Morphology and Mathematics. by D'arcy Wentworth Thompson. The
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CHECKLIST and BIOGEOGRAPHY of FISHES from GUADALUPE ISLAND, WESTERN MEXICO Héctor Reyes-Bonilla, Arturo Ayala-Bocos, Luis E
ReyeS-BONIllA eT Al: CheCklIST AND BIOgeOgRAphy Of fISheS fROm gUADAlUpe ISlAND CalCOfI Rep., Vol. 51, 2010 CHECKLIST AND BIOGEOGRAPHY OF FISHES FROM GUADALUPE ISLAND, WESTERN MEXICO Héctor REyES-BONILLA, Arturo AyALA-BOCOS, LUIS E. Calderon-AGUILERA SAúL GONzáLEz-Romero, ISRAEL SáNCHEz-ALCántara Centro de Investigación Científica y de Educación Superior de Ensenada AND MARIANA Walther MENDOzA Carretera Tijuana - Ensenada # 3918, zona Playitas, C.P. 22860 Universidad Autónoma de Baja California Sur Ensenada, B.C., México Departamento de Biología Marina Tel: +52 646 1750500, ext. 25257; Fax: +52 646 Apartado postal 19-B, CP 23080 [email protected] La Paz, B.C.S., México. Tel: (612) 123-8800, ext. 4160; Fax: (612) 123-8819 NADIA C. Olivares-BAñUELOS [email protected] Reserva de la Biosfera Isla Guadalupe Comisión Nacional de áreas Naturales Protegidas yULIANA R. BEDOLLA-GUzMáN AND Avenida del Puerto 375, local 30 Arturo RAMíREz-VALDEz Fraccionamiento Playas de Ensenada, C.P. 22880 Universidad Autónoma de Baja California Ensenada, B.C., México Facultad de Ciencias Marinas, Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja California, Carr. Tijuana-Ensenada km. 107, Apartado postal 453, C.P. 22890 Ensenada, B.C., México ABSTRACT recognized the biological and ecological significance of Guadalupe Island, off Baja California, México, is Guadalupe Island, and declared it a Biosphere Reserve an important fishing area which also harbors high (SEMARNAT 2005). marine biodiversity. Based on field data, literature Guadalupe Island is isolated, far away from the main- reviews, and scientific collection records, we pres- land and has limited logistic facilities to conduct scien- ent a comprehensive checklist of the local fish fauna, tific studies. -
Claus Kahlert and Otto E. Rössler Institute for Physical and Theoretical Chemistry, University of Tübingen Z. Naturforsch
Chaos as a Limit in a Boundary Value Problem Claus Kahlert and Otto E. Rössler Institute for Physical and Theoretical Chemistry, University of Tübingen Z. Naturforsch. 39a, 1200- 1203 (1984); received November 8, 1984 A piecewise-linear. 3-variable autonomous O.D.E. of C° type, known to describe constant- shape travelling waves in one-dimensional reaction-diffusion media of Rinzel-Keller type, is numerically shown to possess a chaotic attractor in state space. An analytical method proving the possibility of chaos is outlined and a set of parameters yielding Shil'nikov chaos indicated. A symbolic dynamics technique can be used to show how the limiting chaos dominates the behavior even of the finite boundary value problem. Reaction-diffusion equations occur in many dis boundary conditions are assumed. This result was ciplines [1, 2], Piecewise-linear systems are especially obtained by an analytical matching method. The amenable to analysis. A variant to the Rinzel-Keller connection to chaos theory (Smale [6] basic sets) equation of nerve conduction [3] can be written as was not evident at the time. In the following, even the possibility of manifest chaos will be demon 9 ö2 — u u + p [- u + r - ß + e (ii - Ö)], strated. o t oa~ In Fig. 1, a chaotic attractor of (2) is presented. Ö The flow can be classified as an example of "screw- — r = - e u + r , (1) 0/ type-chaos" (cf. [7]). A second example of a chaotic attractor is shown in Fig. 2. A 1-D projection of a where 0(a) =1 if a > 0 and zero otherwise; d is the 2-D cross section through the chaotic flