biological organisms GDG #13:Specifying clean production processes for the product and in employ sustainable selection of components manufacturing GDG #23:Specifying clean, high-efficiency production processes processes. Biological organisms GDG #8: Installing protection against release of pollutants and do not pollute. hazardous substances GDG #9: Specifying non-hazardous and otherwise environmentally “clean” substances, especially in regards to user health GDG #10:Ensuring that wastes are water-based or biodegradable GDG #11:Specifying the cleanest source of energy GDG #26:Implementing fail-safes against heat and material loss Materials in biology GDG #2: Specifying recyclable, or recycled materials, especially those are recycled. within the company or for which a market exists or needs to be stimulated GDG #4: Exploiting unique properties of recycled materials Biology is resistant to GDG #41:Ensuring minimal maintenance and minimizing failure damage. modes in the product and its components GDG #42:Specifying better materials, surface treatments, or structural arrangements to protect products from dirt, corrosion, and wear Biology is efficient. GDG #17:Applying structural techniques and materials to minimize the total volume of material GDG #18:Specifying lightweight materials and components GDG #21:Minimizing the number of components GDG #22:Specifying materials with low-intensity production and agriculture GDG #23:Specifying clean, high-efficiency production processes GDG #25:Implementing reusable supplies or ensuring the maximum usefulness of consumables GDG #26:Implementing fail-safes against heat and material loss GDG #27:Minimizing the volume and weight of parts and materials to which energy is transferred GDG #28:Specifying best-in-class energy efficiency components GDG #31:Maximizing system efficiency for an entire range of real world conditions GDG #32:Interconnecting available flows of energy and materials within the product or between the product and its environment

160 One challenge associated with conducting this theoretical analysis is that the researcher must have a deep and nuanced understanding of evolutionary biology, and must be aware of a wide range of outlier biological organisms and systems. It would likely be very difficult and time consuming for someone without a formal background in biology to conduct such an assessment.

161 Appendix A: Design Library Entries for 9 BIDs That Met All Selection Criteria and Were Analyzed Using GDGs

Information on 9 sustainable BIDs – Biolytix, Daimler-Chrysler Bionic car shape, Daimler-Chrysler Bionic car structure, Eastgate Centre cooling system, Interface Flor Entropy Carpet, self-cleaning transparent thin film, Sharklet antimicrobial surface, Shinkansen 500 series nose cone, and Shinkansen 500 series pantograph – is presented in Appendix A. First, a summary of the basic information is provided, including the competing product and the biological analogy. Second, a description of the biological analogy is provided, followed by a description of the BID, quotations from authoritative sources verifying that the selection criteria have been met, and a comparison of the environmental impact of the BID and its competitor.

162 A.1 BIOLYTIX FILTER

Field Biological Analogy Environmental Advantage Civil Engineering Natural decomposition of debris No chemicals, smaller filtration on a river’s edge system, fewer energy-consuming parts, less maintenance

Company Competitor Life Cycle Phase Biolytix Septic tank Manufacturing and Use

Biological Analogy Description Organic matter decomposes naturally in wet environments, such as those found in riparian zones, “land adjacent to a stream, river, lake, or wetland” [351]. Decomposition occurs more quickly in oxygen-rich environments because the microbes that break down organic matter use oxygen for cellular respiration [352]. As organic matter decomposes in these wet environments, the waste and pollutants are filtered by the riparian zone [353].

Decomposition of plants in a riverbed [354,355].

Bioinspired Design Description Biolytix is a filtration device for households that mimics the filtration and treatment of waste in riparian zones. The Biolytix system filters and treats “raw domestic waste water and solid organic waste” [356], including paper, cloth, sanitary pads, tampons, grass clippings, dust, hair, lint, feces, oil, grease, soap, detergents, and household chemicals [293]. Biolytix converts this waste into “a valuable soil amendment” [293]. As the waste travels down the filtration bed, it decomposes and forms humus. This humus “forms the bulk of the [filtration] bed” and serves as an “active filtration matrix” that filters the wastewater [292].

As in riverbeds, oxygen is required for decomposition. Hence, it is important that the filtration system does not clog, preventing oxygen to penetrate to the bottom of the filtration matrix. As in riverbed ecosystems, clogging is prevented in the Biolytix filter through the action of a number of organisms [292], such as 163 “worms, composting beetles, compost flies and such… typical of a soil layer or decomposing manure” [293]. These larger organisms “create pores throughout the filtration matrix” [292], allowing oxygen to penetrate the column and encourage decomposition in what otherwise would be an anaerobic environment. The larger organisms also “work synergistically with fungi, bacteria, protozoa, nematodes and other microbes” to rapidly and completely decompose all of the solid organic waste deposited [293].

[357]

Selection Criteria Verification #1: The design is truly bioinspired.  “The Biopod… is an ‘ecosystem in a tank’… After 2.1 billion years of Research and Development, nature has got it right. All around us, the natural world is treating its waste… without electricity, without large aerators and without creating septic sludge as a waste product... Biolytix incorporated nature’s time-tested strategies into its patented BioPod… the BioPod uses the intelligence of nature to bring you many benefits” [358].

 “For about a century, engineers have used water-based processes to treat wastewater. By studying ecology, nature’s consummate engineer, Biolytix discovered that nature has a different solution: in nature, the most effective treatment doesn’t happen in water, but in moist soil ecosystems on rainforest floors and on river banks. This is where organisms convert waste into cleaning humus. The humus then helps cleanse the wastewater. Using worms and other organisms to break down organic waste is not an innovation – they have been doing so for millions of years. Our innovation is using nature’s highly effective biological processes to solve today’s challenge posed by wastewater” [359]. 164

 “A design principle to prevent bed buildup on its peripheral surfaces is to enable controlled erosive surface flow to occur over the surface and sides of each bed element module, but to provide sufficient protection to the surface of the bed at the intended long term surface level to prevent erosion of the humus matrix below this level…. The structural support framework can be made in such a way as to provide inherent stabilization of the surface at a defined level much as tree roots provide protection from erosive flood flows to the soil on stream banks but allow material above the root mat to be washed away. A porous net like plastic mesh can provide this stabilization function” [292].

#2: The design is feasible.  According to the Biolytix Southern Africa’s website: “Biolytix is commercially available” [360]. A number of other sources echo this statement and discuss Biolytix as an existing system. However, it appears that Biolytix suffered significant financial losses as a result of a warranty policy concerning flooding and went bankrupt. Regardless of whether Biolytix filters currently are commercially available, it is clear that a commercial Biolytix filter once existed and is therefore feasible.

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  “The Biolytix waste management system draws from the solutions of the natural world to solve the problem of disposing of sewerage solids and liquids and meets several of the goals outlined by the WBCSD [the World Business Council for Sustainable Development] concurrently, thereby creating a more eco-friendly solution” [361].

 “A Biolytix filter is the trademark name for an ecological wastewater treatment system that is totally free of chemical inputs and that has no negative sludge of liquid effluent penetrating the surrounding ecosystems” [362].

 “Due to the efficient manner in which worm farm technology performs, it is not necessary to add large aerating pumps or chemicals” to the Biolytix filtration system [361]. “This in turn reduces… the negative costs to the environment” [361].

 Biolytix filters are smaller than their competitors yet achieve the same amount of filtration. A Biolytix patent states: “Filters according to the present invention have the advantage that their sizes can be significantly less than is required for conventional filters, due to the biological activity present and as a consequence of this specific biological activity the higher filtration rates” [296]. A smaller size is frequently associated with lower lifecycle impact in materials, manufacturing, and transportation.

Competitor Description The Biolytix filter was compared to a conventional septic tank because septic tanks are the most commonly used type of decentralized waste disposal system [363]. As can be seen in the diagrams, below, of two different septic tank designs, septic tanks temporarily store sewage, allowing the sewage to separate based on density. Solid waste sinks to the bottom, scum is captured on the surface, and liquid waste is removed. Because the surface scum prevents oxygen from entering the waste [364], anaerobic conditions are present [363], and anaerobic bacteria cause the solid waste to liquefy [364], making it possible to remove the waste from the system. Periodically, the sludge needs to be removed. This “sludge is not biodegradable” [365].

165

Different types of septic tanks [366,367].

Comparison of Environmental Impact of BID and Competitor The Biolytix filtration system is environmentally superior to a septic system for a number of reasons: (1) Biolytix filters can be smaller than standard filters because of the additional filtration efficiency caused by the river-inspired biological activity in the filter; (2) Biolytix filters do not require aerating pumps, meaning less energy is consumed during use and fewer materials are required during production; (3) Biolytix filters do not require added chemicals, and do not have toxic byproducts; and (4) Biolytix does not have any byproducts such as sludge, and consequently requires less maintenance and has less of an impact during use. Each of these items is explained in a corresponding numbered section below.

(1) Biolytix filters can be smaller than their competitors yet achieve the same amount of filtration. A Biolytix patent claims that their filters can be significantly smaller than conventional filters because of the higher filtration rates associated with the biological activity in the Biolytix filters [296]. Consequently, Biolytix filters have a smaller environmental impact than septic systems during manufacturing and transportation because less materials are required during the production of the filters, and there is less volume and weight of materials to transport.

(2) Biolytix filter use living organisms – such as worms and insects – to aerate the waste so no aerating pumps are needed. “Most traditional septic organic waste disposal systems use technology that leaves the untreated matter in the wastewater. However, to maintain the ecosystem necessary to break down the waste material several aerating pumps are needed. These pumps aerate the waste creating bubbles thereby increasing the surface area of the waste material. This larger physical environment allows a larger population of bacteria to break down waste material” [361]. For a traditional septic system, “The need for aerating pumps to run continuously increases the power consumption and complexity of the system” [361]. “Due to the efficient manner in which worm farm technology performs” in the Biolytix system “it is not necessary to add large aerating pumps… This in turn reduces… the negative costs to the environment” [361].

(3) Biolytix filters do not require the use of added chemicals to treat the waste, and do not create toxic by-products. In typical household wastewater treatment systems, “chlorine based disinfection is typically carried out on the liquid effluent, using hazardous chemicals and resulting in the production of toxic disinfection by-products” [293]. Alternatively, disinfection could occur thorough “a process whereby the liquid is exposed to high levels of artificially generated 166 ultraviolet radiation” [361]. However, in Biolytix filters, the “effluent moves slowly through the bed in a matrix flow” causing the humus to be trapped and accrete in the bed and form “stable aggregates through the action of living organisms in the biolytic filter ecosystem” [292]. “Due to the efficient manner in which worm farm technology performs, it is not necessary to add … chemicals” to the Biolytix filtration system [361]. Hence, “Unlike many conventional treatment processes” the Biolytix filtration process “uses no chemicals” [360].

(4) “Unlike many conventional treatment processes” the Biolytix filtration “process… does not create any by-products such as sludge” [360]. Instead, Biolytix’s “biologically activated filters require little or no maintenance to keep them from blocking” [296]. In contrast, in conventional systems, “Aqueous media such as sewage effluent, water for consumption, swimming pool water, industrial effluent, aquaculture pond water… are commonly filtered with particulate filtering materials… to remove suspended solids and biologically active material. Such filtering materials… are prone to clogging due to microbial growth on the surface of the filter bed... Many sophisticated arrangements have been devised to address this problem of clogging… Unfortunately such methods generally involve high maintenance and have lower treatment performance” [296]. Consequently, many conventional septic waste disposal systems “need an additional ‘sludge’ removal operation to be performed every three to five years to remove the build up of unconsumed waste. This in turn adds to the cost of running the system, as additional general maintenance is required as well as the chemicals necessary to sterilize the wastewater” [361].

167 A.2 DAIMLER-CHRYSLER BIONIC CAR – SHAPE

Field Biological Analogy Environmental Advantage Mechanical Engineering Aerodynamic exterior profile of the Stability and lower coefficient of spotted boxfish (Ostracion friction – reduced fuel consumption meleagris)

Company Competitor Life Cycle Phase Daimler-Chrysler Same car without bioinspired shape, Use estimated using BMW 3 Series Sedan

Biological Analogy Description The spotted boxfish is a stable and efficient swimmer due to its shape. When a boxfish swims, “tiny vortices form along the edges on the upper and lower parts of [its] body to stabilize the fish” [368], allowing it to “maintain a smooth swimming trajectory and a stable position, even in a turbulent sea” [298]. The formation of vortices is controlled, in part, by the keeled carapaces on the boxfish, shown below, that “produc[e] flows and pressure distributions that comprise an efficient, self-correcting system for pitch and yaw” [39]. This increased stability caused by the formation of vortices is believed to result in energy savings during swimming [39,40] because the fish does not have to actively right itself.

Anterior, posterior, and lateral views of the spotted boxfish. Scale bars are 1 cm [39].

Bioinspired Design Description The shape of the body of the Daimler-Chrysler bionic concept car was inspired by the boxfish (Ostracion meleagris) [11], and biologists were involved in its design [368]. The concept car was fully manufactured and can be driven, although it was never produced on a large scale. Despite its boxy shape, the air drag coefficient of the bionic car is 0.19, which indicates that the car is exceptionally aerodynamic [41]. For comparison, the drag coefficient (cw) of the BMW 3 Series, the comparison vehicle, is 0.27 [369].

168

Shape evolution from boxfish to car [40].

Selection Criteria Verification #1: The design is truly bioinspired.  According to Daimler’s website, the Mercedes-Benz bionic concept car is a “vehicle study with the streamlined contours of a boxfish” [368].

 “Applied to automotive engineering, the boxfish is… an ideal example of rigidity and aerodynamics. Moreover, its rectangular anatomy is practically identical to the cross-section of a car body. And so the boxfish became the model” for the Daimler-Chrysler bionic concept car [368].

#2: The design is feasible.  The Daimler website describes the Daimler-Chrysler bioinic concept car as “fully-functioning and driveable” [368].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  “The application of bionics can easily be illustrated by means of the Mercedes concept car called Bionic Car…The vehicle study was made with the most favorable contours of the boxfish as seen from a fluid mechanics point of view. The air drag coefficient of 0.19 was a peak in aerodynamic performance” [41]. This statement indicates that the bionic car is aerodynamic and has low drag as a result of its bioinspired shape. These features are likely to result in lower fuel consumption.

Competitor Description The competitor of bionic-shaped car is the same car that has a standard body shape. In order to have approximate environmental data on this theoretical car, the BMW 3 series sedan was selected because it is approximately the same size as the bionic car. The drag coefficient (cw) of the BMW 3 Series, which is a function of the shape of the car, is 0.27 [369].

BMW 3 Series Sedan [370].

169 Comparison of Environmental Impact of BID and Competitor The Daimler-Chrysler bionic car gets 70 miles per gallon, “about 30 percent more than for a standard- production car” [368]. The Daimler website attributes the low fuel consumption of the bionic concept car to the bioinspired features of the design: “the optimal aerodynamic properties derived from the boxfish and [another bioinspired feature] create the conditions for a low fuel consumption and excellent performance” [368]. A substantial portion of this fuel consumption reduction can likely be attributed to the reduction in drag of the bioinspired car over a standard similarly-sized car, such as the BMW 3 Series Sedan. According to the Daimler website: “with a Cd value of 0.19 the fully-functioning and driveable Mercedes-Benz bionic car is among the aerodynamically most efficient in this size category” [368]. By comparison, the drag coefficient of the BMW 3 Series Sedan is 0.27 [369], significantly greater than the 0.19 measured for the Daimler-Chrysler Bionic Car [368].

170 A.3 DAIMLER-CHRYSLER BIONIC CAR – STRUCTURE

Field Biological Analogy Environmental Advantage Mechanical Engineering Material allocation in bone growth Less material used in the car frame; weight and fuel consumption reduction

Company Competitor Life Cycle Phase DaimlerChrysler Same car without bioinspired Materials and Use structure

Biological Analogy Description Bones change in size and shape depending on how they are stressed in a process called modeling. In modeling, material is added to bones in high stress areas and is removed from bones in low-stress areas [235,236,371]. As a result of the modeling process, bones are both “strong and relatively lightweight”[277].

Porous bone structure [314].

Bioinspired Design Description The frame of the bionic car was designed to be as lightweight as possible using soft kill option (SKO) software. SKO is a finite-element model inspired by bone growth [372] that allocates material only where stresses require.

Model of bionic car’s structure[373]. 171

Selection Criteria Verification #1: The design is truly bioinspired.  According to Daimler’s website, the project to design the Mercedes-Benz bionic concept car was a “unique research project by biologists and engineers” which utilized a “bionic design process for intelligent lightweight construction” [368].

 The Daimler site also states: “bone structures… show how nature achieves maximum strength with the minimum use of materials. Bone structures are always in accordance with actual loads encountered… In consultation with bionics experts, DaimlerChrysler researchers have developed a computer-assisted process for transferring the growth principle used by nature to automobile engineering. It is based on the SKO method (Soft Kill Option)… This bionic SKO process enables an optimal component geometry which meets the requirements of lightweight construction, safety and durability in equal measure” [368].

 On the Daimler press site, the features of the bionic concept car are listed. It states: “Roof structure with large areas of glass, calculated and designed according to the bionic SKO method” [374].

 In a 2009 paper, Mattheck, the developer of the SKO method, states: “SKO is a FEM-based method that is inspired by osteoclasts in bones nibbling away non-loaded parts in the bony structure” [375].

Of course, this design is indirectly bioinspired because the software was created to make bone-like structures; the structure was not directly taken from the appearance of a bone that is loaded similarly to how a car is loaded, for instance.

Additionally, there is some controversy regarding whether SKO software is inspired by tree growth. For instance, Vincent claims that “Soft Kill Option (a finite-element model by Mattheck (1989) developed from his studies on stress-relieving shapes in the adaptive growth of trees) was used to design the chassis of the DaimlerChrysler Bionic Car” [11]. I believe Vincent is either confused or using misleading language here. Mattheck developed two separate optimization tools based on biological studies. SKO is based on bone, while CAO is based on tree growth. I confirmed in an email with Mattheck [372] that SKO software is not inspired by tree growth.

#2: The design is feasible.  The Daimler website describes the Daimler-Chrysler bionic concept car as “fully-functioning and driveable” [368].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  A great potential weight reduction for the bionic structure is associated with the use of bioinspired SKO software in the design: “If the complete body-in-white structure is considered according to the SKO method, the weight is decreased by around 30%, while at the same time, the stability, crash safety, and driving dynamics are excellently maintained” [41]. This weight reduction will translate to a reduction in fuel consumption, and hence, a reduced environmental impact.

 The following quote from Vincent presents a similar estimate for weight savings: “Parts of the recent and much-touted boxfish concept car, a design study by Daimler-Chrysler, used a stress- relieving design tool developed by Claus Mattheck, who studied the growth of trees to gain an 172 insight into how nature would deal with the strength-to-weight problem. The resulting weight savings was on the order of 40 percent” [294]. Although Vincent is mistaken about the biological source of inspiration for the design, discussed above, this quote is still included because the weight savings estimate is presumably still correct. This weight reduction will translate to a reduction in fuel consumption, and hence, a reduced environmental impact.

Competitor Description The competitor of the bioinspired structure of the bionic car is the same car that has a standard frame.

Frame of a typical sedan [376].

Comparison of Environmental Impact of BID and Competitor The Daimler-Chrysler bionic car has around a 30% [41,368] to 40% [294] lower weight and 30% lower fuel consumption than a standard car [368]. The Daimler website attributes the low fuel consumption of the bionic concept car to the bioinspired features of the design: “[another bioinspired feature] and a new lightweight construction concept taken from nature create the conditions for a low fuel consumption and excellent performance” [368].

173 A.4 EASTGATE CENTRE COOLING SYSTEM

Field Biological Analogy Environmental Advantage Architecture Cooling in termite mounds Reduced electricity use

Company Competitor Life Cycle Phase Arup Madrid – Construction Electric air conditioner for a Use Pearce Partnership - Design building of similar size in the same location

Biological Analogy Description At least two models for airflow and cooling exist for termite mounds. The first is for capped chimney termite mounds. In this model, heat from the colony rises to the top of the mound, where the warm air is released through the porous surface, and where cooler, denser air comes in and then sinks to the bottom of the nest [34]. The second model is for open chimney termite mounds. In this model, the top of the mound is above the boundary layer, meaning air blowing past the top of the mound has a higher velocity than air at the openings near the ground; this difference in air velocity generates a Venturi flow which draws in air at ground level, through the mound and out the chimney [34]. These two models are depicted below.

Models of fluid flow in termite mounds [34].

Bioinspired Design Description Eastgate Centre is structured to promote desirable fluid flow. It has a series of chimneys along its length and openings at ground level. Rising heat generated by people and machinery in the building causes thermosiphon flow, and chimneys on the roof, above the boundary layer of the wind, prompt induced flow, drawing hot air out the chimney and cool air in at ground level [34]. The cooling system in Eastgate is also designed to take advantage of the 10 to 14 degree Celsius diurnal temperature swings experienced in Harare, Zimbabwe; the building draws in cool air at night and allows warm air to rise out of the building during the day [32]. Eastgate Centre’s passive cooling system is assisted by fans [29]. At night, the fans draw in cool air at ground level at a rate between seven and ten air changes per hour [29-31], cooling the 174 entire building and the concrete mass upon which the building rests. During the day, cool air is drawn into the building near ground level and is cooled further by the concrete floor that serves as a thermal mass. .

Eastgate Centre exterior [35]. Diagram of airflow in Eastgate Centre [32].

Selection Criteria Verification #1: The design is truly bioinspired.  Mick Pearce, the lead architect for Eastgate, quotes a passage from the 2003 Prince Claus Award he received for the Eastgate design on his curriculum vitae. The passage states: “Based on the termite mound analogy, Mick Pearce’s Eastgate building uses the mass of the building as insulation and the diurnal temperature swing outside to keep its interior uniformly cool” [33]. Although the passage on the award is not considered a reputable source for proving that a design is bioinspired, the fact that Mick Pearce included this passage on his CV indicates that he is, at least, not opposed to the claims made in the passage.

 Additionally, there is a quote from Mick Pearce cited in the book The Architectural Expression of Environmental Controls where Pearce discusses the design of Eastgate Centre. He states: “If the termites could create a natural air-conditioning system, we must be able to use that as a model and that grew and it remained with us for the whole design period” [30].

Although neither of the sources cited above is a direct statement in a primary source, taken together, they provide sufficient evidence that Eastgate Centre was truly bioinspired.

#2: The design is feasible.  Construction of Eastgate was completed in April 1996 [29].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  The associate director of Arup states in peer-reviewed conference paper that, according to data monitoring building performance “subsequent to the completion of construction,” Eastgate “consumes up to 50% less energy than a comparable air conditioned office building” in Harare [32].

175 Competitor Description Eastgate Centre’s passive cooling system was compared to a theoretical similarly-sized office building in Harare with an industrial-sized electric air-conditioning system. A traditional industrial air conditioning system would involve a substantial mass of equipment and would consume a large amount of electricity. In 2008, the most recent year for which data is available, approximately 53% of electricity in Zimbabwe came from hydropower, 46% from coal and peat, and the remainder from petroleum [268].

Industrially-sized electric air conditioner [377]. Much electricity in Zimbabwe is from coal[378].

Comparison of Environmental Impact of BID and Competitor Compared to an industrial air conditioning system run on electricity from hydropower, coal/peat, and petrolum, Eastgate Centre’s passive cooling system is environmentally superior.

First, Eastgate has reduced number of ‘active’ energy inputs compared to a standard industrial air conditioner, i.e. Eastgate consumes less electricity, fossil fuels, and energy from engineered energy- harvesting devices than an industrial air conditioning system would.

Second, Eastgate has reduced carbon emissions because it consumes less electricity than an industrial air conditioning system, and a large percentage of the electricity in Zimbabwe is produced from carbon- intensive sources. As stated above, approximately 53% of electricity in Zimbabwe comes from hydropower [268]. While the relative environmental impact of hydropower compared to other electricity resources is small, there are still significant carbon emissions associated with the construction of dams and flooding of land for dams, as well as an impact on wildlife in the rivers. Additionally, coal, peat, and oil, which make up for the remaining 47% of electricity production in Zimbabwe [268], all have well-know environmentally-damaging effects, particularly with regard to greenhouse gas emissions.

Finally, the energy resources used in Eastgate Centre are more renewable and abundant than the sources of electricity that would be needed to power an industrial air conditioner. The passive cooling system in Eastgate runs for the most part without active energy due to the shape of the building and the dynamics of fluid flow in those spaces. Essentially, this system runs on ambient heat, which is renewable and abundant. In contrast, an industrial air conditioner in Zimbabwe runs on electricity from hydropower, coal, peat, and petroleum. In general, hydropower is considered a renewable energy resource because the supply of freshwater in rivers that generate hydropower is naturally replenished. However, hydropower resources are vulnerable to climate change and extreme weather events, such as drought, meaning these resources are not always renewable and abundant. Additionally, coal, peat, and petroleum are all considered nonrenewable fossil fuel resources. In terms of the abundance of these resources in Zimbabwean context, coal and peat are relatively abundant while petroleum is not; over the last 40 years, Zimbabwe has consistently been able to supply enough coal and peat to meet all of its own needs, but its oil demand has been wholly supplied by imported sources [268]. 176

A.5 INTERFACE FLOR I2 ENTROPY CARPET

Field Biological Analogy Environmental Advantage Artistic design Random patterns on forest floor Reduction in scrap rate and maintenance, longer product life

Company Competitor Life Cycle Phase InterfaceFLOR Conventional modular carpet Use with a nap orientation that needs to be from a particular dye lot

Biological Analogy Description A forest floor is aesthetically attractive and is covered in leaves, sticks, pinecones and a wide range of other materials with different shapes and colors that fall to the ground in random positions. This randomness makes it difficult to spot something that might otherwise look out of place.

A forest floor [379].

Bioinspired Design Description Interface FLOR’s i2 Entropy modular carpet has an artistic design composed of a seemingly random assortment of shapes and colors within the individual tiles. Similar to a forest floor, the random shapes and patterns in the design make it difficult “for any tile to look out of place” [380]. Because of this intentional randomness, one can place tiles from different dye lots and tiles with different nap orientations next to each other without ruining the aesthetics of the carpet [380]. Additionally, the random pattern allows old tiles to be replaced with new tiles from different dye lots, without having the visual differences between old and new tiles and tiles from different dye lots be problematic [380]. Consequently, the randomness incorporated into the artistic design of the tile reduces scrap rates during tile production and installation, and extends the attractive and useful life of the carpet as a whole. 177

i2 Entropy carpet tiles with seemingly random patterns [381].

Selection Criteria Verification #1: The design is truly bioinspired.  According to Eric Nelson, vice president of Interface Americas, “the Interface designed team looked to nature to find a more efficient, less wasteful approach to design. The team noticed that nature produced randomness rather than uniformity (every rock is different in size and shape, no two leaves are the same, etc.). This idea gave birth to Entropy®” [382].

 Interface FLOR’s website: “Using the principles of biomimicry, we created i2TM, our second design platform. Biomimicry seeks sustainable solutions by using nature as a model. Like leaves on a forest floor, i2 tiles vary from one to the other – yet they come together to form a beautiful floor” [279].

The case of Entropy carpet is a borderline case because nature-inspired designs are not necessarily biologically-inspired. If Entropy was inspired by the fact that no two rocks are the same, it would be a geologically-inspired design, not a biologically-inspired one. However, one of the quotations above explicitly states that biomimicry was used to create i2 tiles, and both sources mention being inspired by leaves on a forest floor. Hence, it the Entropy carpet tiles are assumed to be bioinspired.

#2: The design is feasible.  Entropy was launched in early 2000 [383].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  Entropy carpet “mimics the randomness of the forest floor with small sections, or tiles, each composed of different shades of color. Because color matching is no longer a problem, only a worn or damaged section needs replacement” [384]. This suggests that the bioinspired randomness in the pattern allows the carpet as a whole to have a longer use phase.

Competitor Description Typical modular carpet tiles with a specific solid color or pattern are used as the competing product. It is assumed that the patterns on adjacent tiles and their nap direction must be aligned and all tiles - or tiles of the same type – are from the same dye lot [380]. 178

For instance, for the carpet below, it is important that all the logo tiles were created in the same dye lot so that the colors of all the tiles match; the same is true for all the solid blue tiles. If one of the blue tiles was from a different dye lot, and was slightly greener for instance, it would stand out. This means that all the carpet tiles for a particular room and all replacement tiles for that room are purchased at the same time and come from the same dye lot. It also means that when tiles are replaced, the overall appearance of the carpet will be diminished. For instance, after ten years, the carpet below will become faded. If one of the blue tiles were replaced with another from the same dye lot that had been sitting in storage, it would stand out as the only bright and new tile in the room.

Additionally, it is important for all the logo tiles to be facing the same direction and for the checkerboard pattern of tiles to be maintained. If this photo depicted the carpet on a smaller scale, it would become apparent that it is also important to have the nap directions aligned, in much the same way it is important for someone sewing a striped shirt to ensure that the left side of the shirt does not have horizontally- oriented stripes when the right side of the same shirt has vertically-oriented stripes.

Typical carpet tiles [385] have a particular orientation matching colors.

Comparison of Environmental Impact of BID and Competitor The randomness in the artistic design of Entropy carpet tiles reduces scrap rates in production and installation and increases the useable, aesthetically-pleasing life of the carpet as a whole, compared to standard modular carpets. “Given the apparent randomness of the pattern and color scheme, worn or soiled tiles in a particular installation may easily be replaced with and unused tile without the new tile looking as dramatically different from the remaining tiles as often results with tiles with conventional patterns” [380]. Although not here selected as the competing product for analysis, Entropy also presents a sustainability advantage over conventional broadloom carpets for the same reasons – less waste in installation and a longer carpet life. Eric Nelson, vice president of Interface Americas states in an article in Global Business and Organizational Excellence: “Compared with broadloom, which can entail as much as 14 percent waste, Entropy tiles can be installed two-and-a-half times faster and with as little as 1.5 percent waste” [382].

179 A.6 SELF-CLEANING TRANSPARENT THIN FILM

Field Biological Analogy Environmental Advantage Materials Science Lotus leaf Consumes less water and harsh chemicals during cleaning

Company Competitor Life Cycle Phase The University of Tokyo, Sofia Standard surface cleaned using Use University, Daido Institute of spray or ultrasonic aqueous Technology cleaning methods

Biological Analogy Description The leaves of Nelumbo nucifera, or lotus, plant are water-repellant, or hydrophobic, causing water to bead on the surface of the leaf, as is shown in the photograph below. This feature causes the lotus leaf to exhibit self-cleaning properties: “contaminating particles are picked up by water droplets or they adhere to the surface of the droplets and are then removed with the droplets as they roll off the leaves” [17]. This process is depicted in the diagram below on the right. This self-cleaning propensity is known as the ‘lotus effect’ and provides a biological advantage to the plant by allowing it to avoid damage caused by chemical contamination from the air, as well as protecting the it from pathogens, such as spores and conidia, by depriving them of water [17].

Water droplets on a lotus leaf [45]. Diagram of self-cleaning process [386].

Bioinspired Design Description Nakajima et al. [42] present in a 2000 paper a thin film that is transparent, durable, and superhydrophobic, meaning it repels water as the lotus leaf does. Consequently, like the lotus leaf, this thin film also distributes self-cleaning properties. The film can potentially be applied to the surface of parts so that they can be cleaned by spraying a mist of water on the part, as opposed to using spay cleaning or aqueous cleaning techniques [43]. The dirt particles on the surface of the part can then be absorbed into the beads of water that form and roll off the part[27].

180

Surface with self-cleaning coating [44]

Selection Criteria Verification #1: The design is truly bioinspired.  In their 2000 paper in Langmuir, Nakajima et al. mention the connection between their self- cleaning thin film and the lotus leaf: “the excellent hydrophobicity of … superhydrophobic surfaces gradually degrades, in general, during long-time outdoor exposure due to the buildup of stain. This was a crucial and inevitable problem for artificially constructed superhydrophobic surfaces. Natural lotus leaves avoid this problem by continuous metabolism of their surface wax layer and maintain their hydrophobicity during their lifetime. Since a proper metabolic mechanism of lotus leaves is difficult to duplicate, practical applications of superhydrophobic surfaces have been limited” [42]. The authors of this paper take for granted that the lotus leaf is a biological analogy for the self-cleaning thin film they are presenting.

#2: The design is feasible.  Nakajima et al. describe their transparent, superhydrophobic thin films with self-cleaning properties in detail in Langmuir [42]. The thin film is a fully-functional prototype, although the method by which it is produced is still in development. “Although the preparation of superhydrophobic surfaces has been extensively studied, only a few methods have been reported for transparent films thus far”[387], and there is only laboratory scale production. However, the thin films themselves are fully-functional, and the bioinspired innovation is one related to behavior of the product in the use phase, not an innovation in production.

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  A life cycle analysis study from Raibeck et al. examined the environmental impact of the use phase of cleaning gears with a bioinspired self-cleaning surface, compared to gears with a standard surface, cleaned using aqueous cleaning methods. It found “a large water and energy savings when using the self-cleaning surface” [43].

 From a peer-reviewed conference paper from the same research group presenting life cycle analysis results on this self-cleaning transparent thin film presented in the Nakajima et al. paper: “Environmental benefits are obvious in the use phase of a self-cleaning coating, as compared to industrial cleaning methods. Much less energy and water is consumed when cleaning a self cleaning surface, as compared to spay or ultrasonic aqueous cleaning methods. The aqueous cleaning methods also require solvents which create additional environmental burdens” [27].

181 Competitor Description The self-cleaning surface was compared to a standard surface on a part regularly cleaned using either ultrasonic aqueous cleaning or spray cleaning techniques. Raibeck et al. explain the difference between these two cleaning methods:

In ultrasonic cleaning, the part to be cleaned is submerged in a solution of water and solvent, and sound waves are used to produce bubbles through cavitation. The vibration of the bubbles removes contaminants from the part. In spray cleaning, a solution of water and solvent is sprayed from many angles onto a part. Spray cleaning machines often have additional rinse and drying stations. [27]

Because ultrasonic cleaning and spray cleaning are both feasible competitors for the self-cleaning thin film, and because relevant environmental data was available for both methods, both were analyzed.

Ultrasonic cleaning of forceps [388]. Spray cleaning machine [389].

Comparison of Environmental Impact of BID and Competitor A life cycle inventory study of self-cleaning thin film conducted by Raibeck et al. [27] found that, compared to both the spray and ultrasonic cleaning methods, the self-cleaning coating provides environmental benefits during the coating’s use phase because it requires less energy and water. The potential environmental benefits of the self-cleaning surface are countered by the resource consumption and emissions resulting from the production of chemicals used to make the coating; “The production of the self- cleaning coating consumes more than 10 times the energy it takes to clean it” [27]. Consequently, an engineer designing a system must know how often the system will be cleaned during its lifetime and what alternative cleaning methods are available, in order to choose the option with the lowest environmental impact. In this case, if the use phase of the design is expected to overwhelmingly dominate the product’s environmental impact, it is likely that the incorporation of the bioinspired sustainable design solution from the lotus leaf will lead to a more sustainable design.

182 A.7 SHARKLET ANTIMICROBIAL SURFACE

Field Biological Analogy Environmental Advantage Materials Science Surface texture of shark skin Reduced need to clean surface, leading to reduced consumption of toxic chemical during cleaning, and risk of evolution of ‘superbugs’

Company Competitor Life Cycle Phase Sharklet Technologies, Inc. Clorox disinfectant bathroom Use cleaner

Biological Analogy Description “The skin of fast-swimming sharks” has micro ridges on it, called dermal dentricles or riblets [390] that prevent biofouling, the attachment of unwanted microorganisms on a surface [266,390]. These riblets are “aligned in the direction of fluid flow” and are spaced in such a way as to prevent organisms from attaching to the surface [390]. This feature is beneficial to fast-swimming sharks because biofouling organisms create drag and would require the shark to expend more energy while swimming. Because the skin of fast- swimming sharks is void of biofouling organisms, it is considered by some to be “a prominent example of a low friction surface in water” [266].

Left: Topography of shark skin. The bar in the top left is 500 µm [391]. Right: Shark [392].

Bioinspired Design Description Sharklet antimicrobial surfaces are strips that can be applied to a variety of surfaces, such as bathroom door panels or countertops, to control bacterial growth between cleanings. Sharklet strips have a patterned microtopography inspired by shark skin that prevents the growth of bacteria without the use of chemical biocides. In an experiment measuring biofilm formation of Staphylococcus aureus on Sharket surfaces, observations suggested that “the protruded features of the topographical surface provided a physical obstacle to deter the expansion of small clusters of bacteria present in the recesses into microcolonies” [267]. Because bacterial buildup occurs more slowly on Sharklet surfaces, these surfaces need to be cleaned 183 less frequently, meaning less cleaning chemicals are consumed during the life of the surface. Sharklet strips have a life of 90 days [393].

Sharklet topography[264] . Sharklet push door plates [394].

Selection Criteria Verification #1: The design is truly bioinspired. Sharklet’s website, promotional materials, patents, and academic papers from one of Sharklet’s founders indicate that the design for Sharklet is bioinspired and was inspired by the topography of shark skin:

 Sharket’s website tells the story of how Sharklet was developed when the inventor was working on preventing algae from coating vessels for the navy and developed an antifouling strategy based on shark skin. The website states: “Sharklet Technologies is… honored to offer a biomimetic technology inspired by the shark”[264].

 Sharklet promotional materials: “Sharklet is biomimetic – it is inspired by the shape, pattern and microbe resistant properties of shark skin” [395].

 Sharklet patents: “The Sharklet topography is based on the topography of a shark’s skin” [266].

 Peer-reviewed papers from one of Sharklet’s founders: The use of a model correlating wettability with bioadhesion “led to the design concept of a biomimetic structure inspired by the skin of fast-moving sharks (Sharklet AFTM)” [267].

#2: The design is feasible.  Sharklet Surface Protection samples can currently be purchased online on Sharklet’s website and more Sharklet products are sold by Tactivex [394].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  According to a Sharklet patent, Sharklet surfaces reduce the energy required during cleaning: Sharklet surfaces “can provide reduced energy and cost required to clean surfaces of biofouling by reducing biofouling in the first place. As a result, there can be longer times between maintenance/cleaning of surfaces” [266].

 Sharklet is non-toxic. In the ‘Field of the Invention’ section for another Sharklet-related patent, it states: “The invention relates to articles and related devices and systems having surface topography and/or surface elastic properties for providing non-toxic bioadhesion control” (italics mine) [396]. It also states: 184 The present invention describes a variety of scalable surface topographies for modification of bio settlement and bioadhesion, such as bioadhesion of biofouling organisms including, but not limited to, algae, bacteria and barnacles… it has been proven through experimental testing that surface topographies according to the invention provide a passive and non-toxic surface, which through selection of appropriate feature sizes and spacing, can significantly… reduce settlement and adhesion of the most common fouling marine algae known, as well as the settlement of most barnacles (italics mine) [396].

 Additionally, there is reason to believe Sharklet is environmentally advantageous because it does not support the evolution of superbugs. The Sharklet website (not peer-reviewed) states: Sharklet “Offers no risk for antimicrobial resistance. It is the Sharklet-textured surface alone that disrupts bacteria’s ability to survive, not antimicrobial agents that contribute to the development of ‘superbugs’”[397]. There are no claims found in peer-reviewed literature that overtly agree with this statement. However, the claim that Sharklet does not contribute to antimicrobial resistance is supported by biological peer-reviewed literature that describes how superbugs evolve.

“The term ‘superbugs’ refers to microbes with enhanced morbidity and mortality due to multiple mutations endowing high levels of resistance to the antibiotic classes specifically recommended for their treatment” [398]. Superbugs evolve through the widespread use of antibiotics and biocides, such as those found in cleaning products: “The development of generations of antibiotic-resistant microbes and their distribution in microbial populations throughout the biosphere are the results of many years of unremitting selection pressure from human applications of antibiotics, via underuse, overuse, and misuse” [398]. Additionally, “The limited scientific evidence available indicates that bacterial resistance to biocides may contribute to the development and dissemination of antibiotic resistance, which is a serious concern relative to the worldwide anti-infective therapy for humans and animals” [399]. There is no evidence to suggest that products, such as Sharklet, that prevent bacterial growth through non-chemical mechanisms, would contribute to the evolution of superbugs.

Competitor Description Clorox Disinfecting Bathroom Cleaner was selected as an appropriate competitor for Sharklet antimicrobial surfaces because both products could be used to prevent bacteria growth in a bathroom. Clorox disinfecting bathroom cleaner is a chemical cleaner that contains: water, butoxydiglycol, tetrapotassium EDTA (ethylenediaminetetraacetic acid), alkyl polyglucoside, alkyl dimethyl benzyl ammonium chloride, alkyl dimethyl ethylbenzyl ammonium chloride, amine oxides, fragrance, and silicone emulsion [400]. It is meant to be sprayed on dirty bathroom surfaces, allowed to stand for 10 minutes if the user is trying to disinfect the surface, and then be wiped off the surface [401]. Reportedly, it “kills 99.9% of germs commonly found in bathrooms” [402].

185

Clorox Disinfecting Bathroom Cleaner [400].

Comparison of Environmental Impact of BID and Competitor According to its material safety data sheet, Clorox disinfecting bathroom cleaner contains four hazardous substances: (1) Diethylene glycol monobutyl ether (DGBE), (2) Tetrapotassium ethylenediamine tetraacetate (ETDA), (3) n-Alkyl dimethyl benzyl ammonium chloride (ADBAC), and (4) n-Alkyl dimethyl ethylbenzyl ammonium chloride [403].

The second substance listed – ETDA – is not biodegradable. According to DOW Chemical, “Salts of EDTA do not pass tests as ‘readily biodegradable’ ” [404], meaning that a typical bathroom cleaner, such as Clorox, is not biodegradable.

There is strong reason to believe that the third substance - ADBAC - contributes to the development of superbugs. “Although the concentrations of the active agents at the point of application can be generally controlled, sub-lethal exposure to biocide occurs as they become dissipated in the environment” and can consequently exert selection pressure [405]. “The widespread incorporation of antibacterial agents into consumer products has compounded the problem, especially for agents with lower chemical reactivity, such as the quaternary ammonium compounds” (QACs) [405]. QACs “are biocides that have recently come under scrutiny for their role in antibiotic resistance… Many studies have shown that exposure to QACs at subinhibitory concentrations leads to the selection of intrinsically resistant bacteria in a microbial community or results in the development or acquisition of resistance mechanisms” [399]. The Center for Disease lists ADBAC as a quatemary ammonium compound [406]. This implies that use of ADBAC could lead to the development of resistance mechanisms in bacteria and ultimately contribute to the evolution of superbugs.

Additionally, ADBAC is toxic to many different kinds of animals. The EPA categorizes ADBAC “as highly toxic to fish… and very highly toxic to aquatic invertebrates… on an acute exposure basis” [407]. ADBAC is also “moderately toxic to birds” and “slightly toxic to mammals on an acute basis” [407].

In contrast to chemical biocides, such as those found in Clorox, Sharklet is nontoxic and does not contribute to the evolution of superbugs. Instead, the shape, size, and spacing of features on Sharklet’s surface “physically interfere “with the settlement and adhesion of microorganisms” [396]. Sharklet surfaces prevent bacteria growth, meaning that these surfaces stay cleaner longer and consequently need to be cleaned less frequently.

Sharklet has to be thrown away after 90 days and presumably disposed of in a landfill. Clorox most likely is either rinsed down the drain, or is disposed of in a landfill on paper towels and other cleaning supplies.

186 A.8 SHINKANSEN 500 SERIES NOSE CONE

Field Biological Analogy Environmental Advantage Mechanical Engineering Piscivore kingfisher beak Reduction in electricity consumption, Quieter

Company Competitor Life Cycle Phase West Japan Railway Company A standard nose cone, Use Hitachi approximated using the N+P Industrial Design Shinkansen 300 Series

Biological Analogy Description There are two types of kingfishers: piscivores and insectivores. Piscivore kingfishers have a distinctive bill shape, described by some as “narrow black spear-shaped bills” [408], or “needlelike mandibles” [409]. These can be seen in the images below.

Kingfishers [410,411].

Bioinspired Design Description The 500 Series Shinkansen is an award-winning Japanese train that was “Regarded as the fastest electric train in commercial operation in 1998” [412]. It has a maximum operating speed of 300 km/h, and a maximum speed of 320 km/hr [413].

However, higher train speeds are associated with higher noise, and “In Japan, noise is said to be the greatest impediment to raising commercial speeds” of trains [414]. Noise is particularly an issue when tracks run through tunnels, and “Half of the entire Sanyo Shinkansen Line (from Osaka to Hakata)” – where the 500 series Shinkansen runs – “is made up of tunnel sections” [415]. “When a high-speed railway train enters a tunnel, a compression wave is generated ahead of the train and propagates along the tunnel. Subsequently this wave is emitted outward from the exit toward the surrounding area as an impulsive wave which causes an impulsive noise like a sonic boom produced by a supersonic aircraft” [416]. This boom and aerodynamic vibration for some trains has been “so intense that residents 400 meters away have registered complaints” [415]. Consequently, measures had to be taken during the design of the 500 Series Shinkansen to reduce noise. 187

High speed trains create compression waves in tunnels, causing a loud noise when it exits [417].

One of the noise-reduction measures was to change the shape of the train’s nose cone to better handle the transition from low pressure air to high pressure air found in tunnels. The shape of the nose cone was inspired by the shape of a kingfisher’s beak, as described previously. “The Shinkansen bullet train design uses a conical nose to achieve high speeds and reduce noise while exiting tunnels” [62]. The nose “has a streamline shape that is 15m in length and almost round in cross section” [415].

Left: Shinkansen nose cone [418]. Right: Sketch connecting Shinkansen’s tunnel exit to kingfisher [419].

Selection Criteria Verification #1: The design is truly bioinspired.  Eiji Nakatsu, the director responsible for test runs of the 500 Series Shinkansen, recalls how the nose cone of the Shinkansen came to be inspired by the kingfisher:

[O]ne of our young engineers told me that when the train rushes into a tunnel, he felt as if the train had shrunk. This must be due to a sudden change in air resistance, I thought. The question the occurred to me - is there some living thing that manages sudden changes in air resistance as a part of daily life? … To catch its prey, a kingfisher dives from the air, which has low resistance, into high-resistance water, and moreover does this without splashing. I wondered if this is possible because of the keen edge and streamlined shape of its beak. So we conducted tests to measure pressure waves arising from shooting bullets of various shapes into a pipe and a thorough series of simulation tests of running the trains in tunnels, using a space research super-computer system. Data analysis showed that the ideal shape for this Shinkansen is almost identical to a kingfisher's beak [415]. 188

While overcoming differences across the air/water interface is critical for the kingfisher to be successful fishing, and this interface represents an abrupt change in pressure, there is no evidence in biological literature indicating that the shape of the kingfisher’s beak is particularly well-suited for overcoming this transition. In contrast, a number of authors describe splashes when the kingfisher dives. Skutch describes the fishing behavior of the Amazon Kingfisher: “Suddenly the wings close, the hazy circles vanish, the kingfisher plunges swiftly downward, head foremost and breaks the surface with a splash”[420]. Remson refers to the disruption caused by the dive of a kingfisher: “After a dive, a kingfisher almost always moved to a new perch overlooking a new patch of water. The disturbance created by the dive probably alerted small fishes in the area to surface predation, and it was then presumably more profitable to move on” [421]. Marshall describes the loud plop Azure Kingfisher’s make while fishing: “It was interesting to watch the birds dive into water only a few inches deep from a considerable height, strike the surface with a loud ‘plop,’ turn swiftly, and fly to the same bough with their catch” [422].

While the biological phenomenon that inspired Nakatsu may not be supported by the biological literature, or may not be unique to kingfishers and therefore not prominently discussed in literature on kingfishers, is of little consequence. As in the case of Eastgate Centre’s cooling system, all that is critical is that the design was inspired by nature, not that the designer understood the natural system completely.

#2: The design is feasible.

 The Shinkansen 500 Series has been in operation since 1997 [413,277].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.

Both of the environmental claims made about the nose cone of the Shinkansen 500 series – (1) that it reduces the electricity consumption of the train and (2) that it is quieter – are somewhat problematic, although both prove to be sufficiently supported in the literature as representing a true and meaningful environmental impact reduction.

 First, claims are frequently made in gray literature indicating that the shape of the kingfisher- inspired nose cone has reduced the electricity consumption of the train. For instance, Eiji Nakatsu states in his Japan for Sustainability Newsletter interview that the shape of the nose cone “has enabled the new 500-series to reduce air pressure by 30% and electricity use by 15%, even though speeds have increased by 10% over the former series” [415]. This source is cited in a number of reliable online sources, including Ask Nature [423]. These same numbers also appear in an article in Wired Science [277].

Additionally, there are numerous related, albeit less explicit, statements in academic literature. For instance, books on the 500 Series Shinkansen describe the train as a “synthesis of aerodynamics, technology, and design” [412] and as having “an extremely aerodynamic profile” [424]. Also, observations have been made indicating that the 500 series generates less wind than other trains when existing tunnels, despite the fact that it is moving faster [413]. These statements referring to ‘aerodynamic’ profiles and a reduction in wind imply that the train has less drag and, consequently, would consume less electricity, as is claimed in the gray literature. These statements taken together indicate that there truly is a reduction in electricity

189 consumption of the Shinkansen as a result of its bioinspired nose cone.

Finally, it is not surprising that the noise-reduction aspects of the nose cone are more heavily emphasized in the literature than the reduction in electricity consumption. An article in the Japan Railway and Transport Review confirms: “noise and vibration are two areas of particular attention in Japan because reducing them ensures a better environment for trackside residents. In general, aero-acoustic noise is reduced by using smooth exterior surfaces and reduced air resistance is a bonus” [414]. Since the attention of the designers and Japanese community members appears to have been on noise reduction – and not environmental impact in general – it is not surprising that a discussion on the reduced environmental impact is not prominent in literature on this topic.

 Second, numerous academic sources agree that the 500 Series Shinkansen is quieter as a result of its bioinspired nose cone. o A refereed conference paper states: “The Shinkansen bullet train design uses a conical nose to… reduce noise while exiting tunnels” [62]. o A book on the Shinkansen trains agrees: the author observed while “Standing next to tunnels along the Sanyō Shinkansen,” that “While the 500-series shinkansen was travelling at 300 km/hr, it was often the 0-series travelling some 90 km/hr slower that made the most noise” [413]. The noise reduction is likely due to a variety of factors, including the kingfisher-inspired profile.

Claims are also made in gray literature that the 500 Series Shinkansen is quieter as a result of its bioinspired nose cone. o An article in Wired Science states that “By modeling bullet train noses on kingfisher beaks, West Japan Railway Company engineers created the 500 series… The trains are quieter, 10 percent faster and use 15 percent less electricity” [277]. o Ask Nature states: “The Shinkansen Bullet Train has a streamlined forefront and structural adaptations to significantly reduce noise resulting from aerodynamics in high-speed trains” [282].

This claim that the reduced noise output by the Shinkansen is an environmental benefit may be problematic because product noise may not be considered a true or significant environmental impact. Instead, it may be viewed as a purely aesthetic feature of the product, or as a local and immediate environmental impact that is not of interest if one is looking at environmental impact from a global or national perspective. However, as discussed in Chapter 2, noise is considered a true environmental impact in this analysis. Additionally, number of other reputable sources describe noise as having a true environmental impact. o The United States Environmental Protection Agency (EPA) considers noise to be pollution [425]. o Tanaka et al. discuss noise standards as ‘environmental standards’ that affect the ‘living environment’; “very strict environmental quality standard against Shinkansen noise is applied for the purpose of keeping a pleasant living environment” [426]. o OECD documents refer to ‘noise emissions’ in the context of a discussion on globalization, transportation, and the environment; “International road and rail freight transport accounts for a minor, but increasing , share of global transport emissions of air pollutants (e.g. NOx) and noise emissions” [427]. o Hood refers to noise pollution: “Another significant environmental issue in Japan is noise pollution” [413] o Horihata et al. also refer to noise pollution : “In regard to running Shinkansens at high speed, it is necessary to face… a variety of environmental concerns” such as “the 190 environmental problem of noise pollution” [428]. o Soejima, the president of Japan’s Railway Technology Research Institute (RTRI), writes in a 2003 article that the most significant environment-related research area for the railway in Japan has been related to reducing noise from the trains. “[N]oise and vibration are two areas of particular attention in Japan because reducing them ensures a better environment for trackside residents” [414]. “So far, environmental R&D in Japan has been aimed at resolving problems of trackside noise and vibrations. In the future, greater attention will have to be paid to examining noise sources, analyzing sound transmission paths, and developing better ways to evaluate low-frequency vibration. But the impact of railways on the global environment also needs examining from the perspectives of energy conservation, global warming, waste disposal and recycling” [414].

Anthropogenic noise has negative effects on human and animal health. In humans, “Noise interferes with complex task performance, modifies social behavior and causes annoyance. Studies of occupational and environmental noise exposure suggest an association with hypertension… In both industrial studies and community studies, noise exposure is related to catecholamine secretion. In children, chronic aircraft noise exposure impairs reading comprehension and long-term memory and may be associated with raised blood pressure” [429].

Noise has also been shown to have a negative impact on birds. “Traffic noise is known to have a negative impact on bird populations” [430]. “Road traffic has negative impacts on the density of breeding birds in many parts of the world” [431]. “In open landscapes, only noise and visual stimuli can explain the observed effects” and in forests, only noise can [431]. Noise from railways may divide habitats for animals adverse to the noise, “contributing to ‘islandification’, separating communities and often reducing gene flow” [432]. Islandification may have long- term evolutionary effects on the species.

Competitor Description The competitor of the nose cone of the 500 Series Shinkansen train is the nose cone of the 300 Series Shinkansen train, shown below.

The Shinkansen 300 [433]. 191

Comparison of Environmental Impact of BID and Competitor The use stage of Shinkansen trains has been found to overwhelmingly dominate the life cycle environmental impact of the trains. A life cycle assessment (LCA) study from Miyauchi et al. [434] comparing the environmental impact of variations of Shinkansen Series 0, Series 100, and Series 300 trains found that more than 95% of life cycle energy consumption (LCE) and the lifecycle CO2 emissions (LCCO2) occurs in the use phase of the train. These findings strongly suggest that the use phase of the Shinkansen 500 series is likely to dominate the environmental impact of the train.

Miyauchi et al. [434] also found that “Given the same conditions (number of stations where the train stops, and the maximum speed), both LCE and LCCO2 reduce according to the series number (0 series, 100 series, 300 series). This can be considered to be bought about mainly from the effects of improvement such as lightening the vehicle, use of the regenerative brake, and reduction of running resistance” [434]. Consequently, it is also likely that seemingly minor improvements in the running resistance of the Series 500 due to the modifications inspired by the kingfisher are likely to substantially reduce the environmental impact, compared to a standard train, over the life of the train.

The bioinspired nose cone is quieter than a nonbioinspired nose cone, and is also likely more aerodynamic. Consequently, the bioinspired nose cone on the Series 500 Shinkansen will likely have reduced electricity consumption, compared to a train with a standard pantograph. Both these environmental benefits occur in the use phase of the train. Additionally, the information above suggests that even minor improvements in the efficiency of the train in the use phase are likely to substantially affect the environmental impact of the train as a whole, since the use phase dominates the environmental impact of trains.

192 A.9 SHINKANSEN 500 SERIES PANTOGRAPH

Field Biological Analogy Environmental Advantage Mechanical Engineering Owls’ serrated primary feathers Reduction in electricity consumption, Quieter

Company Competitor Life Cycle Phase West Japan Railway Company Standard pantograph without Use Hitachi serrations N+P Industrial Design

Biological Analogy Description Owls are extraordinarily quiet fliers [415] because of their serrated primary feathers [435,436], shown in the photograph below. These serrated feathers are located on the leading edge of owls’ wings [436]. These feathers break “down turbulence into smaller currents called micro-turbulences” which are then absorbed by the soft feathers on the owl [435]. Because noise is a direct result of turbulence generated during flight, the noise from the owl’s flight is effectively muffled [435,436].

How Owl Feathers Work[435]; Screech owl’s serrated edge of primary feather [437]; Magnified “[s]errations of the 10th primary of a barn owl”[436].

Bioinspired Design Description The 500 Series Shinkansen is an award-winning Japanese train that was “[r]egarded as the fastest electric train in commercial operation in 1998” [412]. It has a maximum operating speed of 300 km/h, and a maximum speed of 320 km/hr [413].

However, higher train speeds are associated with higher noise, and “In Japan, noise is said to be the greatest impediment to raising commercial speeds” of trains [414]. “One of the most important factors to reduce noise outside the Shinkansen is the system for transferring current to the train. This system consists of a pantograph and an insulator” [438]. For an electric train, the pantograph is “The mechanism that collects electricity from the overhead cables” [413]. “The noise created around the pantograph is due to both the contact between the pantograph itself and the overhead wires, as well as the air friction upon the

193 pantograph and its shields as the train moves at speed” [413]. “[A] large… noise is generated when the air hits pantographs, the current collectors that receive electricity from the overhead wires” [415].

To address the problem with noise on the pantograph due to air friction, “‘serrations’ were inscribed on main part of the pantograph, and this succeeded in reducing noise enough to meet the world's strictest standards. This technology is called a ‘vortex generator’” and is inspired by owls’ serration feathers [415].

Pantograph mechanism of 500 Series Shinkansen based on serration feathers (note the owl picture in the museum plaque on right) [439,440].

Selection Criteria Verification #1: The design is truly bioinspired.  Eiji Nakatsu, an active member of the Wild Bird Society of Japan and “the director responsible for the test runs of the Shinkansen series” recalls: “I had the honor of meeting Mr. Seiichi Yajima, then an aircraft design engineer and also a member of the Wild Bird Society of Japan. From him I learned how much of current aircraft technology has been based on studies of the functions and structures of birds. I learned that the owl family has the most silent fliers of all birds... It seems that the owl family has acquired the function of "quiet flying" so that prey such as mice, will receive no warning that the owl is about to strike. Inspired by this fact, we conducted wind tunnel tests to analyze the noise level coming from a flying owl, using a stuffed owl courtesy of the Osaka Municipal Tennoji Zoo. We learned that one of the secrets of the owl family's low-noise flying lies in their wing plumage, which has many small saw-toothed feathers protruding from the outer rim of their primary feathers… These saw-toothed wave feathers are called "serration feathers," and generate small vortexes in the air flow that break up the larger vortexes which produce noise. It took 4 years of strenuous effort by our younger engineers to practically apply this principle. Finally, "serrations" were inscribed on main part of the pantograph, and this succeeded in reducing noise enough to meet the world's strictest standards” [415].

#2: The design is feasible.  The Shinkansen 500 Series has been in operation since 1997 [413,277].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  It is likely that the owl-inspired serrations on the 500 Series pantograph reduce the drag on the train. A number of journal and book authors imply that this is the case, although none both 194 make this statement directly and describe the bioinspired feature of the pantograph precisely.

In a journal article, Koganezawa et al. [441] discuss how the incorporation of owl-inspired serrations in transportation vehicles have been shown to decrease drag, implying that this is likely the case in the 500 Series pantograph as well: “Generally, flow separations due to vortices cause the increase of drag force.” “In the air-plane industry, ‘vortex generators’ which have the same mechanism as” serrations on owl feathers “make small vortices and help boundary layer separation delay downstream” [441]. By delaying boundary layer separation, these ‘vortex generators’ reduce the drag force on the plane wing. Vortex generators inspired by owl serrations “are used to reduce drag force and improve mileage of cars” [441]. They also state: “To reduce running noise of Shinkansen, Japanese bullet train, the vortex generators have been also applied to its pantograph” [441], implying that the drag reduction seen in both airplanes and cars would likely be seen in the case of the pantograph as well.

In a book on Shinkansen trains, Hood states: “The noise created around the pantograph is due to both the contact between the pantograph itself and the overhead wires, as well as the air friction upon the pantograph and its shields as the train moves at speed” [413]. This means that a reduction in noise could be caused by a reduction in air friction on the pantograph, and consequently would reduce the drag on the train. As shown below, the owl-inspired pantograph causes a reduction in noise, meaning that there is also possibly a reduction in air friction, and consequently drag force, on the pantograph as a result.

In a book on Bullet Trains, Biello directly states: “The 500 Series also uses an innovative pantograph design… which helps reduce wind resistance” [424]. Unfortunately, he describes the pantograph as being "shaped like a wing” [424] which is somewhat incorrect or inexact; the pantograph is not shaped like a wing, but it has serrations on it shaped like serrations feathers. It is possible, however, that the author is correct in stating that the bioinspired feature reduces wind resistance.

 Journal articles and books indicate that the 500 Series Shinkansen is quieter as a result of its bioinspired pantograph. o Koganezawa et al. [441] explain: “To reduce running noise of Shinkansen, Japanese bullet train, the vortex generators” inspired by owl serrations “have been also applied to its pantograph.” o In addition, Hood’s observations show that the 500 series is quieter than competitors. He observed while “Standing next to tunnels along the Sanyō Shinkansen,” that “While the 500-series shinkansen was travelling at 300 km/hr, it was often the 0-series travelling some 90 km/hr slower that made the most noise” [413]. The noise reduction is likely due to a variety of factors, including the owl feather-inspired pantograph.

More explicit claims regarding the reduction in noise from the bioinspired pantograph have been made in gray literature. o In his interview with Japan for Sustainability, Nakatsu [415] states that “‘serrations’ were inscribed on the main part of the pantograph, and this succeeded in reducing noise enough to meet the world’s strictest standards” for the 500 Series Shinkansen. o AskNature’s site for the Shinkansen states that “Engineers were able to reduce the pantograph’s noise by adding structures to the main part of the pantograph to create many small vortices… similar to the way an owl’s primary feathers have serrations” [282].

195 Additionally, the incorporation of serrations has been shown to reduce noise in studies on airplanes, increasing the likelihood that they could do so on train pantographs. o Bachmann et al [436] explain: “In aviation, serrations might act as turbulence generators at the leading edge of the wing. In a series of papers from the early 1970s… several wind tunnel experiments were performed to investigate the impact of artificial two-dimensional serrations of different length and spacing in the flow field. In these studies, serrations influenced the air flow separation, enhanced lift of the wings, and reduced noise generated by the wings.” o Koganezawa et al. [441] concur: “In the air-plane industry, ‘vortex generators’ which have the same mechanism as the serrations” in owls “have been used in terms of… noise reduction.”

Competitor Description The competing product is a standard 500 series pantograph without the serrations inspired by the owl feathers. Instead, the competing pantograph would have smooth sides.

Comparison of Environmental Impact of BID and Competitor The use stage of Shinkansen trains has been found to overwhelmingly dominate the life cycle environmental impact of the trains. A life cycle assessment (LCA) study from Miyauchi et al. comparing the environmental impact of variations of Shinkansen Series 0, Series 100, and Series 300 trains found that more than 95% of life cycle energy consumption (LCE) and the lifecycle CO2 emissions (LCCO2) occurs in the use phase of the train [434]. These findings strongly suggest that the use phase of the Shinkansen 500 series is likely to dominate the environmental impact of the train.

Miyauchi et al. also found that “Given the same conditions (number of stations where the train stops, and the maximum speed), both LCE and LCCO2 reduce according to the series number (0 series, 100 series, 300 series). This can be considered to be bought about mainly from the effects of improvement such as lightening the vehicle, use of the regenerative brake, and reduction of running resistance” [434]. Consequently, it is also likely that seemingly minor improvements in the running resistance of the Series 500 due to the modifications of the pantograph inspired by owl feathers are likely to substantially reduce the environmental impact.

The bioinspired pantograph is quieter than a nonbioinspired pantograph, and is also likely more aerodynamic. Consequently, the bioinspired pantograph on the Series 500 Shinkansen will likely have reduced electricity consumption, compared to a train with a standard pantograph. Both these environmental benefits occur in the use phase of the train. Additionally, the information above suggests that even minor improvements in the efficiency of the train in the use phase are likely to substantially affect the environmental impact of the train as a whole, since the use phase dominates the environmental impact of trains.

196 Appendix B: Design Library Designs with Insufficient Information

Information on 6 BIDs – Airbus 320, Baleen Water Filters, Passive Walking Bipedal Robots, Calera Cement, Geckel, and the HotZone Radiant Heater – is presented in Appendix B. The same format used for the designs in Appendix A was also intended to be used here. However, designs presented in Appendix B had insufficient information to positively identify them as sustainable BIDs. Information that was unavailable is not included. Occasionally information from less-reputable sources, or a source citing information of interest, was included with the hope that someone continuing the work could confirm this information in more reliable sources or in the original source. Additionally, as these designs were not selected for analysis, the information contained in these design library entries is more frequently in the form of relevant quotations from authoritative sources, as opposed to more synthesized material.

197 B.1 AIRBUS 320

Field Biological Analogy Environmental Advantage Aeronautical Engineering Shark skin riblets Unconfirmed

Company Competitor Life Cycle Phase Airbus Standard surface Use

Biological Analogy Description “As do many fast-swimming marine organisms, sharks pay a large metabolic cost to overcome the drag on their body surface. The skin scales of some sharks possess tiny ridges that run parallel to the longitudinal body axis. The grooved body surface reduces drag through its influence on the boundary layer ” [273].

“Shark skin has a unique microstructure that appears to serve multiple functions for the shark. In the case of fast-swimming sharks, arguments can be made that the microgeometry associated with the shark skin reduces drag allowing for higher swimming speeds and increased turning ability on some species. The majority of the research has involved deducing the turbulent skin-friction drag-reduction capabilities of the shark skin microgeometry consisting of streamwise riblets, although the separation control mechanisms that may be present have also been considered. Finally, current biomimetic technological applications of shark skin microstructure are reviewed, including shark skin swimsuits to anti-fouling surfaces for ocean-going vessels” [442].

Bioinspired Design Description “Riblet sheets, modeled on shark skin, reduced the fuel consumption of an Airbus 320 when placed over the wings and fuselage.” [273]. “Riblets are small surface protrusions aligned with the direction of flow, which confer an anisotropic roughness to a surface. They are one of the few techniques that have been successfully applied to the reduction of the skin friction in turbulent boundary layers, both in the laboratory and in full aerodynamic configurations” [443].

Selection Criteria Verification #1: The design is truly bioinspired.

#2: The design is feasible.  “Airbus has launched its new "Sharklet" large wingtip devices, specially designed to enhance the eco-efficiency and payload-range performance of the A320 Family. Offered as a forward-fit option, Sharklets are expected to result in at least 3.5 percent reduced fuelburn over longer sectors, corresponding to an annual CO2 reduction of around 700 tonnes per aircraft. The A320 will be the first model fitted with Sharklets, which will be delivered around the end of 2012, to be followed by the other A320 Family models from 2013. Air New Zealand is the launch customer for the Sharklets which are specified for its future A320 fleet” [444].

#3: The design has a reduced environmental impact as a result of its bioinspired feature. 198  “Riblet sheets, modeled on shark skin, reduced the fuel consumption of an Airbus 320 when placed over the wings and fuselage” [273].  “Riblets have been used successfully to reduce the overall drag of aerofoils [12] and aircraft [13] with optimum riblet spacings of the order of 30–70 mm. Szodruch [14] reports on the flight tests of a commercial aeroplane (Airbus 320) with riblets over 70 per cent of its surface, and estimates an overall 2 per cent drag reduction, based on the fuel savings obtained. A summary of those tests, including maintenance and durability issues, can be found in Robert [15]. The discrepancy between the optimum laboratory performance and full configurations is probably to be expected from any method based on the reduction of skin friction. Not all the drag of an aircraft is friction [16], and much of the latter is distributed over three-dimensional or geometrically complex areas where drag control is difficult to optimize. Note that those limitations might not apply to configurations that are very different from commercial aircraft, such as gliders or other high-performance vehicles” [443].

199 B.2 BALEEN WATER FILTERS

Field Biological Analogy Environmental Advantage Mechanical Engineering Baleen whales (also called Unconfirmed whalebone whales or great whales)

Company Competitor Life Cycle Phase Baleen Filters Pty Limited Standard filter Use

Biological Analogy Description “[B]aleen whales such as fin whales (Balaenoptera physalus), which gulp-feed as they swim, use and inward push in front and outward pull on the side (or lower side) to reopen their enormous mouths and expand their throats. Contraction of the muscles of the conspicuously corrugated throats pushes water and food through their baleen plates as the mouth closes. So as the whale swims that combination of muscle contraction followed by pressure-driven expansion pumps the vast volumes of water it needs to process” [445].

According to the Baleen Filters website: “The word ‘Baleen’ is an anatomical description for the whalebone that belongs to a group of filter-feeding whales. The baleen is essentially the filter mechanism that enables the whale to collect plankton, small fish and other marine organisms from the water during feeding. The combination of a sweeping action of the tongue and the reversing of the water flows as the whales dive and re-surface during feeding, enable them to capture and strain food, then clean their baleen prior to the next dive”[446].

Diagram and photo of baleen whale [447].

200

Bioinspired Design Description “A new dimension in separation technology, a self-cleaning filter, originally patented by the University of South Australia and critically tested by industry. It is now being sold under the ‘Baleen’ Trademark…The Baleen Filter technology is an adaptation of this natural technique used by whales to keep their baleen clean and free from long-term deposits.”[446]. “Baleen Filter technology provides non-pressurised separation to 25 microns without chemical assistance, and to 3 microns with chemical assistance. The Baleen Filter removes suspended organics, fines, bacterium and sands from wastewater streams”[448]. According to a patent related to the filter, the goal of the design was “to produce a filtration system which more readily and continually clears accumulating contaminants from a filter medium during a filtering process” [449]. “The Baleen Filter uses a double act of high pressure, low volume sprays, one which dislodges material caught by the filter media, whilst the other spray sweeps the material away for collection. This process removes even the most troublesome of constituents such as grit, suspended and fibrous matter, grease and oil from water without blocking the filter. As water flows through the filter media, solids initially suspended in the water are left behind. But before they accumulate to block the screen media the second spray transports these contaminants away from the filtering zone, enabling the filtering process to continue without disruption” [448].

Baleen water filter [450,451].

Selection Criteria Verification #1: The design is truly bioinspired.  According to the Baleen website: “The baleen is essentially the filter mechanism that enables the whale to collect plankton, small fish and other marine organisms from the water during feeding. The combination of a sweeping action of the tongue and the reversing of the water flows as the whales dive and re-surface during feeding, enable them to capture and strain food, then clean their baleen prior to the next dive. The Baleen Filter technology is an adaptation of this natural technique used by whales to keep their baleen clean and free from long-term deposits.”[446].

#2: The design is feasible.  According to the Baleen Filters website: “The Baleen Filter can be ordered directly from us or via one of our representatives. You can purchase an appropriate unit or lease one from us” [452].

201 #3: The design has a reduced environmental impact as a result of its bioinspired feature.  According to one of Baleen’s European patents: “This invention relates to an improved form of filter, and in particular to a filter having a novel means of clearing contaminants from the upstream or filtration side of the filter to thereby increase filtering efficiency”[453]. However, it is unclear that this additional filtering efficiency is a direct result of the bioinspired feature.

 Additionally, the Baleen Filters website (a non-peer-reviewed source) provides a list of the major benefits of the filters for industry. This list includes a number of claimed environmental benefits, including: “Small footprint - saving valuable land;” “Environmentally friendly, reduced or no chemicals required;” “Low operating costs, low energy needs and low maintenance;” and “Simplicity in industrial wastewater management” [448]. It is possible that some or all of these claims are valid and could be confirmed in peer-reviewed sources. However, claims made on the Baleen website are not considered sufficient for the purposes of this analysis.

Conclusion: Evidence that the Baleen filter meets criterion #3 as a result of its bioinspired feature is likely to be found in peer-reviewed sources but is still required.

Competitor Description The competing product is a standard filtration system discussed in the Baleen patent. In a standard filtration system, the particles being filtered out of the fluid are captured in a way that obstructs the fluid flow and eventually requires cleaning of the filtration device [449]. “Typical cleaning processes include: periodic back flushing where the direction of fluid flow through the filter medium is reversed; and mechanical scraping where a scraper traverses the surface of the filter medium to remove contaminants thereby exposing the filter medium to damage. These cleaning processes interrupt the filtering process and therefore introduce inefficiencies. Furthermore, in some applications it is impractical to clean the filter medium frequently enough to prevent build up of contaminant on the filter medium surface using those cleaning processes and therefore poor filtration efficiencies result. While there exist numerous types of self- cleaning filters their limitations include: the types of fluids that they are able to filter, their durability, the flow rates achievable and the operational time of the filtration process before shutdown is required” [449].

202 B.3 PASSIVE WALKING BIPEDAL ROBOT

Field Biological Analogy Environmental Advantage Robotics Human walking Passive (energy efficient) walking

Company Competitor Life Cycle Phase University researchers Actively-controlled walking Use robot, Honda Asimo

Biological Analogy Description Humans walk efficiently on two legs without high-power or high-frequency actuation [311]. While walking, humans push off with their ankles and have “powered leg swinging” [311]. Whittington et al. [316] showed experimentally that the stretching of soft tissues in the hips and ankles of humans creates passive moments, allowing for energy absorption while the leg swings, accounting for up to “35% of the net hip flexor moment” and approximately 15% of net plantarflexor work.

Bioinspired Design Description “In contrast to mainstream robots, which actively control every joint angle at all times, passive-dynamic walkers do not control any joint angle at any time” [311]. “Passive-dynamic walkers are simple mechanical devices, composed of solid parts connected by joints, that walk stably down a slope. They have no motors or controllers, yet can have remarkably humanlike motions… Here we present three robots based on passive-dynamics, with small active power sources substituted for gravity, which can walk on level ground. These robots use less control and less energy than other powered robots, yet walk more naturally, further suggesting the importance of passive-dynamics in human locomotion” [311].

“Three level-ground powered walking robots based on the ramp-walking designs… (A) The Cornell biped. (B) The Delft biped. (C) The MIT learning biped” [311].

203

Selection Criteria Verification #1: The design is truly bioinspired.  “Each of the robots here has some design features that are intended to mimic humans. The Cornell and Delft bipeds use anthropomorphic geometry and mass distributions in their legs and demonstrate ankle push-off and powered leg swinging, both present in human walking (14, 19). They do not use high-power or high-frequency actuation, which are also unavailable to humans. These robots walk with humanlike efficiency and humanlike motions (Fig. 4 and movies S1 to S3). The motor learning system on the MIT biped uses a learning rule that is biologically plausible at the neural level (20). The learning problem is formulated as a stochastic optimal feedback control problem; there is emerging evidence that this formulation can also describe biological motor learning (21)” [311].

 “A common misconception has been that gravity power is essential to passive-dynamic walking, making it irrelevant to understanding human walking. The machines presented here demonstrate that there is nothing special about gravity as a power source; we achieve successful walking using small amounts of power added by ankle or hip actuation. We expect that humanoid robots will be improved by further developing control of passive-dynamics–based robots and by paying closer attention to energy efficiency and natural dynamics in joint- controlled robots (26). Whatever the future of humanoid robots, the success of human mimicry demonstrated here suggests the importance of passive-dynamic concepts in understanding human walking” [311].

#2: The design is feasible.  Numerous fully-functional prototypes exist. See photos above.

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  “These robots use less control and less energy than other powered robots, yet walk more naturally” [311].

 In general: “Traditional direct drive actuation system of robotic manipulators is probably one of the easiest ways to actuate robotic walkers, due to its simplicity in mechanical implementation and the fact that the rotational motion of motors is directly mapped into rotational motion of the joints. Consequently, if we just require an appropriate functionality of a robotic walker, the direct drives with a gear set would be a convenient solution. However, biological walkers that use an inverted pendulum like mechanism [1, 2, 3] are considered energy efficient relatively with respect to the state of the art robotic walkers [12, 13], using a different kind of actuators, the muscles, which can be considered as elastic (stretchable) linear actuators. Energy efficiency and the level of walk cycle precision and smoothness are among important reasons for mimicking biological walkers” [312].

Competitor Description The competitor is the Honda Asimo, an actively-controlled walking robot with motors and actuators controlling all aspects of the walking motion.

Comparison of Environmental Impact of BID and Competitor “To compare efficiency between humans and robots of different sizes, it is convenient to use the dimensionless specific cost of transport, ct 0 (energy used)/(weight _ distance traveled). In order to isolate 204 the effectiveness of the mechanical design and controller from the actuator efficiency, we distinguish between the specific energetic cost of transport, cet, and the specific mechanical cost of transport, cmt. Whereas cet uses the total energy consumed by the system (11 W for the Cornell biped), cmt only considers the positive mechanical work of the actuators (3 W for the Cornell biped). The 13-kg Cornell biped walking at 0.4 m/s has cet , 0.2 and cmt , 0.055. Humans are similarly energy effective, walking with cet , 0.2, as estimated by the volume of oxygen they consume (VO2), and cmt , 0.05 (12–14). Measurement of actuator work on the Delft biped yields cmt , 0.08. Based on the small slopes that it descends when passive, we estimate the MIT biped to have cmt Q 0.02. Although the MIT and Delft bipeds were not specifically designed for low-energy use, both inherit energetic features from the passive-dynamic walkers on which they are based. By contrast, we estimate the state-of-the-art Honda humanoid Asimo to have cet , 3.2 and cmt , 1.6 (15). Thus Asimo, perhaps representative of joint-angle controlled robots, uses at least 10 times the energy (scaled) of a typical human” [311].

“The Cornell biped is specifically designed for minimal energy use. The primary energy losses for humans and robots walking at a constant speed are due to dissipation when a foot hits the ground and to active braking by the actuators (negative work). The Cornell design demonstrates that it is possible to completely avoid this negative actuator work. The only work done by the actuators is positive: The left ankle actively extends when triggered by the right foot hitting the ground, and vice versa. The hip joint is not powered, and the knee joints only have latches. The average mechanical power (10) of the two ankle joints is about 3 W, almost identical to the scaled gravitational power consumed by the passive-dynamic machine on which it is based (8). Including electronics, microcontroller, and actuators, the Cornell biped consumes 11 W (11)” [311].

Conclusion: Passive walking bipedal robots appear to meet all three criteria for selection. However, too much of the information comes from one source alone. More information from other sources should be included.

205 B.4 CALERA CEMENT

Field Biological Analogy Environmental Advantage Process Engineering Growth of reef coral Sequesters carbon

Company Competitor Life Cycle Phase Calera Corporation Portland cement Use

Biological Analogy Description “Ocean chemistry involves the gradual absorption and mineralization of carbon. Over geologic time, vast amounts of CO2 are naturally absorbed into the oceans and converted into stable minerals, such as limestone” [454]. “Limestone is a sedimentary rock composed primarily of calcium carbonate (CaCO3) in the form of the mineral calcite… Most limestones form in shallow, calm, warm marine waters. That type of environment is where organisms capable of forming calcium carbonate shells and skeletons can easily extract the needed ingredients from ocean water. When these animals die their shell and skeletal debris accumulate as a sediment that might be lithified into limestone. Their waste products can also contribute to the sediment mass. Limestones formed from this type of sediment are biological sedimentary rocks. Their biological origin is often revealed in the rock by the presence of fossils” [455]. If calcium carbonate (CaCO3) “is heated to a high temperature in a kiln the products will be a release of carbon dioxide gas (CO2) and calcium oxide (CaO)” [455].

“[M]arine cement…is produced by coral when making their shells and reefs, taking calcium and magnesium in seawater and using it to form carbonates at normal temperatures and pressures” [203]. According to Constantz: “Stony corals calcify by nucleation and growth of aragonite fibers on seed nuclei packets produced by the coral. Aragonite fibers arrange into polycrystalline bundles that lift the coral upward during fiber growth, entrapping fibrils and tissue sheets, from the undersurface of the calicoblastic epithelium, between growing crystals. The morphology and arrangement of the aragonite fibers are controlled by inorganic kinetic factors of crystal growth, akin to inorganically precipitated marine cements. Corals selectively plane- off extending fibers on completed structures and stop fiber growth. Similar skeletal construction and maintenance mechanisms are found in other phyla” [456].

Reef coral [285].

206 Bioinspired Design Description Calera has developed a cement-making process inspired by the mechanisms underlying growth of reef coral [285]. Calera cement “would capture and store carbon dioxide similarly to how coral absorb calcium and magnesium to build their shells” [457]. In the Calera process, “CO2 is mineralized in an aqueous precipitation process. CO2 reacts with calcium or magnesium in e.g. brines resulting in carbonates with can be used as a building material. Calera supposedly exhibits a CO2 capture efficiency of 70-90% with a good input conversion. It remains open to what degree these carbonates as the final product show cementitious properties” [458]. “The heart of the Calera process is the formation of novel, metastable calcium and magnesium carbonate and bicarbonate minerals, similar to those found in the skeletons of marine animals and plants, by capturing carbon dioxide from flue gas and converting the gas to stable solid minerals. These novel 'polymorphs' make it possible to produce high reactive cements without calcining the carbonate as is the case with conventional portland cement” [459].

Conversion of Carbon Dioxide to Carbonates [460].

Selection Criteria Verification #1: The design is truly bioinspired.

 “[I]n 1984, when Brent Constantz was a graduate student at the University of California at Santa Cruz” he studied “coral growth mechanisms in the Caribbean and the Indo-Pacific, as well as the deep sea and temperate latitudes. His insights about the physiochemically-dominated skeletogentic mechanism of reef coral led” him to become “interested in co-opting coral growth mechanisms for creating large structures in tropical oceans out of ‘mother-of-pearl’ or synthetic limestone. His vision was that these mechanisms would be lifted out of the sea in modules and assembled into massive structures in the built environment, like buildings and bridges… Constantz contacted Khosla in 2007 with his idea about a new ‘green cement’ to replace the carbon-intensive Portland cement, the third largest source of anthropogenic carbon dioxide. Khosla saw the value of the idea immediately and funded Calera... Within a few months, Constantz had assembled a team that was making carbonate cements from seawater, hauled 207 over from Santa Cruz to their facility in Los Gatos in a water trailer. In October 2007, while Khosla was visiting the Los Gatos laboratory, the team noted that lack of carbon dioxide in the seawater was limiting the reaction, and there was a need for more carbon dioxide. An experiment was in progress, bubbling carbon dioxide through the seawater, and it was noted that the yield increased eight-fold. Constantz turned to Khosla and asked, ‘Where can we get large quantities of carbon dioxide?’ ” [285].

 “Natural chemical processes in the world’s oceans inspire the Calera's technology. For millennia these processes have helped to balance the world’s carbon cycle and created massive formations of carbonate deposits, such as the white cliffs of Dover” [454].

#2: The design is feasible.  “Calera’s technology may be suitable for a variety of facilities, including both retrofits and new plants. We have successfully retrofitted our technology at the demonstration level to an existing gas plant in Moss Landing, California” [454].

 “Calera has conducted multi-pollutant testing with the process operated on flue gas from a wide variety of coals in the pilot scale plant” [461].

 “We have demonstrated the continuous operation at laboratory scale and have constructed a 1- ton per day pilot scale system at our facility in Moss Landing” [462].

 Currently, a demonstration plant exists at Moss Landing, CA, which uses flue gas from Dynegy’s Moss Landing natural gas facility [463]. According to Calera, the demonstration unit has been shown to capture 86% of the CO2 from the incoming flue gas, and similar capture percentages were also achieved from their “pilot size coal combustion test unit” [464].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  Calera cement, manufactured using flue gas from power plants, has potential to provide an environmentally sustainable alternative to standard types of cement and standard carbon capture and sequestration methods [465] because it sequesters CO2 from the flue gas and uses it to create valuable building materials [466].

 “Calera cement can potentially greatly reduce carbon dioxide emissions” [457].

Competitor Description “Cement is the most widely used building material, having a variety of applications in construction. It is characterized as a finely crushed, inorganic powder” [457]. “Calera cement can be used as a replacement for Portland cement” [203]. “The process for creating the most widely used cement, portland cement, is an energy intensive process, which consumes considerable natural resources, such as limestone. In addition, portland cement production releases harmful air pollutants, detrimental to human respiratory health, and also emits significant quantities of carbon dioxide” [457]. Sun et al. [457] detail the production process of Portland cement - from raw material processing, to clinker formation, to the crushing of clinker with additives to form Portland cement - and discuss related energy consumption and environmental impacts in each step.

208

White Portland Cement [467], and Portland Cement [468].

Comparison of Environmental Impact of BID and Competitor The production of cement has a large negative environmental impact.  “Cement, which is mostly commonly composed of calcium silicates, requires heating limestone and other ingredients to 2,640 degrees F (1,450 degrees C) by burning fossil fuels… Making one ton of cement results in the emission of roughly one ton of CO2- and in some cases much more” [203].  “Cement production emits a wide range of air pollutants (including nitrogen oxides, sulfur dioxides, and particulate matter (PM)) that affect human health (Marlowe and Mansfield 2002). Trace and toxic releases of hydrochloric acid, sulfuric acid, ammonia, heavy metals, and organic compounds are known to occur during cement production (US EPA 2006). Furthermore, cement production contributes to at least 5% of the global carbon dioxide emissions (Azios 2008)” [457].

Calera cement uses abundant materials, consumes pollutants, and generates valuable resources.  “Nor are there any limitations on the raw materials of the Calera cement: Seawater containing billions of tons of calcium and magnesium covers 70 percent of the planet and the 2,775 power plants in the U.S. alone pumped out 2.5 billion metric tons of CO2 in 2006. The process results in seawater that is stripped of calcium and magnesium—ideal for desalinization technologies—but safe to be dumped back into the ocean. And attaching the Calera process to the nation's more than 600 coal-fired power plants or even steel mills and other industrial sources is even more attractive as burning coal results in flue gas with as much as 150,000 parts per million of CO2” [203].

 “The heart of the Calera process is the formation of novel, metastable calcium and magnesium carbonate and bicarbonate minerals, similar to those found in the skeletons of marine animals and plants, by capturing carbon dioxide from flue gas and converting the gas to stable solid minerals. These novel 'polymorphs' make it possible to produce high reactive cements without calcining the carbonate as is the case with conventional portland cement.

“Akin to portland cement and aggregate which derive from mining operations in quarries and subsequent processing, the precise stoichiometry of Calera's cements will vary somewhat by site and will include other trace/minor components. In particular, many trace components will be captured from the flue gas such as sulfur oxides and mercury and will be incorporated into the solid phase as insoluble sulfates and carbonates. After removal from the water and appropriate processing, the solids have value in a number of construction applications” [459].

 “Calera supposedly exhibits a CO2 capture efficiency of 70-90% with a good input conversion. It remains open to what degree these carbonates as the final product show cementitious properties. The inventors claim the product to be carbon negative” [458].

209 Conclusion: A number of recent papers still refer to Calera cement in terms of investors’ beliefs, how much CO2 the cement “would capture” [457], and what impact there will be for Calera “if successful” [469], indicating Calera has not proven, at least publicly, that its process is effective and environmentally-beneficial. Additionally, the FAQ section of Calera’s website has questions such as “When can we expect to see an actual Calera cement?” and “What is the carbon footprint of your product?” [464]; Calera’s responses to these questions are vague. The carbon footprint question is answered with the statement, “The ultimate goal is to produce products that are carbon negative, and as we scale up and refine our technology, that remains at the forefront,” [464] meaning the design has not been finalized and it is not clear what the true environmental impact of this cement will be.

210 B.5 GECKEL

Field Biological Analogy Environmental Advantage Materials Science Geckos and mussels May not exist

Company Competitor Life Cycle Phase Northwestern University Uncertain None known

Biological Analogy Description Geckos and mussels have very different strategies for successfully attaching to objects in their environment. Geckos have the ability to rapidly stick to and detach from surfaces while they are moving [470,471], using hairlike attachment devices called setae [470,472]. Setae have a branching structure that ends with very thin foot hairs [294] on the order of 200 nm at the end of the branch [470]. Because of the adhesive properties of setae, geckos are able to stick to smooth surfaces [270,298] and walk up vertical surfaces and across ceilings [270,470-472]. However, geckos are unable to stick to wet surfaces [471].

In contrast, mussels are able to attach to surfaces underwater and are able to attach to almost any surface [21], “including classically adhesion-resistant materials” [473]. Additionally, surface adhesion in mussels occurs on a much longer time scale than geckos. Adhesion in muscles is intended to anchor the muscle in the intertidal zone so that it does not get washed out to sea or brought too far inland and broken on rocks [471]. This ‘anchor,’ called a byssus [21,474], is formed from a chemical glue secreted by the muscle surfaces [471,472].

Gecko Foot [475], and Mussel Adhesion [471].

Bioinspired Design Description Geckel is a nanoadhesive inspired by both the dry adhesive properties of geckos and the wet adhesive properties of mussels [298,470]. It is comprised of essentially “arrays of gecko-mimetic nanoscale pillars coated with a thin mussel-mimetic polymer film” [470]. A diagram of the fabrication process of geckel is shown in the figure below. Geckel can be used for a wide range of applications that require wet or dry temporary adhesives [470,476], such as securing “two wet sides of a cut tissue” in medicine [298]. Additionally, the attachment of geckel adhesive is reversible; after over 1000 cycles of contact and separation [298,470], there is only a 15% reduction in adhesion strength in water and a 2% reduction in air [472].

211

[470]

Selection Criteria Verification #1: The design is truly bioinspired.  A paper in Nature from Lee et al. explains the development of geckel: “We refer to the resulting flexible organic nanoadhesive as ‘geckel’, reflecting the inspiration from both gecko and mussel” [470].

 In a patent for geckel, Messersmith et al. state: “The present invention provides a unique ‘mimetic’ functional combination of the two unique natural adhesion mechanisms inspired by geckos and mussels” [472].

 Messersmith et al. also state: “Described herein is a new class of hybrid biologically-inspired adhesives comprising an array of nanofabricated polymer columnar pillars coated with a thin layer of a synthetic polymer that mimics the wet adhesive proteins found in mussel holdfasts… This hybrid adhesive, which combines the salient design elements of both gecko and mussel adhesives, provides a useful reversible attachment means for a variety of surfaces in many environments” [472].

#2: The design is feasible.  A prototype of geckel exists and the fabrication method is discussed thoroughly in Lee et al. [470]. While it is likely the manufacturing process would change substantially during large- scale manufacturing, the environmental impact in the other life cycle phases is likely to remain the same as is displayed in this prototype of geckel. 212  However, the authors refer to potential future improvements to the functionality of geckel: “Further refinement of the pillar geometry and spacing, the pillar material, and mussel-mimetic polymer may lead to even greater improvements in performance of this nanostructured adhesive” [470]. This suggests that the current prototype may not qualify as ‘fully functional’.  The Messersmith Research Group’s website for geckel states: “Our next step is to scale up the geckel adhesive for mass production, optimize the pillar geometry, and engineer mussel- mimetic polymers. We believe geckel adhesives will be used in many applications such as medical, industrial, and military settings in the future” [474].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  No information was found indicating a reduced environmental impact as a result of BID for Geckel.

Comparison of Environmental Impact of BID and Competitor The manufacturing of Geckel is explained below.  “E-beam lithography (eBL) was used to create an array of holes in a polymethyl methacrylate (PMMA) thin film supported on Silicon (Si) (PMMA/Si master). Casting of poly(dimethylsiloxane) (PDMS) onto the master followed by curing and lift-off resulted in gecko- mimetic nanopillar arrays. Finally, a mussel adhesive protein mimetic polymer is coated onto the fabricated nanopillars. The topmost organic layer contains catechols, a key component of wet adhesive proteins found in mussel holdfasts” [472].

The purpose of geckel is not to be more sustainable, but to provide a new function – allowing glues to adhere under water.  Messersmith says in an interview: “adhesion in a wet environment is very difficult to achieve. The simple fact that a mussel can attach to a wet surface that’s submerged underwater during adhesion is actually quite remarkable. There are very few man-made adhesives that work well under those conditions” [471].  The improved functionality of Geckel is also emphasized elsewhere: “Repetitive AFM measurements showed that geckel adhesive’s wet- and dry-adhesion power was only slightly diminished during many cycles of adhesion, maintaining 85% in wet (red) and 98% in dry (black) conditions after 1100 contact cycles (FIG.5). To our knowledge no other gecko-mimetic adhesive has demonstrated efficacy for more than a few contact cycles,2,8 and none have been shown to work under water” [472].

Conclusion: To be considered for analysis, sources indicating that Geckel has an environmental advantage as a result of its bioinspired feature would need to be identified.

213 B.6 HOTZONE RADIANT HEATER

Field Biological Analogy Environmental Advantage Mechanical Engineering Lobster eyes Unconfirmed

Company Competitor Life Cycle Phase Radiant Optics Standard radiant heater Use

Biological Analogy Description Lobster eyes, and the eyes of other long-bodied crustaceans of the suborder Macrura, have multiple radially-oriented square lenses [477-479], as can be seen in the figure below of the shrimp eye. These lenses act as mirrors and focus the light on “one or more photoreceptors” [298] so that the intensity of the light in the deep sea environment is amplified [298,477,479]. As a result of these box mirrors, “the eyes of shrimp and lobsters enjoy more than 250 times the light-catching power of the human eye” [479].

Shrimp eye [479], and Caribbean spiny lobster [480].

Bioinspired Design Description The HotZone radiant heater is an infrared spot heater that imitates the mirrored lenses found in the lobster eye to focus heat on a particular point, or to disburse it over a specified area. A patent for the radiant lenses describes the design in detail:  “[W]hen the face of the unit is disposed out of the plane…then the radiation undergoes a dispersing effect in the sense that the outgoing rays or lines of reflected radiation tend to diverge from the axis which intersects the face of the unit…Conversely, when the face of the unit is disposed below the focal plane… then the radiation undergoes a condensing effect in the sense that the outgoing rays or lines of reflected radiation tend to converge on the axis in question… Accordingly, by varying the location of the radiation face of the unit with respect to the focal plane of the panel, it is possible to vary the extent to which each unit of radiation undergoes superposition, that is, the extent to which each unit of radiation is imaged or “stacked” in the area to be heated, together with other units of radiation from the face of the radiation unit. This in turn, enables the designer to irradiate a specified work space in more or less intensified form than than the radiation source itself would provide by direct transmission to that space. For example, given a particular BTU per square foot rating… and a particular area… to be irradiated, the designer can 214 determine not only the best shape and size for the panel, but also the spatial relationship between the panel and the face of the unit which will provide the best level of heat in the space to be heated. Furthermore, since the designer is able to concentrate more heat within the space in question than was possible with a conventional heater having the same BTU per square foot rating, he can space the heater further above the work space to generate a ‘sun effect’ and eliminate the discomfort to personnel which occurs when the heater is disposed so close that they experience ‘swings’ in temperature as they move in an out of its image.

“A similar but opposite effect occurs in the eyes of crustaceans of the suborder Macrura, such as shrimp, crayfish and lobsters. They have compound mirror lens at the outer peripheries of their eyes.... They operate to ‘stack’ incoming light at points on the retina of the eyes of the crustaceans, so that the dim light which is commonly available to them in their natural habitat, is intensified for the purpose of their vision. Of course, the panel 10 uses this superposition effect to focus points of radiation on an area below the panel, whereas the lens of the eye of the crustacean uses it to intensify incoming light on the retina of the eye. However, in other applications of the invention, the panel 10 can be used to intensify bands of incoming light on points similar to the radiation points” [477].

Diagrams and photograph of the HotZone Radiant Heater [481,482].

Selection Criteria Verification #1: The design is truly bioinspired.  “Radiant Optics was founded in 1985… by inventor/entrepreneur Roger Johnson to capitalize on his lobster-eye inspired compound reflective lens that uniquely focuses and directs infrared energy… Johnson and his team developed and marketed a complete line of gas, then electric heaters, fitted with the patented IRLensTM to allow customers and partners to develop and implement highly energy efficient spot heating and thermal comfort solutions. Over the years, tens of thousands of HotZoneTM heaters have been sold… In 2008, Johnson exclusively licensed the assets of Radiant Optics to Schaefer Ventilation of Sauk Rapids, MN” [483].

 The Schaefer Ventilation Equipment website reads: “Welcome to the home of the HotZone® heater and the lobster eye-inspired IRLensTM” [484].

#2: The design is feasible.  “Over the years, tens of thousands of HotZoneTM heaters have been sold into factories, warehouses, arenas, stores and residences” [483].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.

No explicit claims regarding a reduced environmental impact of the heater were found during research on this design. However, the HotZone website (not peer-reviewed) does have a statement claiming an 215 environmental benefit of the heater. The HotZone website states:

[T]he patented lobster-eye IRLensTM… focuses three to five times more infrared energy into the center of the beam than heaters without lenses. This revolutionary design makes HotZone® the most energy-efficient infrared heater on the market… The revolutionary design of the IRLensTM captures the majority of the infrared wasted by ALL other heaters on the market and FOCUSES it on a targeted area or zone… As a result, the HotZone® can:  Increase delivered heat by 300-500%...  Reduce total heating costs by 50% or more.  Doesn’t heat areas that don’t need it. [484]

Additionally, a HotZone-related patent discusses how the performance of the reflectors is substantially reduced when they are hot: “For example, increasing the metal temperature of aluminum from 100 deg. F to 500 deg. F. may increase its absorption of certain wavelengths of radiant energy by up to a factor of about three to five” [481]. The patent goes on to discuss ways to reduce the temperature of the reflectors by “providing cooling air behind the reflector,” or:

by increasing the ability of the reflector surface that is exposed to the radiant energy to provide energy radiantly. In one example, this includes tailoring or modifying the reflector material’s emissivity to enhance reflection on the reflective (e.g., toward the radiant surface) or to enhance radiation from the reflector’s backside better (e.g., away from the radiant heater element’s surface). This may also be accomplished by designing the geometry of one or more of the reflectors [481].

It seems likely that changing the geometry of the reflectors, as mentioned in the last sentence, is the approach taken by HotZone and explains why the website claims the 300-500% increase in heat delivery with the associated reduction in heating costs.

Competitor Description The competitor in this case is a standard radiant heater without the boxy bioinspired lenses.

Comparison of Environmental Impact of BID and Competitor A HotZone-related patent argues that standard radiant heaters are not as efficient as claimed:

Radiant heaters convert gas, electric, or other non-radiant energy… into radiant energy. Other resulting non-radiant energy output (such as convective) diminishes heater efficiency. Other heater byproducts may contribute to air pollution. Existing radiant heaters have typically emphasized the primary radiant energy output. More particularly, they have typically disregarded the energy wasted by flue product gas… and by other convective gas flow... Electric radiant heater products typically claim to be 100% efficient on the grounds that all the input electricity is converted into some sort of heat. Gas radiant heater products (such as tube heaters, for example) typically claim very high efficiency on the grounds that the wasted flue product includes low unburned chemical energy. However, existing radiant heaters unnecessarily waste and amount of radiant energy equal to the convective heat gain in the ambient and/or flue products [481].

Conclusion: Although there may be reason to believe an environmental benefit exists as a result of the bioinspired feature, a peer-reviewed source is needed to confirm these suspected environmental benefits. 216 Appendix C: Design Library Designs Eliminated Using 3 Criteria

Information on 3 BIDs – Crystal Palace in London, the Eiffel Tower, and Velcro – is presented in Appendix C. The same format used for the designs in Appendix A was also intended to be used here. However, designs presented in Appendix C had were eliminated using at least one of the three criteria. Hence, a full analysis was not deemed necessary, and some sections are left blank.

217 C.1 CRYSTAL PALACE IN LONDON

Field Biological Analogy Environmental Advantage Architecture Uncertain – Possibly the Giant May not exist Water Lily

Biological Analogy Description

The Giant Water Lily [485,486].

DESIGN DESCRIPTION

The Crystal Palace [487,488].

Selection Criteria Verification #1: The design is truly bioinspired.

There are no firsthand accounts from Paxton, the designer of the Crystal Palace, indicating that his design was bioinspired. In addition, secondhand accounts are in disagreement on this issue, as is shown below.

 Phillip Ball, in his 2001 article in Nature, states that Paxton’s design for the Crystal Palace was inspired by “the ribbed stem of a lily leaf” [68]. Ball does not provide a citation for this statement.

 Ask Nature, a project of the Biomimicry Institute, has a website that agrees with Ball. It states that Paxton “mimicked the ribs and struts of the giant water-lily to provided the support needed” for the Crystal Palace [489]. This website does not contain a citation for this statement. 218

 However, another AskNature site explains the inspiring strategy behind the Crystal Palace and provides a quotation from Attenborough explaining Paxton’s process of bioinspiration [490]. Attenborough states that Paxton was both a gardener and an architect. He received one of the first seedlings from the Amazon water-lily to reach Europe when he was running the Duke of Devonshire’s gardens in the mid-19th century [491]. Paxton “built one of the first big glasshouses. When he came to design the cast-iron supports for his hithero unprecedented expanse of glass, he remembered the ribs and struts of his giant water-lily that supported gigantic leaves and used them as the basis of his designs not only for the glass-houses at Chatsworth but also, a few years later, for his architectural masterpiece, the Crystal Palace in London”[491]. As is typical of most books, Attenborough does not provide a reference to the primary source of this information.

 Vogel, on the contrary, uses the example of the Crystal Palace as one which shows how the idea of bioinspiration romanticized a design, even when the design was not truly bioinspired [116]. Vogel finds a speech from Paxton speaking of how a greenhouse he designed before the Crystal Palace was inspired by a leaf, but concludes that there is no evidence that the Crystal Palace was inspired by the giant water lily [116].

 Julian Vincent et al. cite Vogel’s analysis when discussing bioinspired systems which “may be apocryphal in their derivation, have the status of urban myth, or be the product of over- enthusiasm” [11].

#2: The design is feasible.  The Crystal Palace was constructed “in 1851 for the Great Exhibition held in London’s Hyde Park” [487].

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  There is no evidence of peer-reviewed documentation indicating that the potentially bioinspired features of the Crystal Palace are environmentally beneficial.

Conclusion: The Crystal Palace meets neither criterion #1 nor #3.

219 C.2 EIFFEL TOWER

Field Biological Analogy Environmental Advantage Architecture Uncertain – Possibly bone May not exist structure, trabecular struts in the head of a human femur, or the taper of a tulip stem

Biological Analogy Description

Tulip Stem [492]. Head of human femur [493].

DESIGN DESCRIPTION

Eiffel Tower [494].

Selection Criteria Verification #1: The design is truly bioinspired.

There are no firsthand accounts from Eiffel, the designer of the Eiffel Tower, indicating that his design was bioinspired. In addition, secondhand accounts are in disagreement on this issue. Philip Ball, in a 2001 article in Nature, states that the Eiffel Tower was inspired by bone structure [68]. Ball does not provide a citation for this statement. Julian Vincent et al., in a 2006 article in Journal of the Royal Society Interface, state that there are myths that the Eiffel Tower was inspired by the human femur or a 220 tulip stem, but that it was actually just designed to resist wind loading [11]. Vincent et al. also do not provide a citation for their statement. It is easy to see how two contradicting statements in white literature, which propagate through the literature through citations, may cause confusion. Ball’s statement, for instance, has been cited by Reap et al. in a 2005 IMECE article [28].

#2: The design is feasible. The Eiffel Tower was constructed in 1889 for the World’s Fair.

#3: The design has a reduced environmental impact as a result of its bioinspired feature. There is no evidence of peer-reviewed documentation indicating that the potentially bioinspired features of the Eiffel Tower are environmentally beneficial.

Conclusion: The Eiffel Tower meets neither criterion #1 nor #3.

221 C.3 VELCRO

Field Biological Analogy Environmental Advantage Mechanical Engineering Cockleburs May not exist

Company Competitor Life Cycle Phase Velcro, Inc. Buttons, zippers, shoelaces None

Biological Analogy Description Cockleburs disperse the seeds of plants. Because of their hooked structure that mechanically interlocks upon contact with fur or cloth, for example, burs are easily able to detach from their plant and attach to passers-by [495]. This hooked structure is visible in the magnified view below.

Cockleburs [496,497], and magnified hooks on fruit of C. lutetiana [495].

Bioinspired Design Description Velcro is widely used as a fastener; it is a “separable fastening device comprised of two elements” – one with loops, and the other with hooks that hold their shape [498]. “[W]hen two layers of this type are pressed into face to face relation a substantial percentage of hooks engage with one another, and the two layers are thus hooked one to the other. Separation requires a force of considerable magnitude when it is attempted to release a large number of hooks at once but separation may be quite readily effected by progressively peeling the layers apart” [498]. One of the first Velcro-related patents in the US states that Velcro is “adapted to be used… as closing devices for clothing, blinds or the like” [498]. Some other applications for Velcro include: shoes, roller skates, memo boards, coats, gloves, costumes, watches, Velcro walls, knee braces, and products for use in space.

222

Velcro [499,500].

Selection Criteria Verification #1: The design is truly bioinspired.  Velcro USA’s website tells the story of the bioinspiration for Velcro: “In the early 1940's, Swiss inventor George de Mestral went on a walk with his dog... Upon his return home, he noticed that his dog's coat and his pants were covered with cockleburrs. His inventor's curiosity led him to study the burrs under a microscope, where he discovered their natural hook-like shape. This was to become the basis for a unique, two-sided fastener - one side with stiff "hooks" like the burrs and the other side with the soft "loops" like the fabric of his pants. The result was VELCRO® brand hook and loop fasteners” [232].

#2: The design is feasible.  Velcro is a widely-available commercial product.

#3: The design has a reduced environmental impact as a result of its bioinspired feature.  Velcro is a very general fastening product with a wide range of applications. When compared to other temporary attachment devices – such as buttons, zippers, strings, and tape – there is no. logical or fundamental reason why Velcro would offer an environmental advantage as a result of its bioinspired features. There is no evidence in peer-reviewed literature that this is the case.

 In some texts, Velcro is mentioned as a more sustainable alternative to permanent attachment procedures – such as welding – because it promotes easy disassembly and allows for remanufacturing. An entry in the Encyclopedia of Production and Manufacturing Management recommends: “Replace screws, glues and welds with new two-way snap-fit or velcro fasteners. Taking apart a snap-fitted or Velcro-fitted product is easier, and requires less energy than taking apart a welded product” [501]. A conference working paper on design for disassembly, provides a list of ‘traditional’ disassembly methods “in order, from greatest to least disassemblability” [502]. The list is as follows: “velcro, collets, clips, slip fit, bolted, force fit, welded with same material and welded with another material or glued” [502].

Competitor Description One of the first Velcro-related patents in the US states that Velcro is intended to replace “slide fasteners, buttons and other attachments of this type, particularly when a flexible closure, which is invisible and can be opened easily, is desirable” [498]. The competitors for Velcro considered here are buttons, zippers, and shoelaces. These are all temporary attachment devices for clothing-related applications.

223

Buttons [503], Zipper/Slide Fastener [504], Shoelaces [505].

Comparison of Environmental Impact of BID and Competitor When compared to competing temporary attachment devices – such as buttons, zippers, shoelaces – there is no logical or fundamental reason why Velcro would offer an environmental advantage. All of these attachment devices already operate mechanically, using only human energy. Ostensibly, the only differences in use between these options and Velcro are: (1) the aesthetic appearance of the fastening device, as well as (2) the level of fine motor skills required in fastening and unfastening the device.

Any environmental impact differences would be unrelated to the bioinspired shape of the hooks and loops of Velcro, except for, perhaps, the manufacturing processes required to produce the hook and loops. Examples in the literature that cite Velcro as a more sustainable alternative to welding, for instance, are not citing the most common applications for Velcro, and their claims would hold true for a wide range of temporary attachment devices, not just those inspired by the hooks of the cocklebur.

Conclusion: Velcro does not meet criterion #3.

224 Appendix D: Green Design Guidelines Adapted From Telenko [61]

A. Ensure sustainability of resources by: 1. Specifying renewable and abundant resources 2. Specifying recyclable, or recycled materials, especially those within the company or for which a market exists or needs to be stimulated 3. Layering recycled and virgin material where virgin material is necessary 4. Exploiting unique properties of recycled materials 5. Employing common and remanufactured components across models 6. Specifying mutually compatible materials and fasteners for recycling 7. Specifying one type of material for the product and its subassemblies

B. Ensure healthy inputs and outputs by: 8. Installing protection against release of pollutants and hazardous substances 9. Specifying non-hazardous and otherwise environmentally “clean” substances, especially in regards to user health 10. Ensuring that wastes are water-based or biodegradable 11. Specifying the cleanest source of energy 12. Including labels and instructions for safe handling of toxic materials 13. Specifying clean production processes for the product and in selection of components 14. Concentrating toxic elements for easy removal and treatment

C. Ensure minimum use of resources in production and transportation phases by: 15. Replacing the functions and appeals of packaging through the product’s design 16. Employing folding, nesting or disassembly to distribute products in a compact state 17. Applying structural techniques and materials to minimize the total volume of material 18. Specifying lightweight materials and components 19. Specifying materials that do not require additional surface treatment of inks 20. Structuring the product to avoid rejects and minimize material waste in production 21. Minimizing the number of components 22. Specifying materials with low-intensity production and agriculture 23. Specifying clean, high-efficiency production processes 24. Employing as few manufacturing steps as possible

D. Ensure energy efficiency of resources during use by: 25. Implementing reusable supplies or ensuring the maximum usefulness of consumables 26. Implementing fail-safes against heat and material loss 27. Minimizing the volume and weight of parts and materials to which energy is transferred 28. Specifying best-in-class energy efficiency components 29. Implementing default power down for subsystems that are not in use 30. Ensuring rapid warm up and power down 31. Maximizing system efficiency for an entire range of real world conditions 32. Interconnecting available flows of energy and materials within the product or between the product and its environment

225 33. Incorporating part-load operation and permitting users to turn off systems in part or whole 34. Use feedback mechanisms to indicate how much energy or water is being consumed 35. Incorporating intuitive controls for resource-saving features 36. Incorporating features that prevent waste of materials by the user 37. Defaulting mechanisms to automatically reset the product to its most efficient setting

E. Ensure appropriate durability of the product and components by: 38. Reutilizing high-embedded energy components 39. Planning for on-going efficiency improvements 40. Improving aesthetics and functionality to ensure the aesthetic life is equal to the technical life 41. Ensuring minimal maintenance and minimizing failure modes in the product and its components 42. Specifying better materials, surface treatments, or structural arrangements to protect products from dirt, corrosion, and wear 43. Indicating on the product which parts are to be cleaned/maintained in a specific way 44. Making wear detectable 45. Allowing easy repair and upgrading, especially for components that experience rapid change 46. Requiring few service and inspection tools 47. Facilitating testing of components 48. Allowing for repetitive dis- and re- assembly

F. Ensure disassembly, separation, and purification by: 49. Indicating on the product how it should be opened and make access points obvious 50. Ensuring that joints and fasteners are easily accessible 51. Maintaining stability and part placement during disassembly 52. Minimizing the # and variety of joining elements 53. Ensuring that destructive disassembly techniques do not harm people or reusable components 54. Ensuring reusable parts can be cleaned easily and without damage 55. Ensuring that incompatible materials are easily separated 56. Making component interfaces simple and reversibly separable 57. Organizing in hierarchical modules by aesthetic, repair, and end-of-life protocol 58. Implementing reusable/swappable platforms, modules, and components 59. Condensing into a minimal # of parts 60. Specifying compatible adhesives, labels, surface coatings, pigments, etc. which do not interfere with cleaning 61. Employing one disassembly direction without reorientation 62. Specifying all joints so that they are separable by hand or only a few, simple tools 63. Minimizing the number and length of operations for detachment 64. Marking materials in moulds with types and reutilization protocol 65. Using a shallow or open structure for easy access to subassemblies

226 Appendix E: 128 Sources Analyzed in BID Benefits Study

Table 18: 128 Sources Analyzed in BID Benefits Study. The first 29 with an asterisk* provide an extended explanation of BID benefits.

# Source *1 [506] Chakrabarti, A. and L. H. Shu, 2010, “Biologically Inspired Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, pp. 453-454. *2 [12] Wilson, J. O. and D. Rosen, 2007, "Systematic Reverse Engineering of Biological Systems," IDETC/CIE 2007, Las Vegas, Nevada, DETC2007-35395. *3 [97] Nagel, J. K. S., R. B. Stone and D. A. McAdams, 2010, "Exploring the Use of Category and Scale to Scope a Biological Functional Model," IDETC/CIE2010, Montreal, Canada, DETC2010-28873. *4 [507] Coelho, D. A. and C. A. M. Versos, 2011, “A Comparative Analysis of Six Bionic Design Methods,” International Journal of Design Engineering, Vol. 4, No. 2, pp. 114-131. *5 [508] Vandevenne, D., P.-A. Verhaegen, S. Dewulf and J. R. Duflou, 2012, "Automatically Populating the Biomimicry Taxonomy for Scalable Systematic Biologically-Inspired Design," IDETC/CIE 2012, Chicago, IL, DETC2012-70928. *6 [509] Glier, M. W., J. Tsenn, J. S. Linsey and D. A. McAdams, 2012, "Evaluating the Directed Method for Bioinspired Design," IDETC/CIE 2012, Chicago, IL, DETC2012-71511. *7 [127] Bar-Cohen, Y., 2006, “Biomimetics - Using Nature to Inspire Human Innovation,” Bioinspiration and Biomimetics, Vol. 1, pp. P1-P12. *8 [86] Vincent, J. F. V. and D. L. Mann, 2002, “Systematic Technology Transfer from Biology to Engineering,” Philosophical Transactions of the Royal Society A, Vol. 360, pp. 159-173. *9 [13] Helms, M., A. Goel and S. Vattam, 2010, "The Effect of Functional Modeling on Understanding Complex Biological Systems," IDETC/CIE 2010, Montreal, Canada, DETC2010-28939. *10 [116] Vogel, S., 1998, Cats' Paws and Catapults: Mechanical Worlds of Nature and People, W.W. Norton & Company, New York. *11 [117] Solga, A., Z. Cerman, B. F. Striffler, M. Spaeth and W. Barthlott, 2007, “The Dream of Staying Clean: Lotus and Biomimetic Structures,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S126-S134. *12 [72] Bruck, H. A., A. L. Gershon, I. Golden, S. K. Gupta, L. S. G. Jr, E. B. Magrab and B. W. Spranklin, 2007, “Training Mechanical Engineering Students to Utilize Biological Inspiration During Product Development,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S198-S209. *13 [220] Otero, T., 2008, “Reactive Conducting Polymers as Actuating Sensors and Tactile Muscle,” Bioinspiration and Biomimetics, Vol. 3, No. 3, pp. 035004. *14 [510] Forbes, P., 2005, "Something New Under the Sun," The Gecko's Foot: Bio-inspiration: Engineering New Materials from Nature, W.W. Norton & Company, Inc., New York, NY, pp. 1-28. *15 [139] Gunderson, S. L. and R. C. Schiavone, 1995, "Microstructure of an Insect Cuticle and Applications to Advanced Composites," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 163-197. *16 [122] Frankel, R. B. and D. A. Bazylinski, 1995, "Structure and Function of Magnetosomes in Magnetotactic Bacteria," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 199-215. *17 [98] Trexler, M. and R. M. Deacon, 2012, "Artificial Senses and Organs: Natural Mechanisms and Biomimetic Devices," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 35-93. 227 Table 18, cont. *18 [239] Masselter, T., G. Bauer, F. Gallenmuller, T. Haushahn, S. Poppinga, C. Schmitt, R. Seidel, O. Speck, M. Thielen, T. Speck, W. Barthlott, P. Ditsche-Kuru, H. Immink, J. Bertling, N. Molders, A. Nellesen, M. Rechberger, F. Cichy, M. Gude, M. Hermann, K. Lunz, J. Knippers, J. Lienhard, S. Schleicher, R. Luchsinger, C. Mattheck, I. Tesari, M. Milwich, T. Stegmaier, C. Neinhuis and H. Schwager, 2012, "Biomimetic Products," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 377-429. *19 [229] Stachelberger, H., P. Gruber and I. C. Gebeshuber, 2011, "Biomimetics: Its Technological and Societal Potential," Biomimetics - Materials, Structures and Processes (P. Gruber, D. Bruckner, C. Hellmichet al, Eds.), Springer, New York. *20 [69] Bar-Cohen, Y., 2006, "Introduction to Biomimetics: The Wealth of Inventions in Nature as an Inspiration for Human Innovation," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 1-40. *21 [511] Gruber, P., D. Bruckner, C. Hellmich, H.-B. Schmiedmayer, H. Stachelberger and I. C. Gebeshuber, 2011, "Preface," Biomimetics - Materials, Structures, and Processes, Springer, New York. *22 [67] Nagel, R. L., P. A. Midha, A. Tinsley, R. B. Stone, D. A. McAdams and L. H. Shu, 2008, “Exploring the Use of Functional Models in Biomimetic Conceptual Design,” Journal of Mechanical Design, Vol. 130. *23 [512] Jenkins, C. H. M., 2005, "Preface," Compliant Structures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA. *24 [68] Ball, P., 2001, “Life's Lessons in Design,” Nature, Vol. 409, pp. 413-416. *25 [270] Allen, R., 2010, "Introduction," Bulletproof Feathers: How Science Uses Nature's Secrets to Design Cutting-Edge Technology (R. Allen, Ed.), The University of Chicago Press, Chicago, pp. 6-21. *26 [155] Hobaek, T. C., K. G. Leinan, H. P. Linaas and C. Thaulow, 2011, “Surface Nanoengineering Inspired by Evolution,” BioNanoScience, Vol. 1, No. 3, pp. 63-77. *27 [43] Raibeck, L., J. Reap and B. Bras, 2008, "Investigating Environmental Benefits of Biologically Inspired Self-Cleaning Surfaces," 15th CIRP International Conference on Life Cycle Engineering, Sydney, Australia. *28 [62] Wadia, A. P. and D. A. McAdams, 2010, "Developing Biomimetic Guidelines for the Highly Optimized and Robust Design of Complex Products or Their Counterparts," IDETC/CIE2010, Montreal, Canada, DETC2010-28708. *29 [119] Nagel, J. K. S., R. L. Nagel, R. B. Stone and D. A. McAdams, 2010, “Function-Based, Biologically Inspired Concept Generation,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, No. 04, pp. 521-535. 30 [156] Langella, C., 2006, "Hybrid Design. Encoding Biological Principles in Sustainable Design," Sustainable Consumption and Production: Opportunities and Challenges, Wuppertal, Germany. 31 [136] Richter, K. and I. Grunwald, 2010, "Bio-inspired Polyphenolic Adhesives for Medical and Technical Applications: Introduction," Biological Adhesive Systems: From Nature to Technical and Medical Application (J. v. Byern and I. Grunwald, Eds.), Springer- Verlang/Wien, Austria, pp. 201-202. 32 [513] Yang, H. T. Y., C.-H. Lin, D. Bridges, C. J. Randall and P. K. Hansma, 2010, “Bio-Inspired Passive Actuator Simulating an Abalone Shell Mechanism for Structural Control,” Smart Materials and Structures, Vol. 19, No. 10. 33 [70] Hambourger, M., G. F. Moore, D. M. Kramer, D. Gust, A. L. Moore and T. A. Moore, 2009, “Biology and Technology for Photochemical Fuel Production,” Chemical Society Reviews Vol. 38, No. 1, pp. 25-35.

228 Table 18, cont. 34 [152] Knippers, J. and T. Speck, 2012, “Design and Construction Principles in Nature and Architecture,” Bioinspiration and Biomimetics, Vol. 7, No. 1, pp. 015002. 35 [28] Reap, J., D. Baumeister and B. Bras, 2005, "Holism, Biomimicry and Sustainable Engineering," ASME IMECE, Orlando, Florida, IMECE2005-81343. 36 [11] Vincent, J. F. V., O. A. Bogatyreva, N. R. Bogatyrev, A. Bowyer and A.-K. Pahl, 2006, “Biomimetics: Its Practice and Theory,” Journal of the Royal Society Interface, Vol. 3, pp. 471-482. 37 [85] Vattam, S. S., M. E. Helms and A. K. Goel, 2010, “A Content Account of Creative Analogies in Biologically Inspired Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, No. 4, pp. 467-481. 38 [226] Bhushan, B., 2012, Biomimetics: Bioinspired Hierarchial-Structured Surfaces for Green Science and Technology, Springer, New York. 39 [514] Sartori, J., U. Pal and A. Chakrabarti, 2010, “A Methodology for Supporting "Transfer" in Biomimetic Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, pp. 483-505. 40 [14] Nagel, J. K., 2010, "Systematic Design of Biologically-Inspired Engineering Solutions," Mechanical Engineering, Oregon State University, 41 [245] Vattam, S. S. and A. K. Goel, 2011, "Foraging for Inspiration: Understanding and Supporting the Online Information Seeking Practices of Biologically Inspired Designers," ASME 2011 International Design Engineering Technical Conferences & Computeres and Information in Engineering Conference, Washington, DC, DETC2011-48238. 42 [228] Anastas, P. T. and J. C. Warner, 1998, "Future Trends in Green Chemistry," Green Chemistry: Theory and Practice, Oxford University Press, Oxford, pp. 115-119. 43 [188] Turney, T., 2009, "Future Materials and Performance," Technology, Design and Process Innovation in the Built Environment (P. Newton, K. Hampson and R. Drogemuller, Eds.), Taylor & Francis, New York, pp. 31-53. 44 [247 ] Shu, L. H., 2010, “A Natural-Language Approach to Biomimetic Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, No. 4, pp. 507- 519. 45 [114] Chiu, I. and L. H. Shu, 2007, “Biomimetic Design Through Natual Language Analysis to Facilitate Cross-Domain Information Retrieval,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 21, pp. 45-59. 46 [515] Tarascon, J.-M., 2008, “Towards Sustainable and Renewable Systems for Electrochemical Energy Storage,” ChemSUSChem, Vol. 1, No. 8-9, pp. 777-779. 47 [227] Vincent, J., 2009, “Biomimetics - A Review,” Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering and Medicine, Vol. 223, No. 8, pp. 919-939. 48 [115] Cheong, H., I. Chiu, L. H. Shu, R. B. Stone and D. A. McAdams, 2011, “Biologically Meaningful Keywords for Functional Terms of the Functional Basis,” Journal of Mechanical Design, Vol. 133, No. 2, pp. 021007-1. 49 [94] Ke, J., I. Chiu, J. S. Wallace and L. H. Shu, 2010, "Supporting Biomimetic Design by Embedding Metadata in Natural-Language Corpora," ASME IDETC/CIE 2010, Montreal, Canada, DETC2010-29057. 50 [24] Moore, A. L., D. Gust and T. A. Moore, 2007, “Bio-inspired Constructs for Sustainable Energy Production and Use,” L'Actualite Chimique, No. 308-309, pp. 50-56. 51 [234] Nagel, J. K. S., R. B. Stone and D. A. McAdams, 2010, "An Engineering-to-Biology Thesaurus for Engineering Design," ASME IDETC/CIE 2010, Montreal, Canada, DETC2010-28233. 52 [222] French, M., 1994, Invention and Evolution: Design in Nature and Engineering, Cambridge University Press, New York. 229 Table 18, cont. 53 [88] Cheong, H., I. Chiu and L. H. Shu, 2010, "Extraction and Transfer of Biological Analogies for Creative Concept Generation," IDETC/CIE 2010, Montreal, Canada, DETC2010-29006. 54 [230] Gruber, P., 2011, "Biomimetics in Architecture [Architekturbionik]," Biomimetics - Materials, Structures and Processes (P. Gruber, D. Bruckner, C. Hellmichet al, Eds.), Springer, New York, NY, pp. 127-148. 55 [516] Vincent, J. F. V., 2005, "Compliant Structures and Materials in Animals," Compliant Structures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA, pp. 3-20. 56 [217] Ennos, A. R., 2005, "Compliance in Plants," Compliant Stuctures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA, pp. 21-37. 57 [517] Jenkins, C. H. M., 2005, "Design of Compliant Structures," Compliant Structures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA, pp. 247-261. 58 [518] Glier, M. W., J. Tsenn, J. S. Linsey and D. A. McAdams, 2011, "Methods for Supporting Bioinspired Design," International Mechanical Engineering Congress & Exposition, Denver, Colorado, IMECE2011-63247. 59 [519] Meijer, K., J. C. Moreno and H. H. C. M. Savelberg, 2006, "Biological Mechanisms as Models for Mimicking: Sarcomere Design, Arrangement and Muscle Function," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 41-56. 60 [240] Lipson, H., 2006, "Evolutionary Robotics and Open-Ended Design Automation," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 129-153. 61 [118] Hanson, D., 2006, "Robotic Biomimesis of Intelligent Mobility, Manipulation, and Expression," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 177-200. 62 [520] Ummat, A., A. Dubey and C. Mavroidis, 2006, "Bio-Nanorobotics: A Field Inspired by Nature," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 201-227. 63 [106] Zhang, S., H. Yokoi and X. Zhao, 2006, "Molecular Design of Biological and Nano- Materials," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL pp. 229-242. 64 [219] Dennis, R. G. and H. Herr, 2006, "Engineered Muscle Actuators: Cells and Tissues," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 243-266. 65 [521] Bar-Cohen, Y., 2006, "Artificial Muscles Using Electroactive Polymer," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 267-290. 66 [522] Szema, R. and L. P. Lee, 2006, "Biologically Inspired Optical Systems," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 291-308. 67 [125] Nemat-Nasser, S., S. Nemat-Nasser, T. Plaisted, A. Starr and A. V. Amirkhizi, 2006, "Mulitfunctional Materials," Biomimetics: Biologically Inspired Technologies (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 309-340. 68 [523] Carlson, J., S. Ghaey, S. Moran, C. A. Tran and D. L. Kaplan, 2006, "Biological Materials in Engineering Mechanisms," Biomimetics:Biologically Inspired Technologies (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 365-379. 69 [103] Gorb, S. N., 2006, "Functional Surfaces in Biology: Mechanisms and Applications," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raon, FL, pp. 381-397. 230 Table 18, cont. 70 [524] Lou, Z., S. Hosoe and M. Ito, 2006, "Biomimetic and Biologically Inspired Control," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 399-425. 71 [329] Stahlberg, R. and M. Taya, 2006, "Nastic Structures: The Enacting and Mimicking of Plant Movements," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 473-493. 72 [104] Muller, R., J. Ma, Z. Yan, C. Grimm and W. Mio, 2011, "Bioinspiration from Biodiversity in Sensor Design," International Mechanical Engineering Congress & Exposition, Denver, Colorado, IMECE2011-64487. 73 [208] Wainwright, S. A., W. D. Biggs, J. D. Currey and J. M. Gosline, 1976, Mechanical Design in Organisms, John Wiley & Sons, Inc., New York. 74 [120] Harris, C. M., 2009, “Biomimetics of Human Movement: Functional or Aesthetic?,” Bioinspiration and Biomimetics, Vol. 4, No. 3, pp. 033001. 75 [525] Plamondon, N. and M. Nahon, 2009, “A Trajectory Tracking Controller for an Underwater Hexapod Vehicle,” Bioinspiration and Biomimetics, Vol. 4, No. 3, pp. 036005. 76 [231] Vogel, S., 2009, “Nosehouse: Heat-Conserving Ventilators Based on Nasal Counterflow Exchangers,” Bioinspiration and Biomimetics, Vol. 4, No. 4, pp. 046004. 77 [526] Armour, R., K. Paskins, A. Bowyer, J. Vincent and W. Megill, 2007, “Jumping Robots: A Biomimetic Solution to Locomotion Across Rough Terrain,” Bioinspiration and Biomimetics, Vol. 2, No. 3, pp. S65-S82. 78 [527] Dabiri, J. O., 2007, “Renewable Fluid Dynamic Energy Derived from Aquatic Animal Locomotion,” Bioinspiration and Biomimetics, Vol. 2, No. 3, pp. L1-L3. 79 [121] Abdel-Aal, H. A. and M. E. Mansori, 2011, "Chapter 4: Reptilian Skin as a Biomimetic Analogue for the Design of Deterministic " Biomimetics - Materials, Structures and Processes (P. Gruber, D. Bruckner, C. Hellmichet al, Eds.), Springer, New York, NY, pp. 51-79. 80 [101] Gorb, S. N., M. Sinha, A. Peressadko, K. A. Daltorio and R. D. Quinn, 2007, “Insects Did It First: A Micropatterned Adhesive Tape for Robotic Applications,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S117-S125. 81 [144] Helms, M., S. S. Vattam and A. K. Goel, 2009, “Biologically Inspired Design: Process and Products,” Design Studies, Vol. 30, No. 5, pp. 606-622. 82 [528] Gopal, V. and M. J. Z. Hartmann, 2007, “Using Hardware Models to Quantify Sensory Data Acquisition Across the Rat Vibrissal Array,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S135-S145. 83 [237] Muller, R. and R. Kuc, 2007, “Biosonar-Inspired Technology: Goals, Challenges and Insights,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S146-S161. 84 [213] Liu, C., 2007, “Micromachined Biomimetic Artificial Haircell Sensors,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S162-S169. 85 [529] Nakrani, S. and C. Tovey, 2007, “From Honeybees to Internet Servers: Biomimicry for Distributed Management of Internet Hosting Centers,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S182-S197. 86 [75] Nagel, J. K. S. and R. B. Stone, 2011, "A Systematic Approach to Biologically-Inspired Engineering Design," ASME 2011 International Design Engineering and Technical Conferences & Computers and Information in Engineering Conference, Washington, DC, DETC2011-47398. 87 [123] Beheshti, N. and A. C. Mcintosh, 2007, “The Bombardier Beetle and Its Use of a Pressure Relief Valve System to Deliver a Periodic Pulsed Spray,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. 57-64.

231 Table 18, cont. 88 [530] Margerie, E. d., J. Mouret, S. Doncieux and J.-A. Meyer, 2007, “Artificial Evolution of the Morphology and Kinematics in a Flapping-Wing Mini-UAV,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. 65-82. 89 [531] Bartol, I., M. Gordon, P. Webb, D. Weihs and M. Gharib, 2008, “Evidence of Self- Correcting Spiral Flows in Swimming Boxfishes,” Bioinspiration and Biomimetics, Vol. 3, No. 1, pp. 014001. 90 [225] Vargas, A., R. Mittal and H. Dong, 2008, “A Computational Study of the Aerodynamic Performance of a Dragonfly Wing Section Gliding in Flight,” 2008, Vol. 3, No. 2, pp. 026004. 91 [96] Glier, M. W., D. A. McAdams and J. S. Linsey, 2011, "Concepts in Biomimetic Design: Methods and Tools to Incorporate into a Biomimetic Design Course," ASME 2011 Design Engineering Technical Conferences & Computers and Information in Engineering Conference, Washington, DC, DETC2011-48571. 92 [532] Myrick, A., K.-C. Park, J. R. Hetling and T. C. Baker, 2008, “Real-Time Odor Discrimination Using a Bioelectronic Sensor Array Based on the Insect Electroantennogram,” Bioinspiration and Biomimetics, Vol. 3, No. 4, pp. 046006. 93 [201] Wainwright, S. A., 1995, "What We Can Learn from Soft Biomaterials and Structures," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 1-12. 94 [533] Sarikaya, M., J. Liu and I. A. Aksay, 1995, "Nacre: Properties, Crystallography, Morphology, and Formation," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 35-90. 95 [534] Mann, S., 1995, "Biomineralization, the Inorganic-Organic Interface, and Crystal Engineering," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 91-116. 96 [535] Calvert, P., 1995, "Biomimetic Ceramics and Hard Composites," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 145-161. 97 [82] Mak, T. W. and L. H. Shu, 2004, “Abstraction of Biological Analogies for Design,” CIRP Annals - Manufacturing Technology, Vol. 53, No. 1, pp. 117-120. 98 [71] Vincent, J. F. V., 2008, “Biomimetic Materials,” Journal of Materials Research, Vol. 23, No. 12, pp. 3140-3147. 99 [154] Bar-Cohen, Y., 2012, "Introduction: Nature as a Source of Inspiring Innovation," Biomimetics:Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 1-34. 100 [536] Vattam, S. S., M. Helms and A. K. Goel, 2010, "Biologically Inspired Design: A Macrocognitive Account," IDETC/CIE 2010, Montreal, Canada, DETC2010-28567. 101 [537] Potter, K. A., B. Gui and J. R. Capadona, 2012, "Biomimicry at the Cell-Material Interface," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 95-129. 102 [73] Rey, A. D., D. Pasini and Y. K. Murugesan, 2012, "Multiscale Modeling of Plant Cell Wall Architecture and Tissue Mechanics for Biomimetic Applications," Biomimetics: Nature- Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 131-168. 103 [202] Strange, D. G. T. and M. L. Oyen, 2012, "Biomimetic Composites," Biomimetics: Nature- Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 169-212. 104 [194] Wolpert, H. D., 2012, "Biological Optics," Biomimetics: Nature-Based Innovation (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 267-305. 105 [110] Lee, D. W., 2012, "Biomimicry of the Ultimate Optical Device - The Plant," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 307-330. 232 Table 18, cont. 106 [137] Yen, J., M. J. Weissburg, M. Helms and A. K. Goel, 2012, "Biologically Inspired Design: A Tool for Interdisciplinary Education," Biomimetics: Nature-Based Innovation (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 331-360. 107 [105] Barthelat, F., 2007, “Biomimetics for Next Generation Materials,” Philosophical Transactions of the Royal Society A, Vol. 365, No. 1861, pp. 2907-2919. 108 [111] Argunsah, H. and B. L. Davis, 2012, "Application of Biomimetics in the Design of Medical Devices," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 445-459. 109 [538] Fish, F. E., A. J. Smits, H. Haj-Hariri, H. Bart-Smith and T. Iwasaki, 2012, "Biomimetic Swimmer Inspired by the Manta Ray," Biomimetics: Nature-Based Innovation (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 495-523. 110 [124] Kulfan, B. M. and A. J. Colozza, 2012, "Biomimetics and Flying Technology," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 525-674. 111 [190] Bar-Cohen, Y., 2012, "Biomimetics - Reality, Challenges, and Outlook," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 693-714. 112 [539] Weiner, S. and P. Zaslansky, 2004, "Structure-Mechanical Function Relations in Bones and Death," Learning from Nature How to Design New Implantable Biomaterials: From Biomineralization Fundamentals to Biomimetic Materials and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. 3- 13. 113 [126] Leonor, I. B., H. S. Azevedo, I. Pahkuleva, A. L. Oliveira, C. M. Alves and R. L. Reis, 2004, "Learning from Nature How to Design Biomimetic Calcium-Phosphate Coatings," Learning from Nature How to Design New Implantable Biomaterials: From Biomineralization Fundamental to Biomimetic Materials and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, Vol. 171, pp. 123-150. 114 [540] Aizenberg, J. and G. Hendler, 2004, "Learning from Marine Creatures How to Design Micro-Lenses," Learning from Nature: How to Design New Implantable Biomaterials: From Biomineralization Fundamentals to Biomimetic Materials and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, Vol. 171, pp. 151-166. 115 [9] Wikipedia,2012, Biomimicry. 2012. 116 [541] Isaacson, A.,2009, Nature Inspiring Green Design for Planes, Train, Autos & More. Popular Mechanics. 117 [542] Freedman, M.,2010, Nature is the Model Factory. Newsweek. 118 [112] Gebeshuber, I. C., B. Y. Majlis and H. Stachelberger, 2009, “Tribology in Biology: Biomimetic Studies Across Dimensions and Across Fields,” International Journal of Mechanical and Materials Engineering, Vol. 4, No. 3, pp. 321-327. 119 [543] Offner, D. H., 1995, "Introduction to Design Homology," Design Homology: An Introduction to Bionics, David Offner, Urbana, Illinois, pp. 1-12. 120 [209] Paturi, F. R., 1976, "Chapter 16: Where Do We Go from Here?," Nature: Mother of Invention: The Engineering of Plant Life, Harper & Row, New York, NY, pp. 199-203. 121 [544] Reis, R. L., 2004, "Preface," Learning from Nature How to Design New Implantable Biomaterials: From Biomimeralization Fundamentals to Biomimetic Materials and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. xi-xiv.

233 Table 18, cont. 122 [74] Papanek, V., 1984, "Chapter 8: The Tree of Knowledge: Biological Prototypes in Design," Design for the Real World: Human Ecology and Social Change, Van Nostrand Reinhold, New York, pp. 186-214. 123 [21] Benyus, J. M., 1997, Biomimicry: Innovation Inspired by Nature, William Morrow and Company, Inc., New York. 124 [7] Wann, D., 1994, Biologic: Designing with Nature to Protect the Environment, Johnson Books, Boulder, Colorado. 125 [135] Ausubel, K., 2004, "Introduction," Nature's Operating Instructions: The True Biotechnologies (K. Ausubel and J. P. Harpignies, Eds.), Sierra Club Books, San Francisco. 126 [187] Benyus, J., 2004, "Biomimicry: What Would Nature Do Here?," Nature's Operating Instructions: The True Biotechnologies (K. Ausubel and J. P. Harpignies, Eds.), Sierra Club Books, San Francisco. 127 [113] Dickinson, M. H., 1999, “Bionics: Biological Insight into Mechanical Design,” PNAS: Proceedings of the National Academy of Sciences, Vol. 96, No. 25, pp. 14208-14209. 128 [246] Yen, J. and M. Weissburg, 2007, “Editorial: Perspectives on Biologically Inspired Design: Introduction to the Collected Contributions,” Bioinspiration and Biomimetics, Vol. 2, No. 4.

234 Appendix F: BIDs Found from Breadth and Depth Searches

Table 19: BIDs Found from Breadth and Depth Searches. Designs #1-95 were found using the breadth search; designs #96-194 were found using the depth search.

# Design Inspired By Sources 1 Dirt and water-repellent paint/coating Lotus leaf [11,269-271] 2 Boat hulls Dolphin skin [271,272] 3 Sonar/radar Echolocation of bats [271] 4 Medical ultrasound imaging Echolocation of bats [271] 5 Velcro Burs, burdock plant [11,269,271,273] 6 Horn-shaped, saw-tooth design for lumberjack Wood-burrowing beetle [271] blades 7 Road reflectors Cat eyes [271] 8 Temperature-adapting clothing Pinecone [271] 9 Morphing aircraft wings Birds [113,271] 10 Morphing aircraft skin Fish scales [271] 11 RFID tags read through water and on metal Wing structure of blue [271,314] morpho butterfly 12 Nanosensors to detect explosives Wing structure of butterflies [271] 13 Adhesives Gecko feet [11,269,271,273] 14 Eastgate Centre cooling system Termite mound [35,269,271,274] 15 UAVs Hummingbirds [271] 16 B.I.A.S. Biologically Inspired Acoustic Big brown bat [545] Systems 17 Baleen water filters Blue whale [284] 18 BioBASE mooring for wave energy devices Bull kelp [274,546] 19 BioFriend anti-microbial filter Human cells [547] 20 Adhesive tape Insect feet [548] 21 Medical adhesive Sandcastle worm [549] 22 Biolytix water filter Natural decomposition on a [275] river’s edge 23 Biomatrica Sample Matrix – stores biological Brine shrimp (sea monkeys) [550] samples without refrigeration 24 Biodegradable water-soluble polymers Oyster [551] 25 BioSTREAM tidal energy harvester Bluefin tuna [552] 26 Calera cement-making process Skeletons of marine animals [285,286] 27 Daimler-Chrysler bionic car - shape Boxfish [269,273,274,276] 28 Daimler-Chrysler bionic car - structure –SKO Initially, adaptive growth of [11,274,276,277] software trees; later bones 29 CAO Software Initially bones; later trees [274,276,277] 30 Capillary faucet energy harvester Coconuts [553] 31 Carbon dioxide-based plastics Plants [554] 32 ChromaFlair color-shifting paint Morpho butterfly [555] 33 Crystal Palace in London Giant water lily [11,68,291] 34 Dew bank bottle Namib desert beetle, bumpy [11,556] surface of the elytra of beetles 235 Table 19, cont. 35 Dyesol solar cells Photosynthesis [557] 36 Eco-machine wastewater treatment system Aquatic ecosystems [558] 37 FLOWE wind farm Fish [559] 38 Fog-catching materials Namib desert beetle [560] 39 Goateck traction hiking sole Mountain goats [561] 40 GreenShield fabric finish Morpho butterfly/lotus [562] 41 GROW Solar Ivy Leaves [563] 42 Heliotrope sun-tracking system for solar Flowers [564] panels 43 HotZone radiant heater, using IRLens Lobster eyes [287] 44 Humidity responsive silk fibers Spider [565] 45 Humidity sensor without electronics Hercules beetle [566] 46 i2 modular carpet Forest floor [278,279] 47 IntAct Labs, LLC biosensor Protein in mammalian ear [567] canals 48 Joinlox mechanical method of joining Clams and other shellfish [568] components 49 Kalundborg, Denmark Ecosystem symbiosis [274,569] 50 LOCUST visual collision detector Locusts swarms [570] 51 Self-cleaning clay roof Lotus, butterfly wings [571] 52 Self-cleaning Lotusan paint Lotus, butterfly wings [11,113,572] 53 Mechanically adaptive polymer Sea cucumber [573] nanocomposites 54 Medical implant coating Blue mussel [574] 55 Microfluidic silk assembly Spider [575] 56 Mincor TX TT self-cleaning textile coating Lotus [576] 57 Mirasol color electronic screens Morpho butterfly wings [273,289] 58 Morphotex structural colored fibers Morpho butterfly wings [254,577] 59 MothEye and MARAG anti-glare and anti- Eyes of nocturnal moths [578] reflective films 60 Nanosphere self-cleaning fabric Morpho butterfly wings [579] 61 ORNILUX glass that reduces bird collisions UV-reflective spider silk [580] 62 Pangolin backpack from recycled truck tubes Pangolin [581] 63 PAX water mixer Bull kelp [582] 64 PaxFan fans Bull kelp [583] 65 Phillips helmets with external membrane Human head [584] 66 Pipeline leak sealer Platelets [585] 67 Polar thermos cozy Polar bear [586] 68 Power Plastic solar cell Chlorophyll [587] 69 PureBond wood glue Blue mussel [588] 70 Self-cleaning fabric Doves [589] 71 Self-cleaning optical coatings Moth eyes and cicada wings [590] 72 Self-cleaning surface Spider hairs [591] 73 Sharklet antimicrobial surfaces Shark skin [269,280,281] 74 Shinkansen 500 series train - nose cone Kingfisher [254,269,277,282] 75 Shinkansen 500 series train - pantograph Owl [254,283] 76 Tunnel boring machine Shipworm [283] 77 Soil moving equipment Common earthworm [592] 236 Table 19, cont. 78 Solar water still and pump Tree [593] 79 Stabilitech vaccine stabilization technology Spikemoss [594] 80 Swiss Re headquarters building Sea sponge [595] 81 Sycamore ceiling fan Sycamore tree seed pod [596] 82 VitRIS and HydRIS vaccine stabilization Anhydrobiosis in plants, [597] technologies animals, and bacteria 83 Water-repellent ship coatings Water fern [598] 84 Flapping micro-aerial vehicles (MAVs) Insect flight [599] 85 Solar cells Apposition compound eyes [600] of some dipterans 86 Robots with compliant materials in Tobacco hornworm [319] locomotory system (soft robots) caterpillar (Manduca sexta) 87 Odor-detecting robots Moth behavior [601] 88 Robot that rights itself in midair Gecko [313] 89 Undulating robot that moves through air Snake [313] 90 UAVs that fly in updrafts Storks [313] 91 Micro-air vehicles Birds – hummingbird, [11,313] budgerigar 92 Robotic thorax Flies [313] 93 Micro-air vehicles with passive joints Seagulls [313] 94 Radio-controlled gliders Soaring ravens, turkey [313] vultures, seagulls, and pelicans 95 Robotic maple seed Maple seed [313] 96 Earth ceramics with nanopores to control Dirt in termite mounds [254] humidity 97 Tiny solar batteries Way leaves turn sunlight into [254] energy 98 Body armor African freshwater fish [254] Polypterus senegalus scales 99 Pacemaker Humpback whale heart [254] 100 JR Central’s N700 series Shinkansen Front end modeled after an [254] eagle’s outstretched wings 101 Suitewall silica coating for exterior tiles Snail shell’s self-cleaning [254] bumps 102 Australia’s Biosignal Ltd. Healthcare products Algae’s ability to block [254] bacteria’s signals 103 Cooling system in Council House 2 in Termite mound’s evaporative [274,602] Melbourne, Australia cooling from aquifer water 104 Solar energy cell technology Photosynthesis [274] 105 Carbon Sequestration method from CO2 Chemical processes in [274] Solutions mammals during respiration 106 Novomer carbon-based polymers used for Carbon sequestration in [274] building materials plants 107 Teatro del Agua- desalinization process in Namib desert beetle [274] Canary Islands by Grimshaw Architects 108 London’s Porticullis House Termite mounds [602] 109 Sharklet Marine boat hull coatings Shark skin [281] 237 Table 19, cont. 110 Sharklet Medical devices Shark skin [281] 111 Wind turbine blades Serrated fin of humpback [269] whale 112 Anti-counterfeit technology for bank notes, Iridescent colors of [269] passports, and credit cards Indonesian peacock butterfly 113 Leonardo da Vinci’s flying machines Birds [11,68] 114 Designing buildings from the roof down Bee and spider [11] 115 Henry Mitchell’s design of a pile made of Forms of seed vessels [11] cones that digs itself into the ground 116 Clement Ader’s steam powered aircraft (Eole) Bats wings [11] 117 Ignaz and Igo Etrich’s stable wing design Winged seed of Alsomitra [11] macrocarpa 118 Jeronimidis material that has glass fiber in Cellulose walls in wood, [11] resin matrix making it tough in impact wood in tension 119 Surface textures Lotus leaf [11] 120 Antireflective surfaces Insect eyes [11] 121 Antireflective surfaces Insect wings [11] 122 Antireflective surfaces Leaves of plants in the [11] understory of tropical rainforests 123 Antireflective polythene sheet for solar panels Insect eyes, wings, or plant [11] - 10% improvement in capture of light leaves 124 Robotic control systems Natural neural circuits [11] especially in insects 125 Camouflage - Hugh Cott (presumably animals) [11] 126 Motion camouflage (staying in same spot in Dragonfly [11] visual field) 127 Surfaces of earth-moving machinery (ploughs, Geometrically optimized [11] bulldozers) ridges and bumps on soil- moving animals 128 Hulls of sailing boats Vortices induces by ridges on [11] shark skin 129 Lining of pipes carrying liquid Vortices induces by ridges on [11] shark skin 130 Aircraft with a drag reduction of 5-10% Vortices induces by ridges on [11] shark skin 131 Aircraft wings with reduced drag, Airbus Divided wing tip of birds [11,288] A380 with wings of low aspect ratio (buzzard, vulture, eagle) 132 Underwater propellers with reduced drag Divided wing tip of birds [11] with wings of low aspect ratio (buzzard, vulture, eagle) 133 Twiddlefish submersibles by Nekton, Inc. Fins of fish [11] 134 Low-drag dirigibles Penguin [11] 135 Lightweight tensile structures in architecture Spider webs [11] (Frei Otto) 136 Eiffel Tower Trabecular struts in the head [11,68] of a human femur or the taper of a tulip stem 238 Table 19, cont. 137 Swimsuits Shark skin [11] 138 Entrance gate to world exposition in Paris in Radiolarians [68] 1900 139 Wright brothers’ plane Swooping vultures [68] 140 C. Culmann’s construction crane Bone [68] 141 Sonar system Dolphins [256,270] 142 Acoustic Pulses Bottlenose dolphins [256] 143 Robocane Ecolocation [270] 144 Fins on modern aircraft wings that improve “Fingers” on the wingtips of [270] airflow and reduce drag birds of prey 145 Flipper-type propulsion system for underwater Turtle [270] robot vehicle 146 Foot-powered propulsion unit for kayak Penguin [270] 147 DIDSON acoustic camera Ecolocation [270] 148 Finnisterre breathable warm waterproof textile Waterproof pelage of seals [270] for surfers and otters 149 Chronino humanoid robot Human [270] 150 Underwater robotic vehicles that cancel out Timing of fish tail strokes [270] departing vortices and jellyfish pulses to maximize energy recovery from vortices 151 Geckel Geckos and mussels [270] 152 Pelamis wave converter – Aguacadoura wave The redundant vertebral units [270] farm of snakes 153 Microelectrodes for brain implants that are Sea cucumber’s body states [270] stiff for insertion and then relax that vary in stiffness 154 Micromechanical systems on AUVs Lateral line of a fish- [270] mechanoreceptor system 155 Robot that flies like a bird from Festo Bird- lightweight seagull [603] 156 Convert carpet How nature would [279] manufacture a floor 157 Self-repairing concrete Skin [314] 158 Surfboard Humpback whale [314] 159 Less painful needles Mosquito [314] 160 Passive systems to collect and distribute Thorny devil [314] naturally chilled water 161 Antifouling coating Adhesives secreted by [272] muscles 162 Biomimetic polymer for antifouling – zosteric Eel grass [272] acid 163 Antifouling – covalently cross-linked gel Skin of pilot whale [272] 164 X ray telescope Shrimp/lobster eye [478] 165 Collimator for x-ray lithography Lobster eye lens [478] 166 Car Paint Scarab beetle [273] 167 Increased solar cell light capture Hawkmoth [273] 168 Airbus 320 Shark skin riblets [113,273] 169 Bipedal robots Humans [273] 170 Novel, motion producing devices Muscles [273] 239 Table 19, cont. 171 Enzyme activity preservation Diatom [273] 172 Filtration, biosensor filtration, imunoisolation Diatom [273] 173 Surface adhesion Flies [273] 174 Surface adhesion Spiders [273] 175 Evolutionary Computing, Genetic Algorithms DNA [273] 176 Camouflage Moths [273] 177 Micro air vehicles leading edge vortex Hawkmoth [273] 178 Microair vehicles wing design Hummingbird [273] 179 Hydroplane strut wave reduction Bat Toes (for catching fish) [273] 180 Hydroplane strut wave reduction Black Skimmer Mandible [273] 181 Human oscillatory propelled exoskeletons, Tuna, dolphins, seals [273] flippers, and submarines 182 Robo-Tuna Tuna, dolphins, seals [273] 183 Underwater sensing, target acquisition, Mottled sculpin (fish) [273] obstacle avoidance 184 Data storage and readout, medical diagnostics, Honeybee eye [273] surveillance, photography 185 Underwater plume tracing and source finding Moths, lobsters [273] 186 Robotic source tracking using chemotaxis and C. Elegans [273] c.elegans based on neural network 187 Fluidic lens Whale eye [273] 188 Hydrophobic surfaces Rose petals [604] 189 Wood glue without toxins - Columbia Forest Secretions mussels use to [290] Products cling to surfaces underwater 190 Self-Healing Pipelines – Brinker Technology Platelets [290] 191 Biosignal film that prevents bacteria from Seaweed [290] colonizing 192 Qualcomm Mirasol display Butterfly wings, peacocks [290] 193 Carbozyme flue scrubber, converts CO2 to Enzymes of mollusks [290] limestone powder 194 Norian SRS biomineral bone cement used in Physiochemically-dominated [285] orthopedic surgery skeletogentic mechanism of reef coral

240 Appendix G: Comparison of the Environmental Impact of BIDs and Competitors Using GDGs with Justification

Nine sustainable BIDs were compared to a functionally-equivalent standard product using the GDGs presented in Appendix D. The analysis is provided below. First, the guidelines met better by the BIDs than their non-bioinspired competitor are provided, followed by the guidelines met worse by the BID than their non-bioinspired competing product, if any, and the guidelines for which such an assessment is uncertain, or only valid in some limited scenarios.

G.1 BIOLYTIX

Table 20: The GDGs met better by Biolytix than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 1 Specifying renewable Biolytix uses solid waste in the system along with worms and and abundant resources insects to filter and treat wastewater. All these inputs are both renewable and abundant. In contrast, conventional septic systems require nonrenewable chemical inputs. 2 Specifying recyclable, or The Biolytix process uses recycled human waste to filter new recycled materials, wastewater. This does not occur in septic tanks. especially those within the company or for which a market exists or needs to be stimulated 4 Exploiting unique The Biolytix process uses recycled human waste to filter new properties of recycled wastewater. materials 9 Specifying non- Biolytix uses worms and insects to filter and treat wastewater. In hazardous and otherwise contrast, conventional septic systems require potentially environmentally "clean" hazardous chemical inputs for the disinfection process that substances, especially in creates toxic byproducts. regards to user health 10 Ensuring that wastes are Biolytix breaks down all waste and does not have the non- water-based or biodegradable sludge byproduct that a traditional septic tank biodegradable does. Additionally, Biolytix uses solid waste in the system along with worms and insects to filter and treat wastewater. In contrast, conventional septic systems require chemical inputs that are potentially not water-based or biodegradable. Presumably, the chemicals used would be harsh biocides – as their function is to kill all bacteria and pathogens in the waste. 18 Specifying lightweight Because of the way Biolytix is designed, it is more efficient at materials and filtering and treating waste than a septic system. Consequently, components for the same amount of filtration, a Biolytix system can be smaller than a septic system. This means the weight is minimized and less energy needs to be transferred to the system during transport of the system to the point of use.

241 Table 20, cont. 25 Implementing reusable Biolytix uses solid waste in the system along with worms and supplies or ensuring the insects – reusable supplies – to filter and treat wastewater. In maximum usefulness of contrast, conventional septic systems require chemical inputs consumables which cannot be reused. 28 Specifying best-in-class In terms of energy consumption, Biolytix is more efficient than a energy efficiency standard septic system. With Biolytix, a user can get the same components filtration output but with less energy input into aerating pumps to remove the sludge. 32 Interconnecting available The flow of waste material through the Biolytix filter is flows of energy and interconnected with the functioning of the product. As the waste materials within the is filtered, it becomes the humus, which then filters the next batch product or between the of waste. Additionally, the Biolytix filter itself – which is filled product and its with worms and insects – functions much as a miniature soil environment ecosystem, where the living organisms that are a part of the product are interconnected with the filtering and treatment functions to a greater extent than occurs in septic systems with anaerobic bacteria. 41 Ensuring minimal Unlike septic systems, Biolytix does not need to be maintained maintenance and regularly for sludge removal. minimizing failure modes in the product and its components

G.2 DAIMLER-CHRYSLER BIONIC CAR – SHAPE

Table 21: The GDGs met better by the shape of the bionic car than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 28 Specifying best-in-class The reduced drag of the bioinspired car results in fuel savings, energy efficiency compared to the same car with a standard shape. Consequently, components the bioinspired car uses less fuel to go the same distance as its nonbioinspired competitor, meaning it is more energy efficient.

242 G.3 DAIMLER-CHRYSLER BIONIC CAR – STRUCTURE

Table 22: The GDGs met better by the structure of the bionic car than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 17 Applying structural The SKO method allows for light-weighting by getting rid of techniques and materials unnecessary material. This method has reduced the frame weight to minimize the total by 30% [368]. volume of material 18 Specifying lightweight The bioinspired SKO method reduces the weight of the car’s materials and structure by 30% [41]. components

27 Minimizing the volume, The bioinspired SKO method reduces the weight of the car area and weight of parts frame. Since energy is transferred to the car frame in the process and materials to which of moving the car, the bioinspired frame minimizes the weight of energy is transferred parts and materials to which energy is transferred. 28 Specifying best-in-class The bioinspired SKO method reduces the weight of the car energy efficiency frame. Consequently, the bioinspired car uses less fuel to go the components same distance as its non-bioinspired competitor, meaning it is more energy efficient than its competitor.

243 G.4 EASTGATE CENTRE COOLING SYSTEM

Table 23: The GDGs met better by the Eastgate Centre’s cooling system than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 1 Specifying renewable Air circulation in Eastgate occurs as a result of the buoyancy and abundant resources properties of the air and the geometric design of the building, allowing for a substantial reduction in electricity consumption when compared to an industrial air conditioning unit. The buoyancy of air is both renewable and abundant, compared to the electricity needed to power an industrial air conditioner. 11 Specifying the cleanest Eastgate uses geometry and waste heat from buildings along with source of energy assisting fans instead of relying much more heavily on electricity from ‘unclean’ sources, such as coal. 28 Specifying best-in-class Eastgate Centre’s cooling output is the same as a hypothetical energy efficiency competing industrial air conditioner’s output. However, less components active energy, in the form of electricity, is needed in Eastgate Centre to achieve this output than would be required by an industrial air conditioner. Consequently, Eastgate Centre’s passive cooling system is more energy efficient than the competing industrial air conditioning system. 32 Interconnecting available The waste heat from Eastgate Centre drives thermosiphon flow. flows of energy and The higher velocity air at the top of the chimney drives the materials within the induced flow. These flows of hot and cool air between the product or between the cooling system and the atmosphere around the building produce product and its cooling. Consequently, Eastgate’s cooling system design environment successfully interconnects available flows of air within itself and between itself and its environment to produce cooling. In contrast, air conditioners typically are stand-alone units, not designed to take advantage of the physics of fluid flows outside of the system.

244 G.5 INTERFACE FLOR I2 ENTROPY CARPET

Table 24: The GDGs met better by Entropy carpet than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 5 Employing common and If each individual carpet or dye lot is viewed as its own model, remanufactured Entropy carpet is artistically designed to allow tiles to be used components across across models, extending the useful lifetimes of these carpet tiles models and avoiding the need for new tiles to be manufactured. Consequently, Entropy modular carpet meets the spirit of the guideline. 20 Structuring the product Entropy carpet is artistically designed so that dye aberrations on to avoid rejects and individual tiles are not noticed, reducing the scrap rates in minimize material waste production. in production 40 Improving aesthetics and This guideline is met better by the Entropy carpet design than the functionality to ensure competitor in two ways: (1) Stains on a carpet tile are less the aesthetic life is equal noticeable on entropy carpet, meaning it is less likely that a to the technical life stained tile would need to be replaced for aesthetic reasons, i.e. the aesthetic life of the individual tiles is extended to better meet the technical life of the tile. (2) If a stain is noticeable and a tile needs to be replaced, only the stained tile needs to be replaced with Entropy carpet, and the aesthetic quality of the carpet is maintained. In this case, the aesthetic life of the carpet is better maintained after a tile is replaced to better match the technical life of the carpet. 45 Allowing easy repair and Entropy carpet allows for easier repair/upgrading of worn or upgrading, especially for stained tiles than standard modular carpet because new Entropy components that tiles blend in better with worn tiles, maintaining the appearance experience rapid change and extending the life of the carpet. In the case of tiles with a standard design, more tiles might need to be replaced at once, so that the new tile would not stand out compared to the old tiles, or the general appearance of the carpet would be compromised, possibly resulting in a shorter overall lifetime of the carpet. Additionally, old and new standard tiles would need to be from the same dye lot and oriented according to nap. 58 Implementing Entropy carpet tiles are reusable/swappable carpet components. reusable/swappable Entropy tiles from different dye lots can be used together, in platforms, modules, and contrast to standard modular carpets where tiles from different components dye lots cannot be swapped.

245 Table 25: The GDGs Entropy tiles might meet better than standard carpet tiles in some scenarios.

GDG # Guideline Why Bioinspired Design Probably Meets Guideline Better 41 Ensuring minimal Carpet maintenance would most likely refer to cleaning the maintenance and carpet, but it could also refer to replacing tiles. Entropy carpet minimizing failure tiles are slightly faster to replace than standard carpet tiles modes in the product and because they do not need to be oriented according to nap its components orientation. Consequently, they could be viewed as slightly reducing the maintenance load compared to a standard carpet.

G.6 SELF-CLEANING TRANSPARENT THIN FILM

Table 26: The GDGs met better by the self-cleaning surface than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 1 Specifying renewable The self-cleaning film uses gravity and surface texture in place of and abundant resources added chemicals, water, and energy which would otherwise be needed to clean the product 9 Specifying non- Water mist is 'clean'. Trichloroethylene (the chemical cleaning hazardous and otherwise solvent in the industrially-cleaned scenario) causes cancer in environmentally "clean" animals and is linked to kidney and liver disease in humans substances, especially in [605]. regards to user health 11 Specifying the cleanest The self-cleaning surface uses gravity and the surface texture to source of energy clean, instead of electricity. 25 Implementing reusable The self-cleaning surface uses less water during cleaning in the supplies or ensuring the use phase than a standard surface cleaned using spray or maximum usefulness of ultrasonic aqueous cleaning methods. consumables 27 Minimizing the volume, With the self-cleaning surface in the use phase, less water is used area and weight of parts (volume/weight are minimized) and less energy consequently and materials to which needs to be transferred to these materials during the cleaning energy is transferred process. 28 Specifying best-in-class The same cleaning output is achieved by the self-cleaning surface energy efficiency with less active energy required than when a standard surface is components cleaned using spray or ultrasonic aqueous cleaning methods. 32 Interconnecting available The self-cleaning surface uses gravity and the texture of the flows of energy and surface coating, instead of pressurized water and chemicals, to materials within the reduce total energy and water consumption during cleaning. It product or between the thereby utilizes available energy from within the product to product and its perform cleaning. environment

246 Table 27: The GDGs met worse by the self-cleaning surface than by its competitor.

GDG # Guideline Why Competitor Design Meets Guideline Better 7 Specifying one type of The self-cleaning film must be applied to the original surface material for the product which is made of another type of material. In contrast, a standard and its subassemblies surface would be made of only one type of material. 19 Specifying materials that The self-cleaning film is itself a surface treatment of material. A do not require additional standard material would not have a thin film or required surface surface treatment or inks. treatment. 22 Specifying materials The self-cleaning film is currently produced from titanium with low-intensity acetylacetonate, aluminum acetylacetonate, boehmite, ethanol, production and and a water repellent agent [27]. A lot of energy is consumed in agriculture the production of these materials Raibeck, 2008 #26}. Ethanol, for instance, is well-known to be an energy- and water-intensive material. 24 Employing as few The self-cleaning thin film must be applied to the surface during manufacturing steps as manufacturing. For a standard surface, no application step is possible required. 55 Ensuring that The thin film and the glass surface probably cannot be recycled incompatible materials together. The self-cleaning thin film is unlikely to be easily are easily separated. separated from the surface of the part for recycling purposes, compared to a standard part where no separation is necessary.

Table 28: The GDGs that might be met better by the self-cleaning surface than by its competitor, but ambiguity exists.

GDG # Guideline Why Competitor Design Probably Meets Guideline Better 10 Ensuring that wastes are Tricloroethylene displays “very slow biodegradation” and water-based or contamination of groundwater and soil “can be a very serious biodegradable problem” [606]. However, if you are cleaning a non- biodegradable or non-water based substance off the part the waste will not be guaranteed to be water-based or biodegradable. Here, we consider the dirt on the part as an inherent part of the waste being removed.

247 G.7 SHARKLET ANTIMICROBIAL SURFACE

Table 29: The GDGs met better by Sharklet than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 9 Specifying non- Sharklet can be used in place of toxic and biocidal disinfectants hazardous and otherwise or cleaning agents like Clorox that could directly harm the health environmentally "clean" of the user, harm the health of the organisms that will contact the substances, especially in waste water, or contribute to the evolution of superbugs, which regards to user health are environmentally ‘bad’ when taking an instrumental view of the environment. 41 Ensuring minimal Sharklet ensures that cleaning-related maintenance is minimized. maintenance and Instead of cleaning bathroom surfaces daily or weekly minimizing failure (depending on the location), Sharklet surfaces can be cleaned less modes in the product and frequently, perhaps as infrequently as once every 90 days (the life its components of a Sharklet strip) as a result of its bioinspired topography. 42 Specifying better Sharklet protects the surface it is covering from bacteria by using materials, surface better structural arrangements of surface features that prevent treatments, or structural bacteria from adhering to – and growing on – the surface. arrangements to protect products from dirt, corrosion, and wear

Table 30: The GDGs where it is unclear whether Sharklet or its competitor is environmentally superior.

GDG # Guideline Why It is Unclear Which Design Meets Guideline Better 10 Ensuring that wastes are Sharklet still has to be cleaned with Clorox, just less, so the water-based or wastes from Clorox are equally water-based/biodegradable biodegradable during use. We have no information on whether Sharklet is water-based or biodegradable. This could be a way in which Sharklet is worse. 25 Implementing reusable In one sense, consumable Sharklet strips can be used to keep supplies or ensuring the surfaces clean longer than just Clorox, and consequently could be maximum usefulness of viewed as ‘ensuring maximum usefulness of consumables’. consumables However, this perspective may not be valid because the intent of this guideline is most likely to compare two different quantities of the same type of consumables. In the case of Sharklet, however, we are comparing the usefulness of two different types of consumables (a little Clorox with Sharklet strips vs. a lot of Clorox). This is an apples to oranges comparison, and the environmentally superior choice is unclear, but a significant difference as a result of the bioinspired feature is likely to exist.

248 G.8 SHINKANSEN 500 SERIES NOSE CONE

Table 31: The GDGs met better by the Shinkansen nose cone than by its competitor.

GDG # Guideline Why Bioinspired Design Meets Guideline Better 8 Installing protection The kingfisher-inspired nose cone is designed to minimize noise against release of pollution. pollutants and hazardous substances 28 Specifying best-in-class The reduced drag on the bioinspired nose cone results in energy efficiency electricity savings, compared to the nose cone on the 300 Series components Shinkansen. Consequently, the 500 Series train with the bioinspired nose cone uses less fuel to go the same distance as its nonbioinspired competitor, meaning it is more energy efficient.

G.9 SHINKANSEN 500 SERIES PANTOGRAPH

Table 32: The GDGs met better by the Shinkansen pantograph than by its competitor.

GDG # Guideline Why Bioinspired Design Probably Meets Guideline Better 8 Installing protection The owl feather-inspired pantograph is designed to minimize against release of noise pollution. pollutants and hazardous substances 28 Specifying best-in-class The reduced drag on the bioinspired pantograph results in energy efficiency electricity savings, compared to the same pantograph with a components standard shape. Consequently, the train with the bioinspired pantograph uses less fuel to go the same distance as its nonbioinspired competitor, meaning it is more energy efficient.

249 Appendix H: Analysis of 9 Sustainable BIDs for Passive Mechanisms, Multifunctional Designs, and Optimized Geometries

Nine sustainable BIDs were analyzed to identify passive mechanisms, multifunctional designs, and optimized geometries. Justification for each determination of whether the keyword trend was present is provided for each design, along with relevant quotations from other sources, in particular Wadia [63]., which support this analysis.

H.1 BIOLYTIX

Table 33: Keyword Trends Analysis for Biolytix.

Keyword Trend Justification Trend Present? Passive Yes The Biolytix system filters and treats domestic waste water and solid Mechanisms organic waste [293,356] passively [297], with “passive ventilation” and the “passive transport” of waste through the system [296]. This occurs without active cleaning of the filtration device [296] or the use of active chemical inputs [360,361]. It uses gravity to transport material and the renewable bioenergy in worms and insects to provide ventilation. Multifunctional No There is no reason to believe that Biolytix has multifunctional Designs characteristics as a result of its bioinspired feature. Optimized No The decomposition process in nature is being mimicked, not any particular Geometries geometry.

H.2 DAIMLER-CHRYSLER BIONIC CAR – SHAPE

Table 34: Keyword Trends Analysis for the Shape of the Bionic Car.

Keyword Trend Justification Trend Present? Passive No The shape of the bionic car does not use passive energy sources to perform Mechanisms a function. Multifunctional No There is no reason to believe that the shape of the bionic car has Designs multifunctional characteristics as a result of its bioinspired feature. Optimized Yes The streamlined shape of the car was inspired by the boxfish. Due in part to Geometries its bioinspired shape, the air drag coefficient of the bionic car is 0.19, which indicates that the car is exceptionally aerodynamic [41] compared to the BMW 3 Series, which has a drag coefficient of 0.27 [369]. This consequently reduces fuel consumption. The boxfish is a stable and energy efficient swimmer because of the desirable vortices formed along its body during swimming [39,40]. The optimized geometry was transferred from biology to engineering, presumably with slight modifications. Wadia agrees: “The shape of the car is optimized to reduce air drag coefficient leading to higher efficiency” [63].

250 H.3 DAIMLER-CHRYSLER BIONIC CAR – STRUCTURE

Table 35: Keyword Trends Analysis for the Structure of the Bionic Car.

Keyword Trend Justification Trend Present? Passive No The structure of the bionic car does not use passive energy sources to Mechanisms perform a function. Multifunctional No There is no reason to believe that the structure of the bionic car has Designs multifunctional characteristics as a result of its bioinspired feature. Optimized No The structure of the bionic concept car is not inspired by a biological Geometries geometry, but by a process of putting material in highly stressed areas, i.e. an optimized structure. This structure does not directly imitate the structure in bones, but the process of developing the optimized structure in the car mimics the process of developing the optimized structure in bones.

H.4 EASTGATE CENTRE COOLING SYSTEM

Table 36: Keyword Trends Analysis for Eastgate Centre’s Cooling System.

Keyword Trend Justification Trend Present? Passive Yes The cooling system in Eastgate Centre is classified as passive in Mechanisms architectural literature [31] because the layout of the building promotes the rise of hot air through the chimneys and away from the building’s inhabitants [34]. This cooling is fueled by the physical properties of fluid flow and the structure of the building, eliminating the need for energy- intensive air conditioning and reducing the energy consumption of the building by approximately 50% [32]. An active cooling system would be a traditional industrial air conditioner. Wadia agrees: “The concrete floors serve as an energy source (passive cooling: thermal energy exchange with air drawn from the exterior) in the termite mound inspired Eastgate Building” [63]. Multifunctional Yes Eastgate integrates the structure of the building with the building’s cooling Designs system, eliminating the need for an industrial air conditioner. The design of Eastgate’s cooling system “incorporates a number of air shafts and voids, integral with the structure which allows cool air to enter the building at its base and warm air to discharge at roof level” [32]. Wadia agrees that integration occurs in Eastgate Centre: “The Eastgate Complex integrates the internal and external environments reducing the chances of system failure” [63]. Optimized No Eastgate imitates the fluid flow in termite mounds, allowing for heat to rise Geometries and cool air to enter the way termite mounds do. This is related to mimicking the structure of termite mounds through chimneys, not mimicking the actual geometry of the termite mounds.

251 H.5 INTERFACE FLOR I2 ENTROPY CARPET

Table 37: Keyword Trends Analysis for Entropy Carpet.

Keyword Trend Justification Trend Present? Passive No The artistic design of the carpet tiles does not use passive inputs to perform Mechanisms a function. Multifunctional No There is no sense in which two components or systems are integrated in the Designs aesthetic design of the carpet that were not also integrated in the competing design. Optimized No The design of the bioinspired carpet tiles mimics color schemes and the Geometries random visual pattern found on forest floors, not a shape or geometry.

H.6 SELF-CLEANING TRANSPARENT THIN FILM

Table 38: Keyword Trends Analysis for the Self-Cleaning Surface.

Keyword Trend Justification Trend Present? Passive Yes Gravity and the surface texture of the self-cleaning transparent thin film are Mechanisms the inputs that allow cleaning to occur more passively than spray or ultrasonic aqueous cleaning methods. While self-cleaning surfaces still require a mist of water to be introduced, the cleaning process itself is more passive than in alternative cleaning options; cleaning here happens with less active energy and in response to the existing chemical conditions inherent in the coating, instead of in response to the active dissolution of dirt particles and the action of the pressurized water pushing the particles off the surface. Multifunctional Yes The surface of the part itself and the cleaning mechanism are integrated in Designs the self-cleaning transparent thin film, allowing for the elimination of additional cleaning modules. Liu and Jiang [328] discuss the lotus leaf as an example of “biological materials with function integration,” saying that it “Superhydrophobicity, low adhesion” and “self-cleaning” functions. Optimized No The surface texture of the self-cleaning thin film allows water to bead up Geometries because the contact angle is high. However, this texture does not mimic the actual geometry of the lotus leaf.

252 H.7 SHARKLET ANTIMICROBIAL SURFACE

Table 39: Keyword Trends Analysis for Sharklet Antimicrobial.

Keyword Trend Justification Trend Present? Passive No Sharklet antimicrobial surface prevents bacteria growth through their shape. Mechanisms However, the prevention of bacteria growth is not the same as containing a mechanism for passive cleaning. Hence, Sharklet antimicrobial surface does not contain a passive mechanism. This result may confusing to those knowledgeable about Sharklet because Sharklet marine is described as having a passive cleaning mechanism. According to one of the Sharklet patents: “it has been proven through experimental testing that surface topographies according to the invention provide a passive and nontoxic surface, which through selection of appropriate feature sizes and spacing, can significantly… reduce settlement and adhesion of the most common marine algae known, as well as the settlement of barnacles” [266]. Sharklet marine would act as a self-cleaning surface and would be passive for the same reasons the self-cleaning transparent thin film is, but Sharklet antimicrobial is not. Multifunctional No Sharklet antimicrobial is a bacteria-prevention module separate from the Designs door or surface where it would be applied. It is an additional module added to the door and cleaning systems. While it reduces the amount of Clorox required for cleaning, it is not multifunctional compared to the standard door and cleaning system and does not reduce the number of modules or components the system requires. Optimized Yes Sharklet antimicrobial surfaces have geometries inspired by shark skin that Geometries are optimized to prevent bioadhesion [396,266]. According to one of the Sharklet patents: “the geometric shape and arrangement of individual features of Sharklet was likely critical because it enhanced anti-settlement effectiveness over topographies of equivalent dimensions” [266]. This message is echoed in another Sharklet patent as well [396].

H.8 SHINKANSEN 500 SERIES NOSE CONE

Table 40: Keyword Trends Analysis for the Shinkansen 500 Series Nose Cone.

Keyword Trend Justification Trend Present? Passive No The geometry of the nose cone does not use passive inputs to perform a Mechanisms function. Multifunctional No There is no sense in which components have been integrated in the Designs bioinspired design to produce more functional parts. Optimized Yes The geometry of the kingfisher was transferred to the nose cone, making it Geometries more aerodynamic, reducing drag, and ultimately saving energy. Wadia agrees: “The nose’s optimized shape manipulates air flowing over it to reduce air pressure accumulation” [63].

253 H.9 SHINKANSEN 500 SERIES PANTOGRAPH

Table 41: Keyword Trends Analysis for the Shinkansen 500 Series Pantograph.

Keyword Trend Justification Trend Present? Passive No The pantograph serrations do not use passive inputs to perform a function. Mechanisms Multifunctional No There is no sense in which components have been integrated in the Designs bioinspired design to produce more functional parts. Optimized Yes The serrations on owl's feathers are mimicked geometrically in the Geometries Shinkansen's pantograph. Wadia agrees: “The shape of the edges on the pantograph is optimized to create smaller vortices in the airflow that in turn help with noise regulation” [63]

254 References

[1]Schick, K. D. and N. Toth, 1993, Making Silent Stones Speak: Human Evolution and the Dawn of Technology, Simon & Schuster, New York.

[2]May, R. M., J. H. Lawton and N. E. Stork, 1995, "Assessing Extinction Rates," Extinction Rates (J. H. Lawton and R. M. May, Eds.), Oxford University Press, Oxford, pp. 1-24.

[3]Lodge, D. and K. Shrader-Frechette, 2003, “Nonindigenous Species: Ecological Explanation, Environmental Ethics, and Public Policy,” Conservation Biology, Vol. 17, No. 1, pp. 31-37.

[4]EPA, 1999, Considering Ecological Processes in Envionmental Impact Assessments, United States Environmental Protection Agency (US EPA) Office of Federal Activities.

[5]Chapin III, F. S., E. S. Zavaleta, V. T. Eviner, R. L. Naylor, P. M. Vitousek, H. L. Reynolds, D. U. Hooper, S. Lavorel, O. E. Sala, S. E. Hobbie, M. C. Mack and S. Diaz, 2000, “Consequences of Changing Biodiversity,” Nature, Vol. 405, pp. 234-242.

[6]The Earth Charter Initiative,2000, The Earth Charter.

[7]Wann, D., 1994, Biologic: Designing with Nature to Protect the Environment, Johnson Books, Boulder, Colorado.

[8]Jones, C. G., J. H. Lawton and M. Shachak, 1994, “Organisms as Ecosystem Engineers,” Oikos, Vol. 69, No. 3, pp. 373-386.

[9]Wikipedia,2012, Biomimicry. 2012, http://en.wikipedia.org/wiki/Biomimicry.

[10]Wikipedia,2012, Bionics. 2012, http://en.wikipedia.org/wiki/Bionics.

[11]Vincent, J. F. V., O. A. Bogatyreva, N. R. Bogatyrev, A. Bowyer and A.-K. Pahl, 2006, “Biomimetics: Its Practice and Theory,” Journal of the Royal Society Interface, Vol. 3, pp. 471-482.

[12]Wilson, J. O. and D. Rosen, 2007, "Systematic Reverse Engineering of Biological Systems," IDETC/CIE 2007, Las Vegas, Nevada, DETC2007-35395.

255 [13]Helms, M., A. Goel and S. Vattam, 2010, "The Effect of Functional Modeling on Understanding Complex Biological Systems," IDETC/CIE 2010, Montreal, Canada, DETC2010-28939.

[14]Nagel, J. K., 2010, "Systematic Design of Biologically-Inspired Engineering Solutions," Mechanical Engineering, Oregon State University,

[15]Vollrath, F. and D. P. Knight, 2001, “Liquid Crystalline Spinning of Spider Silk,” Nature, Vol. 410, pp. 541-548.

[16]Dabiri, J. O., S. P. Colin and J. H. Costello, 2006, “Fast-swimming Hydromedusae Exploit Velar Kinematics to Form an Optimal Vortex Wake,” The Journal of Experimental Biology, Vol. 209, pp. 2025-2033.

[17]Barthlott, W. and C. Neinhuis, 1997, “Purity of the Sacred Lotus, or Escape from Contamination in Biological Surfaces,” Planta, Vol. 202, pp. 1-8.

[18]Raschi, W. and C. Tabit, 1992, “Functional Aspects of Placoid Scales: A Review and Update,” Australian Journal of Marine and Freshwater Research, Vol. 43, pp. 123-147.

[19]North Shore City Government, ,Environmental Education. 2013, http://www2.northshorecity.govt.nz/our_environment/Environmental_education/S hopping_default.htm.

[20]Davies, C., 2006, Robot Gecko Wind Time Approval. 2013, http://www.slashgear.com/robot-gecko-wins-time-approval- 072397/#entrycontent.

[21]Benyus, J. M., 1997, Biomimicry: Innovation Inspired by Nature, William Morrow and Company, Inc., New York.

[22]Earthsky.org,2011, Biomimicry Offers Sustainable Solutions Inspired by Nature, Fast Company. 2012, http://www.fastcompany.com/1734291/biomimicry-offers- sustainable-solutions-inspired-by-nature.

[23]Merchant, B.,2011, How Biomimicry Drives Sustainability: From Fish-Inspired Wind Turbines to the Future of 3-D Printing, Treehugger.com. 2012, http://www.treehugger.com/clean-technology/how-biomimicry-drives- sustainability-from-fish-inspired-wind-turbines-to-the-future-of-3-d-printing- video.html.

256 [24]Moore, A. L., D. Gust and T. A. Moore, 2007, “Bio-inspired Constructs for Sustainable Energy Production and Use,” L'Actualite Chimique, No. 308-309, pp. 50-56.

[25]Faure, E., P. Lecomte, S. Lenoir, C. Vreuls, C. V. D. Weerdt, C. Archambeau, J. Martial, C. Jerome, A.-S. Duwez and C. Detrembleur, 2011, “Sustainable and Bio-inspired Chemistry for Robust Antibacterial Activity of Stainless Steel,” Journal of Materials Chemistry, Vol. 21, pp. 7901-7904.

[26]Evans, M.,2012, What is Biomimicry? Design Emulating Nature, About.com. 2012, http://sustainability.about.com/od/GreenBuilding/a/What-Is-Biomimicry.htm.

[27]Raibeck, L., J. Reap and B. Bras, 2008, "Life Cycle Inventory Study of Biologically Inspired Self-Cleaning Surfaces," ASME IDETC/CIE 2008, Brooklyn, New York, DETC2008-49848.

[28]Reap, J., D. Baumeister and B. Bras, 2005, "Holism, Biomimicry and Sustainable Engineering," ASME IMECE, Orlando, Florida, IMECE2005-81343.

[29]Jones, D. L., 1998, Architecture and the Environment: Bioclimatic Building Design, The Overlook Press, Woodstock, New York.

[30]Baird, G., 2001 The Architectural Expression of Environmental Controls, Spon Press, New York.

[31]Thomas, D., 2002, Architecture and the Urban Environment: A Vision for the New Age, Architectural Press, Woburn, Massachusetts.

[32]Chown, M., 2003, "Building Simulation as an Aide to Design," Eighth International IBPSA Conference, Eindhoven, Netherlands.

[33]Curriculum Vitae: Mick Pearce, Architects for Peace. 2011, http://www.architectsforpeace.org/mickprofile.php.

[34]Turner, J. S. and R. C. Soar, 2008, "Beyond Biomimicry: What Termites Can Tell Us About Realizing the Living Building," First International Conference on Industrialized, Intelligent Construction (I3CON), Loughborough University.

[35]Biomimicry Institute,2010, Eastgate Centre Building, Ask Nature. 2010, http://www.asknature.org/product/373ec79cd6dba791bc00ed32203706a1.

[36]California Air-Conditioning Systems, Inc. Lomita, CA. 2013, http://www.californiaac.com/. 257

[37]Patterson, M.,2009, Eastgate Center, Ask Nature, http://www.asknature.org/product/373ec79cd6dba791bc00ed32203706a1#change Tab.

[38]Ask Nature,2013, Eastgate Centre Building. 2013, http://www.asknature.org/browse.

[39]Bartol, I. K., M. Gharib, P. W. Webb, D. Weihs and M. S. Gordon, 2005, “Body- Induced Vortical Flows: A Common Mechanism for Self-Corrective Trimming Control in Boxfishes,” The Journal of Experimental Biology, Vol. 208, pp. 327- 344.

[40]Choi, J.-g. and M. Kim, 2009, "The Usage and Evaluation of Anthropomorphic Form in Robot Design," Undisciplined!: Design Research Society Conference, Sheffield, United Kingdom.

[41]Thomer, K. W., 2007, "Materials and Concepts in Body Construction," Automotive Paintings and Coatings (H.-J. Streitberger and K.-F. Dossel, Eds.), Wiley-VCH, Weinheim, Germany, pp. 23-25.

[42]Nakajima, A., K. Hashimoto, T. Watanabe, K. Takai, G. Yamauchi and A. Fujishima, 2000, “Transparent Superhydrophobic Thin Films with Self-Cleaning Properties,” Langmuir, Vol. 16, pp. 7044-7047.

[43]Raibeck, L., J. Reap and B. Bras, 2008, "Investigating Environmental Benefits of Biologically Inspired Self-Cleaning Surfaces," 15th CIRP International Conference on Life Cycle Engineering, Sydney, Australia.

[44]Srivathsan, A.,2006, Smart Materials and Self-Cleaning Bathrooms. The Hindu, http://www.hindu.com/pp/2006/06/03/stories/2006060300360300.htm.

[45]2012, Ask Nature. 2012, http://www.asknature.org/strategy/714e970954253ace485ab f1cee376ad8.

[46]ISO, ,2006, ISO 14040: Environmental Management - Life Cycle Assessment - Principles and Framework, 2nd Edition. Geneva, Switzerland.

[47]ISO, 2007,"ISO Standards for Life Cycle Assessment to Promote Sustainable Development," 2011, http://www.iso.org/iso/pressrelease.htm?refid=Ref1019.

[48]ISO.,2006, ISO 14044: Environmental Management - Life Cycle Assessment - Requirements and Guidelines. Geneva, Switzerland.

258 [49]Reap, J., F. Roman, S. Duncan and B. Bras, 2008, “A Survey of Unresolved Problems in Life Cycle Assessment: Part 1: Goal and Scope and Inventory Analysis,” International Journal of Life Cycle Assessment, Vol. 13, pp. 290-300.

[50]Finnveden, G., 2000, “On the Limitations of Life Cycle Assessment and Environmental Systems Analysis Tools in General,” International Journal of Life Cycle Assessment, Vol. 5, No. 4, pp. 229-238.

[51]Jolliet, O., R. Muller-Wenk, J. Bare, A. Brent, M. Goedkoop, R. Heijungs, N. Itsubo, C. Pena, D. Pennington, J. Potting, G. Rebitzer, M. Stewart, H. U. d. Haes and B. Weidema, 2004, “The LCIA Midpoint-Damage Framework of the UNEP/SETAC Life Cycle Initiative,” International Journal of Life Cycle Assessment, Vol. 9, No. 6, pp. 394-404.

[52]Nash, R. F., 1989, The Rights of Nature: A History of Environmental Ethics, The University of Wisconsin Press, Madison, WI.

[53]Brennan, A. and Y.-S. Lo, 2011, "Environmental Ethics," Stanford Encyclopedia of Philosophy (E. N. Zalta, Ed.).

[54]United Nations, 1992, Convention on Biological Diversity. 2012, http://www.cbd.int/convention/text/.

[55]United Nations,1992, Report of the United Nations Conference on Environment and Development: Rio Declaration on Environment and Development. Rio de Janeiro. 2012.

[56]UNESCO,1997, Declaration on the Responsibilities of the Present Generations Towards Future Generations. Paris, UNESCO: Culture of Peace Programme.

[57]Millet, D., L. Bistangnino, C. Lanzavecchia, R. Camous and T. Poldma, 2007, “Does the potential of the use of LCA match the team design needs?,” Journal of Cleaner Production, Vol. 15, pp. 335-346.

[58]Lewis, H. and J. Gertsakis, 2001, Design + Environment: A Global Guide to Designing Greener Goods, Greenleaf Publishing Limited, Sheffield.

[59]Sroufe, R., S. Curkovic, F. Montabon and S. A. Melnyk, 2000, “The New Product Design Process and Design for Environment: Crossing the Chasm,” International Journal of Operations and Production Management, Vol. 20, No. 2, pp. 267-291.

[60]Bhamra, T. A., S. Evans, T. C. McAloone, M. Simon, S. Poole and A. Sweatman, 1999, "Integrating Environmental Decisions into the Product Development 259 Process: Part1 The Early Stages," First International Symposium on Environmentally Conscious Design and Inverse Manufacturing, Tokyo, IEEE.

[61]Telenko, C., 2009, "Developing Green Design Guidelines: A Formal Method and Case Study," MS Thesis,Mechanical Engineering, University of Texas at Austin, Austin, Texas.

[62]Wadia, A. P. and D. A. McAdams, 2010, "Developing Biomimetic Guidelines for the Highly Optimized and Robust Design of Complex Products or Their Counterparts," IDETC/CIE2010, Montreal, Canada, DETC2010-28708.

[63]Wadia, A. P., 2011, "Developing Biomimetic Design Principles for the Highly Optimized and Robust Design of Products or Their Components," Mechanical Engineering, Texas A&M University,

[64]Biomimicry Guild, 2009, Life's Principles, http://osbsustainablefuture.org/home/ section-newsletter/20101spring6isleleitch/.

[65]Biomimicry Group,2011, Life's Principles, http://bouncingideas.files.wordpress.com/ 2012/01/lifes-principles.png.

[66]Biomimicry 3.8, 2012, Frequently Answered Q's. 2013, http://biomimicry.net/about/biomimicry38/frequently-answered-qs/#faq12.

[67]Nagel, R. L., P. A. Midha, A. Tinsley, R. B. Stone, D. A. McAdams and L. H. Shu, 2008, “Exploring the Use of Functional Models in Biomimetic Conceptual Design,” Journal of Mechanical Design, Vol. 130.

[68]Ball, P., 2001, “Life's Lessons in Design,” Nature, Vol. 409, pp. 413-416.

[69]Bar-Cohen, Y., 2006, "Introduction to Biomimetics: The Wealth of Inventions in Nature as an Inspiration for Human Innovation," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 1- 40.

[70]Hambourger, M., G. F. Moore, D. M. Kramer, D. Gust, A. L. Moore and T. A. Moore, 2009, “Biology and Technology for Photochemical Fuel Production,” Chemical Society Reviews Vol. 38, No. 1, pp. 25-35.

[71]Vincent, J. F. V., 2008, “Biomimetic Materials,” Journal of Materials Research, Vol. 23, No. 12, pp. 3140-3147.

260 [72]Bruck, H. A., A. L. Gershon, I. Golden, S. K. Gupta, L. S. G. Jr, E. B. Magrab and B. W. Spranklin, 2007, “Training Mechanical Engineering Students to Utilize Biological Inspiration During Product Development,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S198-S209.

[73]Rey, A. D., D. Pasini and Y. K. Murugesan, 2012, "Multiscale Modeling of Plant Cell Wall Architecture and Tissue Mechanics for Biomimetic Applications," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 131-168.

[74]Papanek, V., 1984, "Chapter 8: The Tree of Knowledge: Biological Prototypes in Design," Design for the Real World: Human Ecology and Social Change, Van Nostrand Reinhold, New York, pp. 186-214.

[75]Nagel, J. K. S. and R. B. Stone, 2011, "A Systematic Approach to Biologically- Inspired Engineering Design," ASME 2011 International Design Engineering and Technical Conferences & Computers and Information in Engineering Conference, Washington, DC, DETC2011-47398.

[76]Markman, A. B. and K. L. Wood, 2009, "The Cognitive Science of Innovation Tools," Tools for Innovation (A. B. Markman and K. L. Wood, Eds.), Oxford University Press, New York, NY, pp. 3-22.

[77]Shah, J. J., N. Vargas-Hernandez and S. M. Smith, 2003, “Metrics for Measuring Ideation Effectiveness,” Design Studies, Vol. 24, pp. 111-134.

[78]Oman, S. K., I. Y. Tumer, K. Wood and C. Seepersad, 2012, “A Comparison of Creativity and Innovation Metrics and Sample Validation Through In-Class Design Projects,” Research in Engineering Design, pp. DOI 10.1007/s00163-012- 0138-9.

[79]Boden, M. A., 2004, The Creative Mind: Myths and Mechanisms, Routledge, London.

[80]Wilson, J. O., D. Rosen, B. A. Nelson and J. Yen, 2010, “The Effects of Biological Examples in Idea Generation,” Design Studies, Vol. 31, No. 2, pp. 169-186.

[81]Casakin, H. and G. Goldschmidt, 1999, “Expertise and the Use of Visual Analogy: Implications for Design Education,” Design Studies, Vol. 20, pp. 153-175.

[82]Mak, T. W. and L. H. Shu, 2004, “Abstraction of Biological Analogies for Design,” CIRP Annals - Manufacturing Technology, Vol. 53, No. 1, pp. 117-120.

261 [83]Chan, J., K. Fu, C. Schunn, J. Cagan, K. Wood and K. Kotovsky, 2011, “On the Benefits and Pitfalls of Analogies for Innovative Design: Ideation Performance Based on Analogical Distance, Commonness, and Modality of Examples,” Journal of Mechanical Design, Vol. 133, No. 8, pp. 081004-1

[84]Lopez, R., J. S. Linsey and S. M. Smith, 2011, "Characterizing the Effect of Domain Distance in Design-by-analogy," ASME 2011 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference, Washington, DC, DETC2011-48428.

[85]Vattam, S. S., M. E. Helms and A. K. Goel, 2010, “A Content Account of Creative Analogies in Biologically Inspired Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, No. 4, pp. 467-481.

[86]Vincent, J. F. V. and D. L. Mann, 2002, “Systematic Technology Transfer from Biology to Engineering,” Philosophical Transactions of the Royal Society A, Vol. 360, pp. 159-173.

[87]Price, S.,2000, Audacious & Outrageous: Space Elevators. Science News. T. Phillips, National Aeronautics and Space Administration (NASA). 2012, http://science.nasa.gov/science-news/science-at-nasa/2000/ast07sep_1/.

[88]Cheong, H., I. Chiu and L. H. Shu, 2010, "Extraction and Transfer of Biological Analogies for Creative Concept Generation," IDETC/CIE 2010, Montreal, Canada, DETC2010-29006.

[89]Mak, T. W. and L. H. Shu, 2004, "Use of Biological Phenomena in Design by Analogy," ASME 2004 Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Salt Lake City, Utah, USA, DETC2004-57303.

[90]Mak, T. W. and L. H. Shu, 2008, “Using Descriptions of Biological Phenomena for Idea Generation,” Research in Engineering Design, Vol. 19, pp. 21-28.

[91]Dahl, D. W. and P. Moreau, 2002, “The Influence and Value of Analogical Thinking During New Product Ideation,” Journal of Marketing Research, Vol. 39, No. 1, pp. 47-60.

[92]Benami, O. and Y. Jin, 2002, "Creative Stimulation in Conceptual Design," ASME 2002 Design Engineering Technical Conferences and Computer and Information in Engineering Conference, Montreal, Canada, DETC2002/DTM-34023.

262 [93]Christensen, B. T. and C. D. Schunn, 2007, “The Relationship of Analogical Distance to Analogical Function and Preinventive Structure: The Case of Engineering Design,” Memory & Cognition, Vol. 35, No. 1, pp. 29-38.

[94]Ke, J., I. Chiu, J. S. Wallace and L. H. Shu, 2010, "Supporting Biomimetic Design by Embedding Metadata in Natural-Language Corpora," ASME IDETC/CIE 2010, Montreal, Canada, DETC2010-29057.

[95]Fu, K., J. Chan, J. Cagan, K. Kotovsky, C. Schunn and K. Wood, 2012, "The Meaning of 'Near' and 'Far': The Impact of Structuring Design Databases and the Effect of Distance of Analogy on Design Output," IDECTC/CIE 2012, Chicago, IL.

[96]Glier, M. W., D. A. McAdams and J. S. Linsey, 2011, "Concepts in Biomimetic Design: Methods and Tools to Incorporate into a Biomimetic Design Course," ASME 2011 Design Engineering Technical Conferences & Computers and Information in Engineering Conference, Washington, DC, DETC2011-48571.

[97]Nagel, J. K. S., R. B. Stone and D. A. McAdams, 2010, "Exploring the Use of Category and Scale to Scope a Biological Functional Model," IDETC/CIE2010, Montreal, Canada, DETC2010-28873.

[98]Trexler, M. and R. M. Deacon, 2012, "Artificial Senses and Organs: Natural Mechanisms and Biomimetic Devices," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 35-93.

[99]Sadava, D., H. C. Heller, G. H. Orians, W. K. Purves and D. M. Hillis, 2008, Life: The Science of Biology, Sinauer Associates, Inc., Sunderland, MA.

[100]Basalla, G., 1988, "Chapter 1: Diversity, Necessity, and Evolution," The Evolution of Technology (G. Basalla and W. Coleman, Eds.), Cambridge University Press, Cambridge, United Kingdom.

[101]Gorb, S. N., M. Sinha, A. Peressadko, K. A. Daltorio and R. D. Quinn, 2007, “Insects Did It First: A Micropatterned Adhesive Tape for Robotic Applications,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S117-S125.

[102]World Intellectual Property Organization, 2012, WIPO IP Statistics Data Center. Geneva, Switzerland, United Nations. 2013, http://ipstatsdb.wipo.org/ipstats/patentsSearch.

263 [103]Gorb, S. N., 2006, "Functional Surfaces in Biology: Mechanisms and Applications," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raon, FL, pp. 381-397.

[104]Muller, R., J. Ma, Z. Yan, C. Grimm and W. Mio, 2011, "Bioinspiration from Biodiversity in Sensor Design," International Mechanical Engineering Congress & Exposition, Denver, Colorado, IMECE2011-64487.

[105]Barthelat, F., 2007, “Biomimetics for Next Generation Materials,” Philosophical Transactions of the Royal Society A, Vol. 365, No. 1861, pp. 2907-2919.

[106]Zhang, S., H. Yokoi and X. Zhao, 2006, "Molecular Design of Biological and Nano-Materials," Biomimetics: Biologically Inspired Technologies (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL pp. 229-242.

[107]Thomas, D. N. and G. S. Dieckmann, 2002, “Antartic Sea Ice - A Habitat for Extremophiles,” Science, Vol. 295, pp. 641-644.

[108]Stetter, K. O., 1999, “Extremophiles and Their Adaptation to Hot Environments,” FEBS Letters, Vol. 452, pp. 22-25.

[109]Nies, D. H., 2000, “Heavy Metal-Resistant Bacteria as Extremophiles: Molecular Physiology and Biotechnological Use of Ralstonia sp. CH34,” Extremophiles, Vol. 4, pp. 77-82.

[110]Lee, D. W., 2012, "Biomimicry of the Ultimate Optical Device - The Plant," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 307-330.

[111]Argunsah, H. and B. L. Davis, 2012, "Application of Biomimetics in the Design of Medical Devices," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 445-459.

[112]Gebeshuber, I. C., B. Y. Majlis and H. Stachelberger, 2009, “Tribology in Biology: Biomimetic Studies Across Dimensions and Across Fields,” International Journal of Mechanical and Materials Engineering, Vol. 4, No. 3, pp. 321-327.

[113]Dickinson, M. H., 1999, “Bionics: Biological Insight into Mechanical Design,” PNAS: Proceedings of the National Academy of Sciences, Vol. 96, No. 25, pp. 14208-14209.

[114]Chiu, I. and L. H. Shu, 2007, “Biomimetic Design Through Natual Language Analysis to Facilitate Cross-Domain Information Retrieval,” Artificial 264 Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 21, pp. 45-59.

[115]Cheong, H., I. Chiu, L. H. Shu, R. B. Stone and D. A. McAdams, 2011, “Biologically Meaningful Keywords for Functional Terms of the Functional Basis,” Journal of Mechanical Design, Vol. 133, No. 2, pp. 021007-1.

[116]Vogel, S., 1998, Cats' Paws and Catapults: Mechanical Worlds of Nature and People, W.W. Norton & Company, New York.

[117]Solga, A., Z. Cerman, B. F. Striffler, M. Spaeth and W. Barthlott, 2007, “The Dream of Staying Clean: Lotus and Biomimetic Structures,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S126-S134.

[118]Hanson, D., 2006, "Robotic Biomimesis of Intelligent Mobility, Manipulation, and Expression," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 177-200.

[119]Nagel, J. K. S., R. L. Nagel, R. B. Stone and D. A. McAdams, 2010, “Function- Based, Biologically Inspired Concept Generation,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, No. 04, pp. 521-535.

[120]Harris, C. M., 2009, “Biomimetics of Human Movement: Functional or Aesthetic?,” Bioinspiration and Biomimetics, Vol. 4, No. 3, pp. 033001.

[121]Abdel-Aal, H. A. and M. E. Mansori, 2011, "Chapter 4: Reptilian Skin as a Biomimetic Analogue for the Design of Deterministic " Biomimetics - Materials, Structures and Processes (P. Gruber, D. Bruckner, C. Hellmichet al, Eds.), Springer, New York, NY, pp. 51-79.

[122]Frankel, R. B. and D. A. Bazylinski, 1995, "Structure and Function of Magnetosomes in Magnetotactic Bacteria," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 199-215.

[123]Beheshti, N. and A. C. Mcintosh, 2007, “The Bombardier Beetle and Its Use of a Pressure Relief Valve System to Deliver a Periodic Pulsed Spray,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. 57-64.

[124]Kulfan, B. M. and A. J. Colozza, 2012, "Biomimetics and Flying Technology," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 525-674.

265 [125]Nemat-Nasser, S., S. Nemat-Nasser, T. Plaisted, A. Starr and A. V. Amirkhizi, 2006, "Mulitfunctional Materials," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 309-340.

[126]Leonor, I. B., H. S. Azevedo, I. Pahkuleva, A. L. Oliveira, C. M. Alves and R. L. Reis, 2004, "Learning from Nature How to Design Biomimetic Calcium- Phosphate Coatings," Learning from Nature How to Design New Implantable Biomaterials: From Biomineralization Fundamental to Biomimetic Materials and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, Vol. 171, pp. 123-150.

[127]Bar-Cohen, Y., 2006, “Biomimetics - Using Nature to Inspire Human Innovation,” Bioinspiration and Biomimetics, Vol. 1, pp. P1-P12.

[128]Fong, D. W., T. C. Kane and D. C. Culver, 1995, “Vestigialization and Loss of Nonfunctional Characters,” Annual Review of Ecology and Systematics, Vol. 26, pp. 249-268.

[129]Bejder, L. and B. K. Hall, 2002, “Limbs in Whales and Limblessness in Other Vertebrates: Mechanisms of Evolutionary and Developmental Transformation and Loss,” Evolution and Development, Vol. 4, No. 6, pp. 445-458.

[130]Goodwin, B., 2009, "Beyond the Darwinian Pardigm: Understanding Biological Forms," Evolution: The First Four Billion Years (M. Ruse and J. Travis, Eds.), The Belknap Press of Harvard University Press, Cambridge, MA, pp. 299-312.

[131]Starr, C., C. A. Evers and L. Starr, 2006, Basic Concepts in Biology, Thomson Brooks/Cole, Belmont, CA.

[132]Travis, J. and D. N. Reznick, 2009, "Adaptation," Evolution: The First Four Billion Years (M. Ruse and J. Travis, Eds.), The Belknap Press of Harvard University Press, Cambridge, MA, pp. 105-131.

[133]Campbell, N. A. and J. B. Reece, 2005, Biology, Pearson Benjamin Cummings, San Francisco.

[134]Drezner, T. and Z. Drezner, 2006, "Genetic Algorithms: Mimicking Evolution and Natural Selection in Optimization Models," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press Boca Raton, FL, pp. 157-175.

[135]Ausubel, K., 2004, "Introduction," Nature's Operating Instructions: The True Biotechnologies (K. Ausubel and J. P. Harpignies, Eds.), Sierra Club Books, San Francisco. 266

[136]Richter, K. and I. Grunwald, 2010, "Bio-inspired Polyphenolic Adhesives for Medical and Technical Applications: Introduction," Biological Adhesive Systems: From Nature to Technical and Medical Application (J. v. Byern and I. Grunwald, Eds.), Springer-Verlang/Wien, Austria, pp. 201-202.

[137]Yen, J., M. J. Weissburg, M. Helms and A. K. Goel, 2012, "Biologically Inspired Design: A Tool for Interdisciplinary Education," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 331-360.

[138]Peterson, A. T., J. Soberon, R. G. Pearson, R. P. Anderson, E. Martinez-Meyer, M. Nakamura and M. B. Araujo, 2011, "Chapter 2: Concepts of Niches," Ecological Niches and Geographic Distributions, Princeton University Press, Princeton, New Jersey, pp. 7-22.

[139]Gunderson, S. L. and R. C. Schiavone, 1995, "Microstructure of an Insect Cuticle and Applications to Advanced Composites," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 163-197.

[140]Houde, A. E., 1987, “Mate Choice Based Upon Naturally Occurring Color-Pattern Variation in a Guppy Population,” Evolution, Vol. 41, No. 1, pp. 1-10.

[141]Walther, B. A., 2003, “Do Peacocks Devote Maintenance Time to Their Ornamental Plumage? Time Budgets of Male Blue Peafoul Pavo cristatus,” Ludiana, Vol. 4, No. 2, pp. 149-154.

[142]Schluter, D., T. D. Price and L. Rowe, 1991, “Conflicting Selection Pressures and Life History Trade-Offs,” Proceedings of the Royal Society B: Biological Sciences, Vol. 246, No. 1315, pp. 11-17.

[143]Andersson, M., 1994, Sexual Selection, Princeton University Press, Princeton, NJ.

[144]Helms, M., S. S. Vattam and A. K. Goel, 2009, “Biologically Inspired Design: Process and Products,” Design Studies, Vol. 30, No. 5, pp. 606-622.

[145]Lynch, M., 2007, “The Frailty of Adaptive Hypotheses for the Origins of Organismal Complexity,” PNAS: Proceedings of the National Academy of Sciences, Vol. 104, No. 1, pp. 8597-8604.

[146]Charlesworth, B. and D. Charlesworth, 2009, "Evolution of the Genome," Evolution: The First Four Billion Years (M. Ruse and J. Travis, Eds.), The Belknap Press of Harvard University Press, Cambridge, MA, pp. 152 - 176. 267

[147]Barton, N. and L. Partridge, 2000, “Limits to Natural Selection,” BioEssays, Vol. 22, pp. 1075-1084.

[148]Stoltzfus, A. and L. Y. Yampolsky, 2009, “Climbing Mount Probable: Mutation as a Cause of Nonrandomness in Evolution,” Journal of Heredity, Vol. 100, No. 5, pp. 637-647.

[149]Hodgkinson, A. and A. Eyre-Walker, 2011, “Variation in the Mutation Rate Across Mammalian Genomes,” Nature Reviews, Vol. 12, pp. 756-766.

[150]Barton, N. H., 2000, “Genetic Hitchhiking,” Philosophical Transactions of the Royal Society B, Vol. 355, pp. 1553-1562.

[151]Meiklejohn, C. D., K. L. Montooth and D. M. Rand, 2000, “Positive and Negative Selection on the Mitochondrial Genome,” TRENDS in Genetics, Vol. 23, No. 6, pp. 259-263.

[152]Knippers, J. and T. Speck, 2012, “Design and Construction Principles in Nature and Architecture,” Bioinspiration and Biomimetics, Vol. 7, No. 1, pp. 015002.

[153]Reznick, D. N. and R. E. Recklefs, 2009, “Darwin's Bridge Between Microevolution and Macroevolution,” Nature, Vol. 457, pp. 837-842.

[154]Bar-Cohen, Y., 2012, "Introduction: Nature as a Source of Inspiring Innovation," Biomimetics:Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 1-34.

[155]Hobaek, T. C., K. G. Leinan, H. P. Linaas and C. Thaulow, 2011, “Surface Nanoengineering Inspired by Evolution,” BioNanoScience, Vol. 1, No. 3, pp. 63- 77.

[156]Langella, C., 2006, "Hybrid Design. Encoding Biological Principles in Sustainable Design," Sustainable Consumption and Production: Opportunities and Challenges, Wuppertal, Germany.

[157]Payne, J. L. and S. Finnegan, 2007, “The Effect of Geographic Range on the Extinction Risk During Background and Mass Extinction,” PNAS: Proceedings of the National Academy of Sciences, Vol. 104, No. 25, pp. 10506-10511.

[158]Fusco, G. and A. Minelli, 2010, “Phenotypic Plasticity in Development and Evolution: Facts and Concepts,” Philosophical Transactions of the Royal Society B, Vol. 365, pp. 547-556. 268

[159]Agrawal, A. A.,2001, Phenotypic Plasticity in the Interaction and Evolution of Species. Science. 294: 321-326.

[160]Boratynski, Z., E. Koskela, T. Mappes and T. A. Oksanen, 2010, “Sex-Specific Selection on Energy Metabolism - Selection Coefficients for Winter Survival,” Journal of Evolutionary Biology, Vol. 23, pp. 1969-1978.

[161]Sengupta, B., M. Stemmler, S. B. Laughlin and J. E. Niven, 2010, “Action Potential Energy Efficiency Varies Among Neuron Types in Vertebrates and Invertebrates,” PLoS Computational Biology, No. 7, pp. e1000840.

[162]Niven, J. E. and S. B. Laughlin, 2008, “Energy Limitation as a Selective Pressure on the Evolution of Sensory Systems,” The Journal of Experimental Biology, Vol. 211, pp. 1792-1804.

[163]Ruxton, G. D. and D. M. Wilkinson, 2011, “The Energetics of Low Browsing in Sauropods,” Biology Letters, Vol. 7, pp. 779-781.

[164]Barber, J., 2009, “Photosynthetic Energy Conversion: Natural and Artificial,” Chemical Society Reviews, Vol. 38, pp. 185-196.

[165]Gee, H., R. Howlett and P. Campbell, 2009, “15 Evolutionary Gems,” Nature, pp. doi:10.1038/nature07740.

[166]Ayala, F. J., 2009, "Molecular Evolution," Evolution: The First Four Billion Years (M. Ruse and J. Travis, Eds.), The Belknoap Press of Harvard University Press, Cambridge, MA, pp. 132 -151.

[167]Green, M. S., 2006, Engaging Philosophy: A Brief Introduction, Hackett Publishing Company, Indianapolis.

[168]Salmon, M. H., 2007, Introduction to Logic and Critical Thinking, Cengage Learning, Belmont, CA.

[169]World Commission on the Ethics of Scientific Knowledge and Technology,2010, The Ethical Implications of Global Climate Change. Paris, France, United Nations Educational, Scientific and Cultural Organization (UNESCO): 7-39.

[170]United Nations, 1998, Kyoto Protocol to the United Nations Framework Convention on Climate Change.

269 [171]Haas, G., F. Wetterich and U. Kopke, 2001, “Comparing Intensive, Extensified and Organic Grassland farming in Southern Germany by Process Life Cycle Assessment,” Agriculture, Ecosystems & Environment, Vol. 83, No. 1-2, pp. 43- 53.

[172]Aubin, J., E. Papatryphon, H. M. G. v. d. Werf and S. Chatzifotis, 2009, “Assessment of the Environmental Impact of Carnivorous Finfish Production Systems Using Life Cycle Assessment,” Journal of Cleaner Production, Vol. 17, No. 3, pp. 354-361.

[173]Rotz, C. A., F. Montes and D. S. Chianese, 2010, “The Carbon Footprint of Dairy Production Systems Through Partial Life Cycle Assessment,” Journal of Dairy Science, Vol. 93, No. 3, pp. 1266-1286.

[174]Peters, G. M., H. V. Rowley, S. Wiedemann, R. Tucker, M. D. Short and M. Schulz, 2010, “Red Meat Production in Australia: Life Cycle Assessment and Comparison with Overseas Studies,” Environmental Science & Technology, Vol. 44, No. 4, pp. 1327-1332.

[175]Kim, S., B. E. Dale and R. Jenkins, 2009, “Life Cycle Assessment of Corn Grain and Corn Stover in the United States,” International Journal of Life Cycle Assessment, Vol. 14, No. 2, pp. 160-174.

[176]Pimentel, D. and T. W. Patzek, 2005, “Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower,” Natural Resources Research, Vol. 14, No. 1, pp. 65-76.

[177]Lardon, L., A. Helias, B. Sialve, J.-P. Seyer and O. Bernard, 2009, “Life-Cycle Assessment of Biodiesel Production from Microalgae,” Environmental Science & Technology, Vol. 43, No. 17, pp. 6475-6481.

[178]Mooney, H. A. and R. J. Hobbs, 2000, "Introduction," Invasive Species in a Changing World (H. A. Mooney and R. J. Hobbs, Eds.), Island Press, Washington, DC.

[179]Lee, C. E., 2002, “Evolutionary Genetics of Invasive Species,” Trends in Ecology & Evolution, Vol. 17, No. 8, pp. 386-391.

[180]Crooks, J. A., 2002, “Characterizing Ecosystem-Level Consequences of Biological Invasions: The Role of Ecosystem Engineers,” Oikos, Vol. 97, pp. 153-166.

270 [181]Pimentel, D., R. Zuniga and D. Morrison, 2005, “Update on the Environmental and Economic Costs Associated with Alien-Invasive Species in the United States,” Ecological Economics, Vol. 52, No. 3, pp. 273-288.

[182]National Resource Management Ministerial Council - Vertebrate Pests Committee, 2010, National Feral Camel Action Plan: A National Strategy for the Management of Feral Camels in Australia. Barton, Australian Capital Territory, Commonwealth of Australia, http://www.environment.gov.au/biodiversity/ invasive/publications/pubs/feral-camel-action-plan.pdf

[183]Clark, P.,2011, Australia Poised to Allow Camel Cull. The Financial Times. London.

[184]Coleman, F. C. and S. L. Williams, 2002, “Overexploiting Marine Ecosystem Engineers: Potential Consequences for Biodiversity,” Trends in Ecology & Evolution, Vol. 17, No. 1, pp. 40-44.

[185]Jones, C. G., J. H. Lawton and M. Shachak, 1997, “Positive and Negative Effects of Organisms as Physical Ecosystem Engineers,” Ecology, Vol. 78, No. 7, pp. 1946- 1957.

[186]Wilkinson, D. M., E. G. Nisbet and G. D. Ruxton, 2012, “Could Methane Produced by Sauropod Dinosaurs Have Helped Drive Mesozoic Climate Warmth?,” Current Biology, Vol. 22, No. 9, pp. R292-R293.

[187]Benyus, J., 2004, "Biomimicry: What Would Nature Do Here?," Nature's Operating Instructions: The True Biotechnologies (K. Ausubel and J. P. Harpignies, Eds.), Sierra Club Books, San Francisco.

[188]Turney, T., 2009, "Future Materials and Performance," Technology, Design and Process Innovation in the Built Environment (P. Newton, K. Hampson and R. Drogemuller, Eds.), Taylor & Francis, New York, pp. 31-53.

[189]Bar-Cohen, Y., 2006, "Biomimetics: Reality, Challenges, and Outlook," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 495-513.

[190]Bar-Cohen, Y., 2012, "Biomimetics - Reality, Challenges, and Outlook," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 693-714.

[191]Golley, F. B., 1960, “Energy Dynamics of a Food Chain of an Old-Field Community,” Ecological Monographs, Vol. 30, No. 2, pp. 187-206. 271

[192]Yakimov, M. M., K. N. Timmis and P. N. Golyshin, 2007, “Obligate Oil-Degrading Marine Bacteria,” Current Opinion in Biotechnology, Vol. 18, pp. 257-266.

[193]Pavlik, B. M. and E. Manning, 1993, “Assessing Limitations on the Growth of Endangered Plant Populations, II. Seed Production and Seed Bank Dynamics of Erysimum capitatum ssp. Angustatum and Oenothera deltoides ssp. Howellii,” Biological Conservation, Vol. 65, No. 3, pp. 267-278.

[194]Wolpert, H. D., 2012, "Biological Optics," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 267-305.

[195]Kalaitzis, J. A., R. Chau, G. S. Kohli, S. A. Murray and B. A. Neilman, 2012, “Biosynthesis of Toxic Naturally-Occuring Seafood Contaminants,” Toxicon, Vol. 56, No. 2, pp. 244-258.

[196]Ferrao-Filho, A. S., S. M. F. O. Azevedo and W. R. DeMott, 2000, “Effects of Toxic and Non-Toxic Cyanobacteria on the Life History of Tropical and Temperate Cladocerans,” Freshwater Biology, Vol. 45, pp. 1-19.

[197]Mendoza, E. and R. Dirzo, 2009, “Seed Tolerance to Predation: Evidence from the Toxic Seeds of the Buckeye Tree (Aesculus californica; Sapindaceae),” American Journal of Botany, Vol. 96, No. 7, pp. 1255-1261.

[198]Akhtar, Y., M. B. Isman, L. A. Niehaus, C.-H. Lee and H.-S. Lee, 2012, “Antifeedant and Toxic Effects of Naturally Occuring and Synthetic Quinones to the Cabbage Looper, Trichoplusia ni,” Crop Protection, Vol. 31, No. 1, pp. 8-14.

[199]Gibbs, H. L. and S. P. Mackessy, 2009, “Functional Basis of a Molecular Adaptation: Prey-Specific Toxic Effects of Venom from Sistrurus Rattlesnakes,” Toxicon, Vol. 53, No. 6, pp. 672-679.

[200]Price, D. R. G., H. A. Bell, G. Hinchliffe, E. Fitches, R. Weaver and J. A. Gatehouse, 2009, “A Venom Metalloproteinase from the Parasitic Wasp Eulophus pennicornis is toxic towards its host, tomato moth (Lacanobia oleracae),” Insect Molecular Biology, Vol. 18, No. 2, pp. 195-202.

[201]Wainwright, S. A., 1995, "What We Can Learn from Soft Biomaterials and Structures," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 1-12.

272 [202]Strange, D. G. T. and M. L. Oyen, 2012, "Biomimetic Composites," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 169-212.

[203]Biello, D.,2008, Cement from CO2: A Concrete Cure for Global Warming? Scientific American, http://www.scientificamerican.com/article.cfm?id=cement- from-carbon-dioxide.

[204]Feng, S. and R. Xu, 2001, “New Materials in Hydrothermal Synthesis,” Accounts of Chemical Research, Vol. 34, No. 3, pp. 239-247.

[205]Kato, C. and Y. Nogi, 2001, “Correlation Between Phylogenetic Structure and Function: Examples from Deep-Sea Shewanella,” FEMS Microbiology Ecology, Vol. 35, pp. 223-230.

[206]Abe, F. and K. Horikoshi, 2001, “The Biotechnological Potential of Piezophiles,” TRENDS in Biotechnology Vol. 19, No. 3, pp. 102-108.

[207]Yayanos, A. A., R. V. Boxtel and A. S. Dietz, 1983, “Reproduction of Bacillus stearothermophilus as a Function of Temperature and Pressure,” Applied and Environmental Microbiology, Vol. 46, No. 6, pp. 1357-1363.

[208]Wainwright, S. A., W. D. Biggs, J. D. Currey and J. M. Gosline, 1976, Mechanical Design in Organisms, John Wiley & Sons, Inc., New York.

[209]Paturi, F. R., 1976, "Chapter 16: Where Do We Go from Here?," Nature: Mother of Invention: The Engineering of Plant Life, Harper & Row, New York, NY, pp. 199-203.

[210]Crutzen, P. J., I. Aselmann and W. Seiler, 1986, “Methane Production by Domestic Animals, Wild Ruminants, Other Herbivorous Fauna, and Humans,” Tellus, Vol. 38B, pp. 271-284.

[211]Parveen, S., K. M. Portier, K. Robinson, L. Edmiston and M. L. Tamplin, 1999, “Discriminant Analysis of Ribotype Profiles of Escherichia coli for Differentiating Human and Nonhuman Sources of Fecal Pollution,” Applied and Environmental Microbiology, Vol. 65, No. 7, pp. 3142-3147.

[212]Geldreich, E. E. and B. A. Kenner, 1969, “Concepts of Fecal Streptococci in Stream Pollution,” Water Pollution Control Federation, Vol. 41, No. 8, pp. R336-R352.

[213]Liu, C., 2007, “Micromachined Biomimetic Artificial Haircell Sensors,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S162-S169. 273

[214]Fotheringham, N., 1976, “Population Consequences of Shell Utilization by Hermit Crabs,” Ecology, Vol. 57, No. 3, pp. 570-578.

[215]Department of Energy, 2013, How Fossil Fuels Were Formed. Washington, D.C. 2013, http://www.fossil.energy.gov/education/energylessons/coal/gen_howformed.html.

[216]Bond, W. J. and J. E. Keeley, 2005, “Fire as a Global 'Herbivore': The Ecology and Evolution of Flammable Ecosystems,” Trends in Ecology & Evolution, Vol. 20, No. 7, pp. 387-394.

[217]Ennos, A. R., 2005, "Compliance in Plants," Compliant Stuctures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA, pp. 21-37.

[218]Hughes, T. P., A. H. Baird, D. R. Bellwood, M. Card, S. R. Connolly, C. Folke, R. Grosberg, O. Hoegh-Guldberg, J. B. C. Jackson, J. Kleypas, J. M. Lough, P. Marshall, M. Nystrom, S. R. Palumbi, J. M. Pandolfi, B. Rosen and J. Roughgarden, 2003, “Climate Change, Human Impacts, and the Resilience of Coral Reefs,” Science, Vol. 301, pp. 929-933.

[219]Dennis, R. G. and H. Herr, 2006, "Engineered Muscle Actuators: Cells and Tissues," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 243-266.

[220]Otero, T., 2008, “Reactive Conducting Polymers as Actuating Sensors and Tactile Muscle,” Bioinspiration and Biomimetics, Vol. 3, No. 3, pp. 035004.

[221]Tester, J. W., E. M. Drake, M. J. Driscoll, M. W. Golay and W. A. Peters, 2005, Sustainable Energy: Choosing Among Options, MIT Press, Cambridge, MA.

[222]French, M., 1994, Invention and Evolution: Design in Nature and Engineering, Cambridge University Press, New York.

[223]Smil, V., 1999, Energies: An Illustrated Guide to the Biosphere and Civilization, MIT Press, Cambridge, MA.

[224]Weber, P. W., M. M. Murray, L. E. Howle and F. E. Fish, 2009, “Comparison of Real and Idealized Cetacean Flippers,” Bioinspiration and Biomimetics, Vol. 4, No. 4, pp. 046001.

274 [225]Vargas, A., R. Mittal and H. Dong, 2008, “A Computational Study of the Aerodynamic Performance of a Dragonfly Wing Section Gliding in Flight,” 2008, Vol. 3, No. 2, pp. 026004.

[226]Bhushan, B., 2012, Biomimetics: Bioinspired Hierarchial-Structured Surfaces for Green Science and Technology, Springer, New York.

[227]Vincent, J., 2009, “Biomimetics - A Review,” Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering and Medicine, Vol. 223, No. 8, pp. 919-939.

[228]Anastas, P. T. and J. C. Warner, 1998, "Future Trends in Green Chemistry," Green Chemistry: Theory and Practice, Oxford University Press, Oxford, pp. 115-119.

[229]Stachelberger, H., P. Gruber and I. C. Gebeshuber, 2011, "Biomimetics: Its Technological and Societal Potential," Biomimetics - Materials, Structures and Processes (P. Gruber, D. Bruckner, C. Hellmichet al, Eds.), Springer, New York.

[230]Gruber, P., 2011, "Biomimetics in Architecture [Architekturbionik]," Biomimetics - Materials, Structures and Processes (P. Gruber, D. Bruckner, C. Hellmichet al, Eds.), Springer, New York, NY, pp. 127-148.

[231]Vogel, S., 2009, “Nosehouse: Heat-Conserving Ventilators Based on Nasal Counterflow Exchangers,” Bioinspiration and Biomimetics, Vol. 4, No. 4, pp. 046004.

[232]Velcro,2011, Who is Velcro USA Inc.? 2012, http://www.velcro.com/index.php?page=company.

[233]Vattam, S., B. Wiltgen, M. Helms, A. K. Goel and J. Yen, 2011, "DANE: Fostering Creativity in and through Biologically Inspired Design," Design Creativity 2010 (T. Taura and Y. Nagai, Eds.), Springer-Verlag London Limited, pp. 115-122.

[234]Nagel, J. K. S., R. B. Stone and D. A. McAdams, 2010, "An Engineering-to- Biology Thesaurus for Engineering Design," ASME IDETC/CIE 2010, Montreal, Canada, DETC2010-28233.

[235]Turner, C. H., 2006, “Bone Strength: Current Concepts,” Annals of the New York Academy of Sciences, Vol. 1068, No. 1, pp. 429-446.

[236]Weinkamer, R. and P. Fratzl, 2011, “Mechanical Adaptation of Biological Materials - The Examples of Bone and Wood,” Materials Science and Engineering C, Vol. 31, pp. 1164-1173. 275

[237]Muller, R. and R. Kuc, 2007, “Biosonar-Inspired Technology: Goals, Challenges and Insights,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S146-S161.

[238]Sullivan, T. and F. Regan, 2011, “The Characterization, Replication and Testing of Dermal Denticles of Scyliorhinus canicula for Physical Mechanisms of Biofouling Prevention,” Bioinspiration and Biomimetics, Vol. 6, No. 4, pp. 1-11.

[239]Masselter, T., G. Bauer, F. Gallenmuller, T. Haushahn, S. Poppinga, C. Schmitt, R. Seidel, O. Speck, M. Thielen, T. Speck, W. Barthlott, P. Ditsche-Kuru, H. Immink, J. Bertling, N. Molders, A. Nellesen, M. Rechberger, F. Cichy, M. Gude, M. Hermann, K. Lunz, J. Knippers, J. Lienhard, S. Schleicher, R. Luchsinger, C. Mattheck, I. Tesari, M. Milwich, T. Stegmaier, C. Neinhuis and H. Schwager, 2012, "Biomimetic Products," Biomimetics: Nature-Based Innovation (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 377-429.

[240]Lipson, H., 2006, "Evolutionary Robotics and Open-Ended Design Automation," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 129-153.

[241]Nelson, R. A., J. G. Edgar Folk, E. W. Pfeiffer, J. J. Craighead, C. J. Jonkel and D. L. Steiger, 1983, "Behavior, Biochemistry, and Hibernation in Black, Grizzly, and Polar Bears," Fifth International Conference on Bear Research and Management, Madison, Wisconsin.

[242]Lowe, S., M. Browne, S. Boudjelas and M. D. Poorter,2000, 100 of the World's Worst Invasive Alien Species: A Selection from the Global Invasive Species Database. Auckland, New Zealand, The Invasive Species Specialist Group (ISSG). 2013, http://calendar.k-state.edu/withlab/consbiol/IUCN_invaders.pdf.

[243]Reap, J., F. Roman, S. Duncan and B. Bras, 2008, “A Survey of Unresolved Problems in Life Cycle Assessment: Part 2: Impact Assessment and Interpretation,” International Journal of Life Cycle Assessment, Vol. 13, pp. 374- 388.

[244]Telenko, C., 2012, "Probabilistic Graphical Modeling as a Use Stage Inventory Method for Environmentally Concious Design," Mechanical Engineering, Texas, Austin.

[245]Vattam, S. S. and A. K. Goel, 2011, "Foraging for Inspiration: Understanding and Supporting the Online Information Seeking Practices of Biologically Inspired Designers," ASME 2011 International Design Engineering Technical Conferences

276 & Computeres and Information in Engineering Conference, Washington, DC, DETC2011-48238.

[246]Yen, J. and M. Weissburg, 2007, “Editorial: Perspectives on Biologically Inspired Design: Introduction to the Collected Contributions,” Bioinspiration and Biomimetics, Vol. 2, No. 4.

[247]Shu, L. H., 2010, “A Natural-Language Approach to Biomimetic Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, No. 4, pp. 507-519.

[248]Beck, B. B., 1980, Animal Tool Behavior: The Use and Manufacture of Tools by Animals, Garland Publishing, Inc. , New York.

[249]Hunter, J. P., 1998, “Key Innovations and the Ecology of Macroevolution,” Trends in Ecology & Evolution, Vol. 13, No. 1, pp. 31-36.

[250]Zikmund, W. G., 2003, Business Research Methods, Thomson Southwestern, Mason, Ohio.

[251]Ask Nature, 2013, Browse Biomimicry, The Biomimicry 3.8 Institute. 2013, http://www.asknature.org/browse.

[252]2011, Bioinspiration and Biomimetics, Vol. 6, No. 1, pp. 014001-019501, http://iopscience.iop.org/1748-3190/6/1.

[253]2010, “Special Issue on Bioinspired Flight,” Bioinspiration and Biomimetics, Vol. 5, No. 4, pp. 040401-049901.

[254]Bird, W.,2008, Natural by Design. The Japan Times Online, http://search.japantimes.co.jp/cgi-bin/fl20080824x1.html.

[255]Bionics, Wikipedia. 2011, http://en.wikipedia.org/wiki/Bionics.

[256]Pailhas, Y., C. Capus, K. Brown and P. Moore, 2010, “Analysis and Classification of Broadband Echoes Using Bio-Inspired Dolphin Pulses,” Journal of the Acoustical Society of America, Vol. 127, No. 6, pp. 3809-3820.

[257]Youngblood, J. P. and N. R. Sottos, 2008, “Bioinspired Materials for Self-Cleaning and Self-Healing,” MRS Bulletin, Vol. 33, pp. 732-738.

277 [258]Development of Oil Resistant Material That Prevents Fingerprint Smutching, Say People. 2013, http://saypeople.com/2011/12/05/development-of-oil-resistant- material-that-prevents-fingerprint-smutching/#axzz2ReHWxT3H.

[259]HitchScan Wireless Trailer System - Wireless Sensor, RVFun Products. 2013, http://www.rvfunproducts.com/hitchscan-wireless-trailer-system-wireless-sensor- p-2291.html.

[260]Joanne,Top 10 Cutest Animals Threatened by BP Oil Spill, Ranker. 2013, http://www.ranker.com/list/top-10-cutest-animals-threatened-by-bp-oil- spill/joanne.

[261]Palter, S. F.,2006, Geckos Grabbing Gizmos in the Or, docinthemachine.com. 2013, http://docinthemachine.com/geckosintheor/.

[262]Karp, J.,2008, Sticky Tape to Heal Surgical Incisions, MIT Technology Review, http://www.technologyreview.com/news/409625/sticky-tape-to-heal-surgical- incisions/.

[263]Ushnaroy,2010, The Exciting Glass Bottom Boat Ride on Blue Bay Marine Park, Mauritius. 2013, http://www.travelihub.com/the-exciting-glass-bottom-boat-ride- on-blue-bay-marine-park-mauritius/.

[264]Sharklet Technologies Inc., 2010, Technology: Inspired by Nature. 2012, http://www.sharklet.com/technology/.

[265]Brennan, A. B., R. H. Baney, M. L. Carman, T. G. Estes, A. W. Feinberg, L. H. Wilson and J. F. Schumacher,2010, Surface Topographies for Non-Toxic Bioadhesion Control. United States. US 7,650,848 B2.

[266]Brennan, A. B., C. J. Long, J. W. Bagan, J. F. Schumacher and M. M. Spiecker,2010, Surface Topographies for Non-Toxic Bioadhesion Control. United States. US 2010/0226943 A1.

[267]Chung, K. K., J. F. Schumacher, E. M. Sampson, R. A. Burne, P. J. Antonelli and A. B. Brennan, 2007, “Impact of Engineered Surface Microtopography on Biofilm Formation of Staphylococcus Aureus,” Biointerphases, Vol. 2, No. 2, pp. 89-94.

[268]IEA,2010, Energy Balances of Non-OECD Countries 2010. Paris, France, International Energy Agency: II.303-II.304.

278 [269]2010, Test Your Knowledge of Biomimicry, CNN Tech. 2011, http://www.cnn.com/2010/TECH/innovation/06/21/biomimicry.design.quiz/index .html.

[270]Allen, R., 2010, "Introduction," Bulletproof Feathers: How Science Uses Nature's Secrets to Design Cutting-Edge Technology (R. Allen, Ed.), The University of Chicago Press, Chicago, pp. 6-21.

[271]Wikipedia,2010, Bionics. 2010, http://en.wikipedia.org/wiki/Bionics.

[272]Kohli, N.,2007, Biofouling and Design of a Biomimetic Hull-Grooming Tool. West Bethesda, Maryland, Naval Surface Warefare Center: Carderock Division: 1-38.

[273]Vattam, S., M. Helms and A. K. Goel,2007, Biologically-Inspired Innovation in Engineering Design: A Cognitive Study, Graphics, Visualization and Usability Center, Georgia Institute of Technology.

[274]Zari, M. P., 2010, “Biomimetic Design for Climate Change Adaptation and Mitigation,” Architectural Science Review, Vol. 53, No. 2, pp. 172-183.

[275]Biomimicry Institute, 2010, Biolytix Water Filter, Ask Nature. 2010, http://www.asknature.org/product/f9d2ab73e15de8d6e44bc15cac4549a3.

[276]Biomimicry Institute, 2010, CAO and SKO Design Software, Ask Nature. 2010, http://www.asknature.org/product/99d6740a0a07a9d003480f1c414ee177.

[277]Venton, D.,2011, Mother Nature as Engineer: 9 Design Tricks Borrowed from Biology. Wired Science, http://www.wired.com/wiredscience/2011/08/ biomimicry-gallery/?pid=1785.

[278]Biomimicry Institute, 2010, i2 Modular Carpet, Ask Nature. 2010, http://www.asknature.org/product/a84a9167f21f1cc690e0e673c4808833.

[279]FLOR, I.,2012, About Our Products. 2012, http://www.interfaceflor.com/Default.aspx?Section=2&Sub=3.

[280]Biomimicry Institute, 2010, Sharklet AF, Ask Nature. 2010, http://www.asknature.org/product/3c21a56f0ba2ae549894a2bf79372bda.

[281]Sharklet Technologies, Inc., 2010, Home. 2011, http://www.sharklet.com/.

[282]Biomimicry Institute,2010, Shinkansen Train, Ask Nature. 2010, http://www.asknature.org/product/6273d963ef015b98f641fc2b67992a5e. 279

[283]Biomimicry Institute, 2009, Sir Marc Isambard Brunel’s Tunnel Borer, Ask Nature. 2010, http://www.asknature.org/product/689fd8eaadf3fb570097fa5c4ffb7049.

[284]Biomimicry Institute, 2009, Baleen Filters Water Filters, Ask Nature. 2010, http://www.asknature.org/product/0fdee3b68d08f075009711803dc93c16.

[285]Calera,Our Story. 2012, http://calera.com/index.php/about_us/our_story/.

[286]Biomimicry Institute, 2010, Calera MAP Cement-Making Process, Ask Nature. 2010, http://www.asknature.org/product/9242c6b587aba1877c788cd8409d60ac.

[287]Biomimicry Institute, 2009, HotZone Radiant Heater, Using IRLens, Ask Nature. 2010, http://www.asknature.org/product/0571c3e5e3376604c4c51840dbc3281d.

[288]Airbus,2012, Biomimicry, Imitating Nature's Best Ideas. 2012, http://www.airbus.com/innovation/eco-efficiency/design/biomimicry/?contentId= [_TABLE%3Att_content%3B_FIELD%3Auid]%2C&cHash=22935adfac92fcbbd 4ba4e1441d13383.

[289]Biomimicry Institute, 2010, Mirasol Display Technology, Ask Nature. 2010, http://www.asknature.org/product/af429a05af212ee9fc74977247408bf5.

[290]Vella, M.,Design Tips from Mother Nature. Bloomberg Businessweek. 2012, http://images.businessweek.com/ss/08/02/0209_green_biomimic/source/1.htm.

[291]Biomimicry Institute, 2010, Crystal Palace in London, Ask Nature. 2010, http://www.asknature.org/product/a13b2a14313fcc7123e827269a1d8a73.

[292]Cameron, D. O.,2005, Biolytic Filtration. USPTO. United States, Dowmus Pty. Ltd. US 6,890,439 B2.

[293]Cameron, D. O.,1997, Method for Treating Wastewater and Solid Organic Waste. USPTO. United States, Dowmus Pty Ltd. 5,633,163.

[294]Vincent, J., 2010, "Chapter 6: New Materials and Natural Design," Bulletproof Feathers: How Science Uses Nature's Secrets to Design Cutting-Edge Technology (R. Allen, Ed.), The University of Chicago Press, Chicago, pp. 132-171.

[295]Cameron, D. O.,1999, Effluent Treatment System. USPTO. United States, Downus Pty. Ltd. 5,919,366.

280 [296]Cameron, D. O.,1999, Self-Cleansing Filter. USPTO. United States, Dowmus Pty Ltd. 5,976,374.

[297]Biolytix Water, 2011, Why Biolytix? 2011, http://www.biolytix.co.nz/commercial/ why_biolytix_25_key_benefits/.

[298]Yen, J., 2010, "Chapter 1: Marine Dynamics," Bulletproof Feathers: How Science Uses Nature's Secrets to Design Cutting-Edge Technology (R. Allen, Ed.), The University of Chicago Press, Chicago, pp. 22-43.

[299]Okada, M., Y. Nakamura and S. Ban, 2001, "Design of Programmable Passive Compliance Shoulder Mechanism," Proceedings of the 2001 IEEE International Conference on Robotics & Automation, Seoul, Korea.

[300]Wright, I. C., R. R. Neptune, A. J. v. d. Bogert and B. M. Nigg, 1998, “Passive Regulation of Impact Forces in Heel-Toe Running,” Clinical Biomechanics, Vol. 13, pp. 521-531.

[301]Honig, C. R., C. L. Odoroff and J. L. Frierson, 1982, “Active and Passive Capillary Control in Red Muscle at Rest and in Excercise,” American Journal of Physiology - Heart and Circulatory Physiology, Vol. 243, pp. H196-H206.

[302]Dietschy, J. M., 1968, “Mechanisms for the Intestinal Absorption of Bile Acids,” Journal of Lipid Research, Vol. 9, pp. 297-309.

[303]Dechev, N., W. L. Cleghorn and S. Naumann, 2001, “Multiple Finger, Passive Adaptive Grasp Prosthetic Hand,” Mechanism and Machine Theory, Vol. 36, pp. 1157-1173.

[304]Sirovich, L. and S. Karlsson, 1997, “Turbulent Drag Reduction by Passive Mechanisms,” Nature, Vol. 388.

[305]Lin, C.-C., J.-M. Ueng and T.-C. Huang, 1999, “Seismic Response Reduction of Irregular Buildings Using Passive Tuned Mass Dampers,” Engineering Structures, Vol. 22, pp. 513-524.

[306]Jolly, M. R., D. J. Rossetti, M. A. Norris and L. R. Miller,1998, Hybrid Active- Passive Noise and Vibration Control System for Aircraft. USPTO. United States, Lord Corporation. 5,845,236.

[307]Peippo, K., P. Kauranen and P. D. Lund, 1991, “A Multicomponent PCM Wall Optimized for Passive Solar Heating,” Energy and Buildings, Vol. 17, pp. 259- 270. 281

[308]Letan, R., V. Dubovsky and G. Ziskind, 2003, “Passive Ventilation and Heating by Natural Convection in a Multi-Storey Building,” Building and Environment, Vol. 38, pp. 197-208.

[309]Canbazoglu, S., A. Sahinaslan, A. Ekmekyapar, Y. G. Aksoy and F. Akarsu, 2005, “Enhancement of Solar Thermal Energy Storage Performance Using Sodium Thiosulfate Pentahydrate of a Conventional Solar Water-Heating System,” Energy and Buildings, Vol. 37, pp. 235-242.

[310]Grise, W. and C. Patrick, 2002, “Passive Solar Lighting Using Fiber Optics,” Journal of Industrial Technology, Vol. 19, No. 1, pp. 2-7.

[311]Collins, S., A. Ruina, R. Tedrake and M. Wisse, 2005, “Efficient Bipedal Robots Based on Passive-Dynamic Walkers,” Science, Vol. 307, No. 5712, pp. 1082- 1085.

[312]Kljuno, E., J. J. Zhu, R. L. W. II and S. M. Reilly, 2011, "A Biomimetic Elastic Cable Driven Quadruped Robot - The Robocat," International Mechanical Engineering Congress & Exposition, Denver, Colorado, IMECE2011-63534.

[313]Lentink, D. and A. A. Biewener, 2010, “Nature-Inspired Flight - Beyond the Leap,” Bioinspiration and Biomimetics, Vol. 5, No. 4, pp. 1-9.

[314]Dem Bones Dem Bones, Simply Healthy. 2012, http://simplyhealthy4u.blogspot.com/.

[315]Dickinson, M. H. and M. S. Tu, 1997, “The Function of Dipteran Flight Muscle,” Comparative Biochemistry and Physiology, Vol. 116A, No. 3, pp. 223-238.

[316]Whittington, B., A. Silder, B. Heiderscheit and D. G. Thelen, 2008, “The Contribution of Passive-Elastic Mechanisms to Lower Extremity Joing Kinetics During Human Walking,” Gait & Posture, Vol. 27, No. 4, pp. 628-634.

[317]Gottig, N., E. V. Elias, R. Quiroga, M. J. Nores, A. J. Solari, M. C. Touz and H. D. Lujan, 2006, “Active and Passive Mechanisms Drive Secretory Granule Biogenesis During Differentiation of the Intestinal Parasite Giardia lamblia,” Journal of Biological Chemistry, Vol. 281, No. 26, pp. 18156-18166.

[318]Doherty, T. M., K. Asotra, L. A. Fitzpatrick, J.-H. Qiao, D. J. Wilkin, R. C. Detrano, C. R. Dunstan, P. K. Shah and T. B. Rajavashisth, 2003, “Calcification in Atherosclerosis: Bone Biology and Chronic Inflammation at the Arterial

282 Crossroads,” Proceedings of the National Academy of Sciences of the United States of America, Vol. 100, No. 20, pp. 11201-11206.

[319]Saunders, F., B. A. Trimmer and J. Rife, 2011, “Modeling Locomotion of a Soft- Bodied Arthropod Using Inverse Dynamics,” Bioinspiration and Biomimetics, Vol. 6, pp. 016001.

[320]Pamecha, A., C.-J. Chiang, D. Stein and G. Chirikjian, 1996, "Design and Implementation of Metamorphic Robots," The 1996 ASME Design Engineering Technical Conference and Computers in Engineering Conference, Irvine, California, 96-DETC/MECH-1149.

[321]Seepersad, C. C., B. M. Dempsey, J. K. Allen, F. Mistree and D. L. McDowell, 2004, “Design of Multifunctional Honeycomb Materials,” American Institute of Aeronautics and Astronautics Journal, Vol. 42, No. 5, pp. 1025-1033.

[322]Ulrich, K. T. and S. D. Eppinger, 2004, Product Design and Development, 3rd Edition, McGraw-Hill/Irwin, New York.

[323]Cutherell, D., 1996, "Chapter 16: Product Architecture," The PDMA Handbook of New Product Development (J. Milton D. Rosenau, A. Griffin, G. A. Castellion and N. F.Anschuetz, Eds.), John Wiley & Sons, New York, pp. 217-235.

[324]Stone, R. B., K. L. Wood and R. H. Crawford, 2000, “A Heuristic Method for Identifying Modules for Product Architectures,” Design Studies, Vol. 21, No. 1, pp. 5-31.

[325]Otto, K. and K. Wood, 2001, Product Design: Techniques in Reverse Engineering and New Product Development, Prentice Hall, Upper Saddle Ridge, New Jersey.

[326]Sosa, M. E., S. D. Eppinger and C. M. Rowles, 2003, “Identifying Modular and Integrative Systems and Their Impact on Design Team Interactions,” Journal of Mechanical Design, Vol. 125, pp. 240-252.

[327]Newcomb, P. J., B. Bras and D. W. Rosen, 1996, "Implications of Modularity on Product Design for the Life Cycle," The 1996 ASME Design Engineering Technical Conferences and Computers in Engineering Conference, Irvine, California, 96-DETC/DTM-1516.

[328]Liu, K. and L. Jiang, 2011, “Bio-Inspired Design of Multiscale Structures for Function Integration,” Nano Today, Vol. 6, pp. 155-175.

283 [329]Stahlberg, R. and M. Taya, 2006, "Nastic Structures: The Enacting and Mimicking of Plant Movements," Biomimetics: Biologically Inspired Technologies (Y. Bar- Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 473-493.

[330]Pandremenos, J., E. Vasiliadis and G. Chryssolouris, 2012, “Design Architectures in Biology,” Procedia CIRP, Vol. 3, pp. 448-452.

[331]Jose, A. and M. Tollenaere, 2005, “Modular and Platform Methods for Product Family Design: Literature Analysis,” Journal of Intelligent Manufacturing, Vol. 16, pp. 371-390.

[332]Tseng, H.-E., C.-C. Chang and J.-D. Li, 2008, “Modular Design to Support Green Life-Cycle Engineering,” Expert Systems with Applications, Vol. 34, pp. 2524- 2537.

[333]Umeda, Y., S. Fukushige, K. Tonoike and S. Kondoh, 2008, “Product Modularity for Life Cycle Design,” CIRP Annals - Manufacturing Technology, Vol. 57, pp. 13-16.

[334]Gu, P., M. Hashemian and S. Sosale, 1997, “An Integrated Modular Design Methodology for Life-Cycle Engineering,” Annals of the CIRP, Vol. 46, No. 1, pp. 71-74.

[335]Gu, P. and S. Sosale, 1999, “Product Modularization for Life Cycle Engineering,” Robotics and Computer Integrated Manufacturing, Vol. 15, pp. 387-401.

[336]Lucotti, A. and G. Zerbi, 2007, “Fiber-Optic SERS Sensor with Optimized Geometry,” Sensors and Actuators B, Vol. 121, pp. 356-364.

[337]Anthony, D. K., S. J. Elliott and A. J. Keane, 2000, “Robustness of Optimal Design Solutions to Reduce Vibration Transmission in a Lightweight 2-D Structure, Part I: Geometric Design,” Journal of Sound and Vibration, Vol. 229, No. 3, pp. 505- 528.

[338]Commenge, J. M., L. Falk, J. P. Corriou and M. Matlosz, 2002, “Optimal Design Flow Uniformity in Microchannel Reactors,” AIChE Journal, Vol. 48, No. 2, pp. 345-358.

[339]Benini, E., 2004, “Three-Dimensional Multi-Objective Design Optimization of a Transonic Compressor Rotor,” Journal of Propulsion and Power, Vol. 20, No. 3, pp. 559-565.

284 [340]Kohlmann, K. T., M. Thiemann and W. H. Brunger, 1991, “E-Beam Induced X-Ray Mask Repair with Optimized Gas Nozzle Geometry,” Microelectronic Engineering, Vol. 13, pp. 279-282.

[341]Lin, C.-Y., R. M. Schek, A. S. Mistry, X. Shi, A. G. Mikos, P. H. Krebsbach and S. J. Hollister, 2005, “Functional Bone Engineering Using ex Vivo Gene Therapy and Topology-Optimized, Biodegradable Polymer Composite Scaffolds,” Tissue Engineering, Vol. 11, pp. 1589-1598.

[342]Timmins, L. H., M. R. Moreno, C. A. Meyer, J. C. Criscione, A. Rachev and J. E. M. Jr., 2007, “Stented Artery Biomechanics and Device Design Optimization,” Medical & Biological Engineering and Computing, Vol. 45, pp. 505-513.

[343]Huh, D., Y.-s. Torisawa, G. A. Hamilton, H. J. Kim and D. E. Ingber, 2012, “Microengineered Physiological Biomimicry: Organs-on-Chips,” Lab on a Chip, Vol. 12, pp. 2156-2164.

[344]Martin-Palma, R. J. and A. Lakhtakia, 2012, “Engineered Biomimicry for Harvesting Solar Energy: A Bird's Eye View,” International Journal of Smart and Nano Materials, pp. 1-8.

[345]Winter, A. G., A. H. Slocum, A. E. Hosoi and R. L. H. Deits, 2009, "The Design and Testing of Roboclam: A Machine Used to Investigate and Optimize Razor Clam-Inspired Burrowing Mechanisms for Engineering Applications," IDETC/CIE 2009, San Diego, California, DETC2009-86808.

[346]Arzt, E., 2006, “Biological and Artificial Attachment Devices: Lessons for Materials Scientists from Flies and Geckos,” Materials Science and Engineering C, Vol. 26, pp. 1245-1250.

[347]Reichman, O. J., T. G. Whitham and G. A. Ruffner, 1982, “Adaptive Geometry of Burrow Spacing in Two Pocket Gopher Populations,” Ecology, Vol. 63, No. 3, pp. 687-695.

[348]Andersen, D. C., 1982, “Belowground Herbivory: The Adaptive Geometry of Geomyid Burrows,” The American Naturalist, Vol. 119, No. 1, pp. 18-28.

[349]Biolytix. 2012, http://www.environmentalplumbingsolutions.com.au/biolytix.htm.

[350]Naya, D. E., C. Veloso, J. L. P. Munoz and F. Bozinovic, 2007, “Some Vaguely Explored (But Not Trivial) Costs of Tail Autotomy in Lizards,” Comparative Biochemistry and Physiology, Part A, Vol. 146, No. 2, pp. 189-193.

285 [351]Gregorich, E. G., L. W. Turchenek, M. R. Carter and D. A. Angers, Eds., 2001, Soil and Environmental Science Dictionary, CRC Press, Boca Raton, FL.

[352]Phillips, M., 2002, "Wetlands," Biology (R. Robinson, Ed.), New York, Vol. 4, pp. 197-198.

[353]The American Heritage Science Dictionary, 2005, Riparian. The Free Dictionary, Farlex, Inc. 2012, http://www.thefreedictionary.com/riparian.

[354]Green, K.,2009, Maintaining Composure While Decomposing. Gardening for Nature. 2012, http://gardeningfornature.blogspot.com/2009/11/maintaining- composure-while-decomposing.html.

[355]Jo-Ann,2011, The Lay of the Land. 2012, http://bilberryhill.wordpress.com/.

[356]Taylor, M., W. P. Clarke and P. F. Greenfield, 2003, “The Treatment of Domestic Wastewater Using Small-Scale Vermicompost Filter Beds,” Ecological Engineering, Vol. 21, pp. 197-203.

[357]Biolytix,How it Works: In Pictures. 2012, http://www.biolytix.com/in-pictures/.

[358]Biolytix,Biolytix... Award Winning Wastewater Treatment Systems. 2012, http://www.biolytix.com/.

[359]Biolytix,How It Works: Biolytix Copies Nature. 2012, http://www.biolytix.com/copies-nature/.

[360]Biolytix Southren Africa, 2008, How Biolytix Works. 2012, http://www.biolytix.co.za/?page_id=4.

[361]Turner, S., 2009, “ASIT - A Problem Solving Strategy for Education and Eco- Friendly Sustainable Design,” International Journal of Technology and Design Education, Vol. 19, No. 2, pp. 221-235.

[362]Swilling, M. and E. Annecke, 2006, “Building Sustainable Neighbourhoods in South Africa: Learning from the Lynedoch Case,” Environment and Urbanization, Vol. 18, No. 2, pp. 315-332.

[363]Qasim, S. R., 2006, "Small Flow Wastewater Treatment Technology for Domestic and Special Applications," Encyclopedia of Environmental Science and Engineering (J. R. Pfafflin and E. N. Ziegler, Eds.), CRC Press, Boca Raton, FL, Vol. 2, pp. 1082 - 1093.

286 [364]The Columbia Electronic Encyclopedia, 2007, Septic Tank. The Free Dictionary, Farlex, Inc. 2012, http://encyclopedia2.thefreedictionary.com/Septic+Tank.

[365]Pro-Pump,Understanding Septic Systems. 2013, http://www.propump.com/ septic.asp.

[366]Wikipedia,2010, Scheme of Septic Tank. 2012, http://en.wikipedia.org/wiki/ File:Septic_tank_EN.svg.

[367]Sheldon Farm Septic Tank Service, I.,2012, How Septic Systems Work. Ashby, MA. 2012, http://www.pottyon.com/How_Septic_Systems_Work.html.

[368]Daimler,2005, The Mercedes-Benz Bionic Car: Streamlined and Light, Like a Fish in Water - Economical and Environmentally Friendly Thanks to the Latest Diesel Technology. Press Kit: The Mecedes-Benz Bionic Car as a Concept Vehicle. Washington. 2011, http://media.daimler.com/dcmedia/0-921-885913-1-815003-1- 0-0-815031-0-1-11702-854934-0-1-0-0-0-0-0.html?TS=1320351831755.

[369]BMW, BMW 3 Series Sedan: All the Facts. 2011, http://www.bmw.com/com/en/newvehicles/3series/sedan/2008/allfacts/engine/tec hnical_data.html.

[370]NewCarBuyingGuide.Com. 2011, http://newcarbuyingguide.com/images/articles/ reviews/bmw/BMW3Series01.jpg.

[371]Office of the Surgeon General, 2004, "The Basics of Bone in Health and Disease," Bone Health and Osteoporosis: A Report of the Surgeon General, U.S. Department of Health & Human Services.

[372]Personal Communication. Mattheck, C., Feb 16, 2012, Bionic Car. J. O'Rourke.

[373] 2011, http://newark1.com/uploaded_images/boxfish-design1-720183.jpg.

[374]2005, At a Glance: More Special Technical and Stylistic Features of the Concept Car. Washington, Daimler. 2012, http://media.daimler.com/dcmedia/0-921- 885913-1-815020-1-0-0-0-0-1-11702-854934-0-1-0-0-0-0- 0.html?TS=1329513791918.

[375]Mattheck, C., K. Bethge, A. Sauer, J. Sorensen, C. Wissner and O. Kraft, 2009, “About Cracks, Dunce Caps and a New Way to Stop Cracks,” Fatigue & Fracture of Engineering Materials & Structures, Vol. 32, pp. 484-492.

[376]CarWireFire,Car Audio. 2012, http://carwirefire.com/noise_solutions.html. 287

[377]Building Sizes that Require an Industrial Air Conditioner, Must Know How. 2011, http://www.mustknowhow.com/index.php/air-conditioning/building-sizes-that- require-an-industrial-air-conditioner.

[378]2010, Economists: Every $1 of Electricity from Coal Does $2 in Damage to U.S., inagist. 2011, http://inagist.com/greenforall/119485680350011393/Economists %3A_Every_$1_of_electricity_from_coal_does_$2_in_damage_to_U.S.

[379]2010, Philly Bagged Leaf Drive Kicks Off Nov 8th, GreenPhillyBlog.com. 2012, http://www.greenphillyblog.com/tag/2010/.

[380]Daniel, S. D. and D. D. Oakey,2009, Random Installation Carpet Tiles. USPTO. United States, Interface, Inc. 7,601,413 B2.

[381]2011, Get the Complete Picture at Greenbuild, Jetson Green. 2011, http://www.jetsongreen.com/2011/10/get-the-complete-picture-epd- greenbuild.html.

[382]Nelson, E., 2009, “How Interface Innovates with Suppliers to Create Sustainablity Solutions,” Global Business and Organizational Excellence, Vol. 28, No. 6, pp. 22-30.

[383]FLOR, I.,2012, i2TM Modular Carpet - How Nature Would Design a Floor. 2012, http://www.interfaceflor.com/Default.aspx?Section=3&Sub=11.

[384]Robbins, J.,2002, Second Nature. Smithsonian, http://www.smithsonianmag.com/ science-nature/Second_Nature.html.

[385]2012, Jacksonville Jaguars Tile, Jacksonville Jaguars: Jerseys & Memorabilia Shopping. 2012, http://www.jaguarsfootballdeals.com/fan/jacksonville-jaguars- tile.

[386]Poole, B.,2007, Biomimetics: Borrowing from Biology. Science Articles: The Naked Scientists: Science Radio & Science Podcasts, http://www.thenaked scientists.com/HTML/articles/article/biomimeticsborrowingfrombiology/.

[387]Nakajima, A., A. Fujishima, K. Hashimoto and T. Watanabe, 1999, “Preparation of Transparent Superhydrophobic Boehmite and Silica Films by Sublimation of Aluminum Acetylacetonate,” Advanced Materials, Vol. 11, No. 16, pp. 1365- 1368.

288 [388]Ultrawave,2012, Ultrasonic Technology - How Ultrasonic Cleaning Works. 2012, http://www.ultrawave.co.uk/pages/Ultrasonic-Technology-54.php.

[389]Direct Industry, Karcher: Parts Solvent Cleaning Machine (Spray). 2012, http://www.directindustry.com/prod/karcher/part-cleaning-machines-spray-5768- 212991.html#.

[390]Dean, B. and B. Bhushan, 2010, “Shark-Skin Surfaces for Fluid-Drag Reduction in Turbulent Flow: A Review,” Philosophical Transactions of the Royal Society A, Vol. 368, pp. 4775-4806.

[391]2010, Shark Skin Boat Hulls Are on the Horizon, Maritime Journal. 2012, http://www.maritimejournal.com/features101/vessel-build-and- maintenance/vessel-repair-and-maintenance/shark-skin-boat-hulls-are-on-the- horizon.

[392]A Walk in the Woods, The Huffington Post. 2012, http://i.huffpost.com/ gadgets/slideshows/203250/slide_203250_587234_small.jpg.

[393]2010, Sharklet Technologies, Inc. 2011, http://www.sharklet.com/sharklet- products/push-door-plate-skin/.

[394]2010, SharkletTM Surface Protection, Sharklet Technologies, Inc. 2012, http://www.sharklet.com/sharklet-products/sharklet-safetouch-for-commercial/.

[395]Sharklet Technologies, Inc., Sharklet Safetouch. 2012, http://www.sharklet.com/wp- content/themes/sharklet/pdfs/Sharklet-SafeTouch-Commercial-2010.pdf.

[396]Brennan, A. B., R. H. Baney, M. C. Turnage, T. G. Estes, A. W. Feinberg, L. H. Wilson and J. F. Schumacher,2010, Surface Topographies for Non-Toxic Bioadhesion Control. USPTO. United States, University of Florida Research Foundation. US 2010/1026404 A1.

[397]Sharklet Technologies, Inc., 2010, SharkletTM Surface Protection. 2012, http://www.sharklet.com/sharklet-products/sharklet-safetouch-for-commercial/.

[398]Davies, J. and D. Davies, 2010, “Origins and Evolution of Antibiotic Resistance,” Microbiology and Molecular Biology Reviews, Vol. 74, No. 3, pp. 417-433.

[399]Tezel, U. and S. G. Pavlostathis, 2012, "Role of Quaternary Ammonium Compounds on Antimicrobial Resistance in the Environment," Antimicrobial Resistance in the Environment (P. L. Keen and M. H. M. M. Montforts, Eds.), Wiley, Hoboken, NJ. 289

[400]Clorox,2012, What's in Clorox Disinfecting Bathroom Cleaner?, The Clorox Company. 2012, http://www.clorox.com/products/clorox-disinfecting-bathroom- cleaner/ingredients-and-safety/.

[401]Clorox,2012, Clorox Disinfecting Bathroom Cleaner: Usage Instructions. 2012, http://www.clorox.com/products/clorox-disinfecting-bathroom-cleaner/how-to/.

[402]Clorox,2012, Clorox Disinfecting Cleaner: About. 2012, http://www.clorox.com/products/clorox-disinfecting-bathroom-cleaner/.

[403]Clorox,2004, Material Safety Data Sheet: Clorox Disinfecting Bathroom Cleaner. Oakland, CA, Clorox Professional Products Company: 1, http://www.thecloroxcompany.com/downloads/msds/cloroxdisinfectingcleaners/cl oroxdisinfectingbathroomcleaner11-04.pdf.

[404]DOW,2012, Product Safety Assessment (PSA):Salts of Ethylenediaminetetraacetic Acid (EDTA). 2012, http://www.dow.com/productsafety/finder/edta.htm.

[405]McBain, A., A. Richard and P. Gilbert, 2002, “Possible Implications of Biocide Accumulation in the Environment on the Prevalence of Bacterial Antibiotic Resistance,” Journal of Industrial Microbiology & Biotechnology, Vol. 29, pp. 326-330.

[406]Rutala, W. A., D. J. Weber and Heathcare Infection Control Practices Advisory Committee, 2008, Guideline for Disinfection and Sterilization in Healthcare Facilities, CDC Centers for Disease Control: 1-158.

[407]EPA, 2006, Reregistration Eligibility Decision for Alkyl Dimethyl Benzyl Ammonium Chloride (ADBAC). Washington, D.C., Office of Prevention, Pesticides, and Toxic Substances, http://www.epa.gov/oppsrrd1/ REDs/adbac_red.pdf.

[408]Moyle, R. G., J. Fuchs, E. Pasquet and B. B. Marks, 2007, “Feeding Behavior, Toe Count, and the Phylogenetic Relationships Among Alcedinine Kingfishers (Alcedininae),” Journal of Avian Biology, Vol. 38, No. 3, pp. 317-326.

[409]Katzir, G. and J. M. Camhi, 1993, “Escape Response of Black Mollies (Poecilia sphenops) to Predatory Dives of a Pied Kingfisher (Ceryl rudis),” Copeia, Vol. 1993, No. 2, pp. 549-553.

[410]Amazing Photo of Kingfisher Diving, Alistair.pott. 2012, http://alistairpott.com/2009/05/20/amazing-photo-of-kingfisher-diving. 290

[411]Swiss/Japan Association for Engineers and Scientists, 2006, Train-Kingfisher, Cnet. 2012, http://news.cnet.com/2300-11395_3-6130045-5.html?tag=mncol.

[412]Lovegrove, K., 2004, Railway: Identity, Design and Culture, Laurence King Publishing, London.

[413]Hood, C. P., 2006, Shinkansen: From Bullet Train to Symbol of Modern Japan, Routledge, New York, NY.

[414]Soejima, H.,2003, Railway Technology in Japan - Challenges and Strategies. Japan Railway & Transport Review: 4-13.

[415]Kobayashi, K.,2005, JFS Bio-mimicry Interview Series: No.6 Technologies Learned from Living Things: "Shinkansen Technology Learned from an Owl?" - The Story of Eiji Nakatsu. Japan for Sustainability Newsletter. #031, http://www.japanfs.org/en_/newsletter/200503-2.html.

[416]Mashimo, S., E. Nakatsu, T. Aoki and K. Matsuo, 1997, “Attenuation and Distortion of a Compression Wave Propagating in a High-Speed Railway Tunnel,” JSME International Journal, Series B: Fluids and Thermal Engineering, Vol. 40, No. 1, pp. 51-57.

[417]High-Speed Trains, Design and the Universe. 2012, http://designanduniverse.com/ articles/high-speed_trains.php.

[418]N+P Industrial Design GmbH, 2012, Shinkansen 500 Nozomi. 2012, http://www.neumeister-partner.com/en/node/405.

[419]T, G.,2011, One Kingfisher Can Set a Rapid Speed Train Back on Track. 2012, http://www.groept.be/www/bachelor_programs/vision_of_engineering/ kingfisher/.

[420]Skutch, A. F., 1957, “Life History of the Amazon Kingfisher,” The Condor, Vol. 59, No. 4, pp. 217-229.

[421]Remsen, J. V., 1991, Community Ecology of Neotropical Kingfishers, University of California Press, Berkely, CA.

[422]Marshall, A. J., 1931, “The Azure Kingfisher,” The Emu, Vol. 31, No. 1, pp. 44-47.

[423]2011, Beak Provides Streamlining: Common Kingfisher, Ask Nature. 2012, http://www.asknature.org/strategy/4c3d00f23cae38c1d23517b6378859ee. 291

[424]Biello, D., 2002, Bullet Trains: Inside and Out, The Rosen Publishing Group, New York.

[425]EPA, 2011, Air and Radiation: Noise Pollution. 2012, http://www.epa.gov/air/noise.html.

[426]Tanaka, Y., R. Takahashi and T. Tamada, 2003, "Noise Control of Sanyo Shinkansen," The 32nd International Congress and Exposition on Noise Control Engineering, Seogwipo, Korea.

[427]OECD, Globalisation, Transport and the Environment. 2012, http://www.oecd.org/dataoecd/19/45/45095528.pdf.

[428]Horihata, K., H. Sakamoto, H. Kitabayashi and A. Ishikawa,2008, Environmentally Friendly Railway-Car Technology. Hitachi Review. 57: 18-22.

[429]Stansfeld, S. A. and M. P. Matheson, 2003, “Noise Pollution: Non-Audiory Effects on Health,” British Medical Bulletin, Vol. 68, pp. 243-257.

[430]Rheindt, F. E., 2003, “The Impact of Roads on Birds: Does Song Frequency Play a Role in Determining Susceptibility to Noise Pollution?,” Journal of Ornithology, Vol. 144, No. 3, pp. 295-306.

[431]Reijnen, R. and R. Foppen, 2006, "Chapter 12: Impact of Road Traffic on Breeding Bird Populations," Ecology of Transportation: Managing Mobility for the Environment (J. Davenport and J. L. Davenport, Eds.), Springer, Dordrecht, The Netherlands, Vol. 10, pp. 255-274.

[432]Davenport, J. and J. L. Davenport, 2006, "Introduction," Ecology of Transportation: Managing Mobility for the Environment (J. Davenport and J. L. Davenport, Eds.), Springer, Dordrecht, The Netherlands, Vol. 10.

[433]Riihimaki, J.,2007, High Speed Trains - Sokol, Nieie, 4rail.net. 2012, http://4rail.net/ref_fast_sokol.html.

[434]Miyauchi, T., T. Nagatomo, T. Tsujimura and H. Tsuchiya, 1999, “Fundamental Investigations of LCA of Shinkansen Vehicles,” Quarterly Report of the Railway Technical Research Institute (RTRI), Vol. 40, No. 4, pp. 204-209.

[435]Winkler, S.,How Can Owls Fly Silently?, How Stuff Works. 2012, http://science.howstuffworks.com/environmental/life/zoology/birds/owl-fly- silently1.htm. 292

[436]Bachmann, T. and H. Wagner, 2011, “The Three-Dimensional Shape of Serrations at Barn Owl Wings: Towards a Typical Natural Serration as a Role Model for Biomimetic Applications,” Journal of Anatomy, Vol. 219, No. 2, pp. 192-202.

[437]Conner, J.,2012, Winter Birds, Mixed Shots, SmugMug. 2012, http://nacotejack.smugmug.com/Murky-Bird-Pix/Winter-Birds-mixed- shots/1053283_YhoUo/2/50339724_rfYsU#!i=50339724&k=rfYsU.

[438]Matsumoto, M., K. Masai and T. Wajima,1999, New Technologies for Railway Trains. Hitachi Review: 134-138.

[439]2006, Pantograph Mechanism of 500 Series Shinkansen Based on Owl Feather. 2012, http://opencage.info/pics.e/large_6708.asp.

[440]Kubotake,2010, 500 Series Shinkansen Set W1 Passing Maibara Station on the "Nozomi 29" Service, Wikipedia. 2012, http://en.wikipedia.org/wiki/File: JRW_Shinkansen_Series_500_W1_sets.jpg.

[441]Koganezawa, S., S. Ohtsuka and K. Funabashi, 2011, “Linear Protrusion Structure on Carriage-Arm Surface for Reduction of Flow-Induced Carriage Vibration in Hard Disk Drives,” Microsystem Technologies, Vol. 17, No. 5-7, pp. 799-804.

[442]Lang, A. W., 2009, "Chapter 2: The Shark Skin Effect," Functional Properties of Bio-Inspired Surfaces (E. A. Favret and N. O. Fuentes, Eds.), World Scientific, Hackensack, NJ, pp. 17-38.

[443]Garcia-Mayoral, R. and J. Jimenez, 2011, “Drag Reduction by Riblets,” Philosophical Transactions of the Royal Society A, Vol. 369, No. 1940, pp. 1412- 1427.

[444]Airbus,2009, Airbus launches "Sharklet" Large Wingtip Devices for A320 Family with Commitment from Air New Zealand. 2012, http://www.airbus.com/ newsevents/news-events-single/detail/airbus-launches-sharklet-large-wingtip- devices-for-a320-family-with-commitment-from-air-new-zealan/.

[445]Vogel, S., 2010, "Moving Heat and Fluids," Bulletproof Feathers (R. Allen, Ed.), The University of Chicago Press, Chicago, pp. 110-131.

[446]Baleen Filters Pty Limited, 2011, About Baleen: Overview. 2012, http://www.baleenfilters.com/about.asp.

293 [447]Factzoo.com,2010, Baleen Whales - World's Largest Creature, Filter-Feeders. 2012, http://www.factzoo.com/mammals/worlds-largest-creatures-filter-feeding- whales.html.

[448]Baleen Filters Pty. Limited, ,2011, The Product: Overview. 2012, http://www.baleenfilters.com/product.asp.

[449]Obst, Y.,2002, Filter with Counter Flow Clearing. USPTO. United States, University of South Australia. US 6,354,442 B1.

[450]Water, Waste & Environmental Ltd, 2010, Technologies. 2012, http://ww- e.co.uk/index.php?p=1_2_Technologies.

[451]JDV Equipment Corporation, 2011, Baleen Filter. 2012, http://www.jdvequipment.com/baleen-filter.

[452]Baleen Filters Pty Limited, 2011, How to Order. 2012, http://www.baleenfilters.com/how_to_order.asp.

[453]Obst, Y.,2003, Filter with Counter Flow Clearing. European Patent Office. AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE, Baleen Filters Pty Limited. EP 0946248 B1.

[454]Calera,Carbon Dioxide Technology. 2012, http://calera.com/index.php/technology/ technology_vision/.

[455]King, H.,2012, Limestone, geology.com. 2012, http://geology.com/rocks/ limestone.shtml.

[456]Constantz, B. R., 1986, “Coral Skeleton Construction: A Physiochemically Dominated Process,” PALAIOS, Vol. 1, No. 2, pp. 152-157.

[457]Sun, H., R. Jain, K. Nguyen and J. Zuckerman, 2010, “Sialite Technology - Sustainable Alternative to Portland Cement,” Clean Technologies and Environmental Policy, Vol. 12, pp. 503-516.

[458]Schneider, M., M. Romer, M. Tschudin and H. Bolio, 2011, “Sustainable Cement Production - Present and Future,” Cement and Concrete Research, Vol. 41, No. 7, pp. 642-650.

[459]Calera,The Science: Carbonate Formation. 2012, http://calera.com/index.php/ technology/the_science/.

294 [460]Calera,Our Process. 2012, http://calera.com/index.php/technology/our_process/.

[461]Calera,Criteria Pollutant Control. 2012, http://calera.com/index.php/technology/ pollution_control/.

[462]Calera,Electrochemistry. 2012, http://calera.com/index.php/technology/ electrochemistry/.

[463]Calera,2011, Case Study: Moss Landing. 2011, http://www.calera.com/index.php/ case_studies/.

[464]Calera,2011, Frequently Asked Questions. 2011, http://www.calera.com/index.php /about_us/faqs/.

[465]Kolstad, C. and D. Young,2010, Cost Analysis of Carbon Capture and Storage for the Latrobe Valley, University of Califonia, Santa Barbara.

[466]Constantz, B. R., A. Youngs and T. C. Holland,2010, CO2-Sequestering Formed Building Materials. United States. US 7,771684 B2.

[467]Portland Cement Association, 2012, Architectural and Decorative Concrete. 2012, http://www.cement.org/decorative/overview.asp.

[468]Aubuchon Hardware, 2012, Portland Cement, 47 Lb. 2012, http://paint-and- supplies.hardwarestore.com/50-276-concrete-patch/portland-cement-221101.aspx.

[469]Nidumolu, R., C. K. Prahalad and M. R. Rangaswami,2009, Why Sustainability Is Now the Key Driver of Innovation. Harvard Business Review: 57-64.

[470]Lee, H., B. P. Lee and P. B. Messersmith, 2007, “A Reversible Wet/Dry Adhesive Inspired by Mussels and Geckos,” Nature, Vol. 448, pp. 338-341.

[471]Dolan, R.,2010, Stuck on Mussel Research to Develop Medical Adhsives. Medill Reports Chicago. Chicago, IL.

[472]Messersmith, P. B., H. Lee and B. P. Lee,2008, Biomimetic Modular Adhesive Complex: Materials, Methods and Applications Therefore. USPTO. United States. US 2008/0169059 A1.

[473]Lee, H., S. M. Dellatore, W. M. Miller and P. B. Messersmith, 2007, “Mussel- Inspired Surface Chemistry for Multifunctional Coatings,” Science, Vol. 318, pp. 426-430.

295 [474]Messersmith Research Group, 2010, Gecko-Mussel Mimetic Adhesive. Evanston, IL, Northwestern University. 2012, http://biomaterials.bme. northwestern.edu/gecko.asp.

[475]Greenemeier, L.,2008, Sticky Science: Gecko Toes Key to Adhesive that Doesn't Lose Its Tackiness. Scientific American.

[476]Greiner, C., 2010, "Gecko-Inspired Nanomaterials," Biomimetic and Bioinspired Nanomaterials (C. Kumar, Ed.), Wiley, Weinheim, Germany, pp. 1-40.

[477]Johnson, R. N.,1990, Lens-Like Radiant Energy Transmission Control Means. USPTO. United States, Radiant Optics, Inc. 4,896,656.

[478]Land, M. F., 2000, “Eyes with Mirror Optics,” Journal of Optics A: Pure and Applied Optics, Vol. 2, No. 6, pp. R44-R50.

[479]Ings, S., 2008, “Darwin 200: An Eye for the Eye,” Nature, Vol. 456, pp. 304-209.

[480]Lohmann, K. J., 2010, “Magnetic-Field Perception,” Nature, Vol. 464, pp. 1140- 1142.

[481]Johnson, R. N.,2004, Radiant Energy Source Systems, Devices, and Methods Capturing, Controlling, or Recycling Gas Flows. USPTO. United States. US 2004/0255927 A1.

[482]Drillspot,2012, Hot Zone Wall Mount Radiant Heater. 2012, http://www.drillspot.com/products/1410875/Hot_Zone_HZE15120SW_Electric_I nfrared_heater.

[483]HotZone,2008, HotZone: History. Sauk Rapids, MN, Schaefer Ventilation Equipment. 2012, http://www.radiantoptics.com/History.htm.

[484]Schaefer Ventilation Equipment, 2008, Hotzone Radiant Heaters. 2012, http://www.schaeferfan.com/HOTZONE_RADIANT_HEATERS_C1983.cfm.

[485]Giant Amazon Water Lily Gaining Size, The Living Rainforest. 2012, http://www.livingrainforest.org/news/giant-amazon-water-lily-gaining-size/.

[486]Ramakrishnan, R. and R. R. Konwar,2010, Wet, Wild, and Wonderful, The Hindu. 2012, http://www.thehindu.com/life-and-style/kids/article98282.ece.

[487]BBC,2004, Crystal Palace. London. 2012, http://www.bbc.co.uk/london/content/ articles/2004/07/27/history_feature.shtml. 296

[488]Wikipedia,2012, The Crystal Palace. 2012, http://en.wikipedia.org/wiki/ The_Crystal_Palace.

[489]2010, Crystal Palace in London, Ask Nature. 2011, http://www.asknature.org/ product/a13b2a14313fcc7123e827269a1d8a73#changeTab.

[490]Leaves Given Structural Support: Giant Water-Lily Ask Nature. 2011, http://www.asknature.org/strategy/902666afb8d8548320ae0afcd54d02ae.

[491]Attenborough, D., 1995, The Private Life of Plants: A Natural History of Plant Behaviour, Princeton University Press.

[492]2012, 30" Tulip Stem, GD International China Trade Online. 2012, http://www.gd- wholesale.com/chinaproduct/mf23d/av1191to1bv/30-tulip-stem-m59743.html.

[493]Hossler, F.,Head of a Human Femur, Science Photo Library. 2012, http://www.sciencephoto.com/media/118847/enlarge.

[494]2011, The Beauty of the Eiffel Tower, Beautiful Tourism. 2012, http://www.idntourism.com/the-beauty-of-eiffel-tower/.

[495]Gorb, E. and S. Gorv, 2002, “Contact Separation Force of the Fruit Burrs in Four Plant Species to Dispersal by Mechanical Interlocking,” Plant Physiology and Biochemistry, Vol. 40, pp. 373-381.

[496]2012, http://www.forestryimages.org/images/3072x2048/5392712.jpg.

[497]Knight, D. J.,2009, Inspired by Nature. New York State Conservationist, New York Department of Environmental Conservation. 2012.

[498]de Mestral, G. 1961, Separable Fastening Device. USPTO. United States, International Velcro Company. 3,009,235.

[499]Use of Velcro, Interesting Topics. 2012, http://www.interestingtopics.net/use-of- velcro-id-342.

[500]Anderson, T. E.,2005, Velcro Being Pulled Apart (94x), Small World Nikon. 2012, http://www.nikonsmallworld.com/gallery/year/2005/21.

[501]Gupta, S. M. and P. Veerakamolmal, 2000, "Environmental Issues: Reuse and Recycling in Manufacturing Systems," Encyclopedia of Production (P. M. Swamidass, Ed.), Kluwer Academic Publishers, Norwell, MA, pp. 192-197. 297

[502]Justel, D., R. Vidal and M. Chiner, 2005, "TRIZ Applied for Eco-Innovation in Design for Disassembly," 1st IFIP TC-5 Working Conference on CAI, Ulm, Germany.

[503]2011, Button Button Whos Got the Button. Norfolk, MA, In the Loop. 2012, http://keepyourneedleshappy.com/inspiration-of-the-month/button-button-whos- got-the-button/.

[504]2012, Stock Photo - Detail of a Green Zipper (Slide Fastener) on White Background, 123RF, http://www.123rf.com/photo_4421188_detail-of-a-green- zipper-slide-fastener-on-white-background.html.

[505]2009, Science of the Shoelace, Homeschooling 100 Digits, http://100digits.com/?p=1743.

[506]Chakrabarti, A. and L. H. Shu, 2010, “Biologically Inspired Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, pp. 453-454.

[507]Coelho, D. A. and C. A. M. Versos, 2011, “A Comparative Analysis of Six Bionic Design Methods,” International Journal of Design Engineering, Vol. 4, No. 2, pp. 114-131.

[508]Vandevenne, D., P.-A. Verhaegen, S. Dewulf and J. R. Duflou, 2012, "Automatically Populating the Biomimicry Taxonomy for Scalable Systematic Biologically-Inspired Design," IDETC/CIE 2012, Chicago, IL, DETC2012- 70928.

[509]Glier, M. W., J. Tsenn, J. S. Linsey and D. A. McAdams, 2012, "Evaluating the Directed Method for Bioinspired Design," IDETC/CIE 2012, Chicago, IL, DETC2012-71511.

[510]Forbes, P., 2005, "Something New Under the Sun," The Gecko's Foot: Bio- inspiration: Engineering New Materials from Nature, W.W. Norton & Company, Inc., New York, NY, pp. 1-28.

[511]Gruber, P., D. Bruckner, C. Hellmich, H.-B. Schmiedmayer, H. Stachelberger and I. C. Gebeshuber, 2011, "Preface," Biomimetics - Materials, Structures, and Processes, Springer, New York.

[512]Jenkins, C. H. M., 2005, "Preface," Compliant Structures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA. 298

[513]Yang, H. T. Y., C.-H. Lin, D. Bridges, C. J. Randall and P. K. Hansma, 2010, “Bio- Inspired Passive Actuator Simulating an Abalone Shell Mechanism for Structural Control,” Smart Materials and Structures, Vol. 19, No. 10.

[514]Sartori, J., U. Pal and A. Chakrabarti, 2010, “A Methodology for Supporting "Transfer" in Biomimetic Design,” Artificial Intelligence for Engineering Design, Analysis, and Manufacturing, Vol. 24, pp. 483-505.

[515]Tarascon, J.-M., 2008, “Towards Sustainable and Renewable Systems for Electrochemical Energy Storage,” ChemSUSChem, Vol. 1, No. 8-9, pp. 777-779.

[516]Vincent, J. F. V., 2005, "Compliant Structures and Materials in Animals," Compliant Structures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA, pp. 3-20.

[517]Jenkins, C. H. M., 2005, "Design of Compliant Structures," Compliant Structures in Nature and Engineering (C. H. M. Jenkins, Ed.), WIT Press, Billerica, MA, pp. 247-261.

[518]Glier, M. W., J. Tsenn, J. S. Linsey and D. A. McAdams, 2011, "Methods for Supporting Bioinspired Design," International Mechanical Engineering Congress & Exposition, Denver, Colorado, IMECE2011-63247.

[519]Meijer, K., J. C. Moreno and H. H. C. M. Savelberg, 2006, "Biological Mechanisms as Models for Mimicking: Sarcomere Design, Arrangement and Muscle Function," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 41-56.

[520]Ummat, A., A. Dubey and C. Mavroidis, 2006, "Bio-Nanorobotics: A Field Inspired by Nature," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 201-227.

[521]Bar-Cohen, Y., 2006, "Artificial Muscles Using Electroactive Polymer," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 267-290.

[522]Szema, R. and L. P. Lee, 2006, "Biologically Inspired Optical Systems," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 291-308.

299 [523]Carlson, J., S. Ghaey, S. Moran, C. A. Tran and D. L. Kaplan, 2006, "Biological Materials in Engineering Mechanisms," Biomimetics:Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 365-379.

[524]Lou, Z., S. Hosoe and M. Ito, 2006, "Biomimetic and Biologically Inspired Control," Biomimetics: Biologically Inspired Technologies (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 399-425.

[525]Plamondon, N. and M. Nahon, 2009, “A Trajectory Tracking Controller for an Underwater Hexapod Vehicle,” Bioinspiration and Biomimetics, Vol. 4, No. 3, pp. 036005.

[526]Armour, R., K. Paskins, A. Bowyer, J. Vincent and W. Megill, 2007, “Jumping Robots: A Biomimetic Solution to Locomotion Across Rough Terrain,” Bioinspiration and Biomimetics, Vol. 2, No. 3, pp. S65-S82.

[527]Dabiri, J. O., 2007, “Renewable Fluid Dynamic Energy Derived from Aquatic Animal Locomotion,” Bioinspiration and Biomimetics, Vol. 2, No. 3, pp. L1-L3.

[528]Gopal, V. and M. J. Z. Hartmann, 2007, “Using Hardware Models to Quantify Sensory Data Acquisition Across the Rat Vibrissal Array,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S135-S145.

[529]Nakrani, S. and C. Tovey, 2007, “From Honeybees to Internet Servers: Biomimicry for Distributed Management of Internet Hosting Centers,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. S182-S197.

[530]Margerie, E. d., J. Mouret, S. Doncieux and J.-A. Meyer, 2007, “Artificial Evolution of the Morphology and Kinematics in a Flapping-Wing Mini-UAV,” Bioinspiration and Biomimetics, Vol. 2, No. 4, pp. 65-82.

[531]Bartol, I., M. Gordon, P. Webb, D. Weihs and M. Gharib, 2008, “Evidence of Self- Correcting Spiral Flows in Swimming Boxfishes,” Bioinspiration and Biomimetics, Vol. 3, No. 1, pp. 014001.

[532]Myrick, A., K.-C. Park, J. R. Hetling and T. C. Baker, 2008, “Real-Time Odor Discrimination Using a Bioelectronic Sensor Array Based on the Insect Electroantennogram,” Bioinspiration and Biomimetics, Vol. 3, No. 4, pp. 046006.

[533]Sarikaya, M., J. Liu and I. A. Aksay, 1995, "Nacre: Properties, Crystallography, Morphology, and Formation," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 35-90.

300 [534]Mann, S., 1995, "Biomineralization, the Inorganic-Organic Interface, and Crystal Engineering," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 91-116.

[535]Calvert, P., 1995, "Biomimetic Ceramics and Hard Composites," Biomimetics: Design and Processing of Materials (M. Sarikaya and I. A. Aksay, Eds.), AIP Press, Woodbury, New York, pp. 145-161.

[536]Vattam, S. S., M. Helms and A. K. Goel, 2010, "Biologically Inspired Design: A Macrocognitive Account," IDETC/CIE 2010, Montreal, Canada, DETC2010- 28567.

[537]Potter, K. A., B. Gui and J. R. Capadona, 2012, "Biomimicry at the Cell-Material Interface," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 95-129.

[538]Fish, F. E., A. J. Smits, H. Haj-Hariri, H. Bart-Smith and T. Iwasaki, 2012, "Biomimetic Swimmer Inspired by the Manta Ray," Biomimetics: Nature-Based Innovation (Y. Bar-Cohen, Ed.), CRC Press, Boca Raton, FL, pp. 495-523.

[539]Weiner, S. and P. Zaslansky, 2004, "Structure-Mechanical Function Relations in Bones and Death," Learning from Nature How to Design New Implantable Biomaterials: From Biomineralization Fundamentals to Biomimetic Materials and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. 3-13.

[540]Aizenberg, J. and G. Hendler, 2004, "Learning from Marine Creatures How to Design Micro-Lenses," Learning from Nature: How to Design New Implantable Biomaterials: From Biomineralization Fundamentals to Biomimetic Materials and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, Vol. 171, pp. 151-166.

[541]Isaacson, A.,2009, Nature Inspiring Green Design for Planes, Train, Autos & More. Popular Mechanics.

[542]Freedman, M.,2010, Nature is the Model Factory. Newsweek.

[543]Offner, D. H., 1995, "Introduction to Design Homology," Design Homology: An Introduction to Bionics, David Offner, Urbana, Illinois, pp. 1-12.

[544]Reis, R. L., 2004, "Preface," Learning from Nature How to Design New Implantable Biomaterials: From Biomimeralization Fundamentals to Biomimetic Materials

301 and Processing Routes (R. L. Reis and S. Weiner, Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands, pp. xi-xiv.

[545]Biomimicry Institute, 2010, B.I.A.S. Biologically Inspired Acoustic Systems, Ask Nature. 2010, http://www.asknature.org/product/0fdee3b68d08f0750097 11803dc93c16.

[546]Biomimicry Institute, 2009, bioBASE Mooring System, Ask Nature. 2010, http://www.asknature.org/product/0af0cefd471050bcc5de19367aae3237.

[547]Biomimicry Institute, 2010, BioFriend Anti-Microbial, Ask Nature. 2010, http://www.asknature.org/product/4535c47d225d0585cd4139133629f19d.

[548]Biomimicry Institute, 2010, Bioinspired Adhesive Tape, Ask Nature. 2010, http://www.asknature.org/product/2dbddc320a256b0c84fb3ef7b9131e1d.

[549]Biomimicry Institute, 2010, Bioinspired Material Adhesive, Ask Nature. 2010, http://www.asknature.org/product/65bba2940a2ce1e9de9f0e2e0164ced3.

[550]Biomimicry Institute, 2010, Biomatrica Sample Matrix, Ask Nature. 2010, http://www.asknature.org/product/df78111ca0805a840a4b9a32628d9c79.

[551]Biomimicry Institute, 2010, Biopolymers, Ask Nature. 2010, http://www.asknature.org/product/a3dda50e918bfd34b509b96f2ca62979.

[552]Biomimicry Institute, 2008, BioSTREAM Tidal Energy, Ask Nature. 2010, http://www.asknature.org/product/a3676b91b1431c1727ab8517d1575f5e.

[553]Biomimicry Institute, 2010, Capillary Faucets, Ask Nature. 2010, http://www.asknature.org/product/7a6f6ce2f13399d9f9dcbc2bfae10d1b.

[554]Biomimicry Institute, 2010, Carbon Dioxide-Based Plastics, Ask Nature. 2010, http://www.asknature.org/product/c3143ba9e46e4adafb11645a7f1b7b95.

[555]Biomimicry Institute, 2010, ChromaFlair Color-Shifting Paints, Ask Nature. 2010, http://www.asknature.org/product/b3a96e92b68e9de4226c40e058409d30.

[556]Biomimicry Institute, 2010, Dew Bank Bottle, Ask Nature. 2010, http://www.asknature.org/product/313a2fdcdc072fbfc7ae7e69962eab80.

[557]Biomimicry Institute, 2010, Dye Solar Cell Technology, Ask Nature. 2010, http://www.asknature.org/product/313a2fdcdc072fbfc7ae7e69962eab80.

302 [558]Biomimicry Institute, 2010, Wastewater Treatment Without Chemicals, Ask Nature. 2010, http://www.asknature.org/product/d0a39e225aea22ee036e9602369c6ee0.

[559]Biomimicry Institute, 2010, FLOWE Wind Farm Design, Ask Nature. 2010, http://www.asknature.org/product/20015e39f852cfc1382828afef82b916.

[560]Biomimicry Institute, 2010, Fog-Catching Materials, Ask Nature. 2010, http://www.asknature.org/product/ce46c846e11fb2e99eff7f1143df3bd3.

[561]Biomimicry Institute, 2009, Goatek Traction Hiking Sole, Ask Nature. 2010, http://www.asknature.org/product/e53fed91dd6e8d4a348f3454493d4c90.

[562]Biomimicry Institute, 2009, GreenShield Fabric Finish, Ask Nature. 2010, http://www.asknature.org/product/28dac96ae850e0972f1a61db94844994.

[563]Biomimicry Institute, 2010, GROW Solar Ivy, Ask Nature. 2010, http://www.asknature.org/product/256b9f497821497773d9f0c442ab367a.

[564]Biomimicry Institute, 2010, Heliotrope Sun-Tracking System, Ask Nature. 2010, http://www.asknature.org/product/347aedb6508fed4c9a373bf3fc7eca65.

[565]Biomimicry Institute, 2009, Humidity Responsive Fibers, Ask Nature. 2010, http://www.asknature.org/product/f09a2bc54034f51a9084bd423524cb60.

[566]Biomimicry Institute, 2010, Humidity Sensor, Ask Nature. 2010, http://www.asknature.org/product/971a4991263e78d44efcbe5a3053d159.

[567]Biomimicry Institute, 2009, IntAct Labs, LLC Biosensor, Ask Nature. 2010, http://www.asknature.org/product/7084aacc31039ca27ab8fd02ffbbcd98.

[568]Biomimicry Institute, 2009, Joinlox, Ask Nature. 2010, http://www.asknature.org/product/0e663bb73680a395ec14d29d02f6a5ae.

[569]Biomimicry Institute, 2009, Kalundborg Industrial Symbiosis, Ask Nature. 2010, http://www.asknature.org/product/b08979c20b2d379a8af64fa83826db34.

[570]Biomimicry Institute, 2010, LOCUST Visual Collision Detector, Ask Nature. 2010, http://www.asknature.org/product/4912392abba072c917725028dc47c2c7.

[571]Biomimicry Institute, 2008, Lotus Clay Roofing Tiles, Ask Nature. 2010, http://www.asknature.org/product/aaef0c685b83f9240a61863b8a27b81e.

303 [572]Biomimicry Institute, 2008, Lotusan Paint, Ask Nature. 2010, http://www.asknature.org/product/6b8342fc3e784201e4950dbd80510455.

[573]Biomimicry Institute, 2010, Mechanically Adaptive Polymer Nanocomposites, Ask Nature. 2010, http://www.asknature.org/product/4482a19d387bc20978550e 7490799fbd.

[574]Biomimicry Institute, 2010, Medical Implant Coating, Ask Nature. 2010, http://www.asknature.org/product/c16a58d2f0fb8a4b6098ef89f1fbce29.

[575]Biomimicry Institute, 2010, Microfluidic Silk Assembly, Ask Nature. 2010, http://www.asknature.org/product/db078b01d8a8cda426c5d81317034080.

[576]Biomimicry Institute, 2010, Mincor TX TT Textile Coating, Ask Nature. 2010, http://www.asknature.org/product/b0b23316d7587d93d3e5891df168d19e.

[577]Biomimicry Institute, 2010, Morphotex Structural Colored Fibers, Ask Nature. 2010, http://www.asknature.org/product/4c0e62f66bcccabf55a1f189da30acb3.

[578]Biomimicry Institute, 2010, MothEYE and MARAG Films, Ask Nature. 2010, http://www.asknature.org/product/b7fd4cfaf7380bb1f00e8759cfddc7e6.

[579]Biomimicry Institute, 2010, NanoSphere Fabric Finish, Ask Nature. 2010, http://www.asknature.org/product/600e2a50746fa6339870554b2a7a36fd.

[580]Biomimicry Institute, 2010, ORNILUX, Ask Nature. 2010, http://www.asknature.org/product/077e9d44e8e12f039458729f8de1ada9.

[581]Biomimicry Institute, 2010, Pangolin Backpack, Ask Nature. 2010, http://www.asknature.org/product/cb31d079e6398e2c9e78e92443940a11.

[582]Biomimicry Institute, 2010, PAX Water Mixer, Ask Nature. 2010, http://www.asknature.org/product/1a119e978284900963298a0aac59a120.

[583]Biomimicry Institute, 2009, PaxFan Fans, Ask Nature. 2010, http://www.asknature.org/product/91eebf530a565f2024b894d7dd661733.

[584]Biomimicry Institute, 2010, Phillips Head Protection Systems (PHPS), Ask Nature. 2010, http://www.asknature.org/product/52b0b0cd3c9afbf7d6cbb8ed83aac6af.

[585]Biomimicry Institute, 2010, Platelet Technology Leak Sealer, Ask Nature. 2010, http://www.asknature.org/product/897d0e619743c41d4cbb528e1a8bac95.

304 [586]Biomimicry Institute, 2010, Polar Thermos Cozy, Ask Nature. 2010, http://www.asknature.org/product/2d8d7cd3ed6cb2ee83704bf7ebf161dc.

[587]Biomimicry Institute, 2010, Power Plastic Solar Cell Technology, Ask Nature. 2010, http://www.asknature.org/product/a21fcbc8ff5a053c793164e3fdffc249.

[588]Biomimicry Institute, 2010, PureBond Technology, Ask Nature. 2010, http://www.asknature.org/product/22aa5601fcdb68b5d2dc9e3d3a22f7f1.

[589]Biomimicry Institute, 2008, Self-Cleaning Fabric, Ask Nature. 2010, http://www.asknature.org/product/a0c03b1905b495f3b8d65728b09c8ae3.

[590]Biomimicry Institute, 2008, Self-Cleaning Optical Coatings, Ask Nature. 2010, http://www.asknature.org/product/ea0c697201031255bfcbc2f6a22a7a99.

[591]Biomimicry Institute, 2010, Self-Cleaning Surface, Ask Nature. 2010, http://www.asknature.org/product/a0c03b1905b495f3b8d65728b09c8ae3.

[592]Biomimicry Institute, 2008, Soil-Moving Equipment, Ask Nature. 2010, http://www.asknature.org/product/012cdf8145f7d47924ce686a9fb033a0.

[593]Biomimicry Institute, 2010, Solar Water Still and Pump, Ask Nature. 2010, http://www.asknature.org/product/1c404f66d0f4746f5f4810a2a92ecf1c.

[594]Biomimicry Institute, 2010, Stabilitech Vaccine Stabilization Technology, Ask Nature. 2010, http://www.asknature.org/product/107c8e637bde3ccd25f19 fc97ce20f7b.

[595]Biomimicry Institute, 2010, Swiss Re Building, Ask Nature. 2010, http://www.asknature.org/product/b8b39318c66e6c873137da2910785413.

[596]Biomimicry Institute, 2010, Sycamore Ceiling Fan, Ask Nature. 2010, http://www.asknature.org/product/dd0648940077b68055b2a01cac1f50cc.

[597]Biomimicry Institute, 2010, VitRIS and HydRIS Vaccine Stabilization Technologies, Ask Nature. 2010, http://www.asknature.org/product/fd6de0964dc5224631 c8d67aa3713937.

[598]Biomimicry Institute, 2010, Water-Repellent Ship Coatings. 2010, http://www.asknature.org/product/b554d0e2babb24b9bb6858b889ea8178.

[599]Mengesha, T. E., R. R. Vallance and R. Mittal, 2011, “Stiffness of Desiccating Insect Wings,” Bioinspiration and Biomimetics, Vol. 6, No. 1, pp. 014001. 305

[600]Chiadini, F., V. Fiumara, A. Scaglione and A. Lakhtakia, 2011, “Simulation and Analysis of Prismatic Bioinspired Compound Lenses for Solar Cells: II. Multifrequency Analysis,” Bioinspiration and Biomimetics, Vol. 6, No. 1, pp. 014002.

[601]Myrick, A. and T. Baker, 2011, “Locating a Compact Odor Source Using a Four- Channel Insect Electroantennogram Sensor,” Bioinspiration and Biomimetics, Vol. 6, No. 1, pp. 016002.

[602]French, J. J. R. and B. M. Ahmed, 2010, “Commentary: The Challenge of Biomimetic Design for Carbon-Neutral Buildings Using Termite Engineering,” Insect Science, Vol. 17, No. 2, pp. 154-162.

[603]Talk, T.,2011, A Robot that Flies Like a Bird, http://www.youtube.com/ watch?v=Fg_JcKSHUtQ&feature=player_embedded&noredirect=1.

[604]Bhushan, B. and M. Nosonovsky, 2010, “The Rose Petal Effect and the Modes of Superhydrophobicity,” Philosophical Transactions of the Royal Society A, Vol. 368, No. 1929, pp. 4713-4728.

[605]NIOSCH,2010, Trichloroethylene, Centers for Disease Control and Prevention (CDC). 2012, http://www.cdc.gov/niosh/npg/npgd0629.html.

[606]DOW,2010, Chlorinated Solvents Biodegradability. DOW Answer Center, The DOW Chemical Company. 2012, https://dow-answer.custhelp.com/app/ answers/detail/a_id/1338/kw/chlorinated%20solvents%20biodegradability.

306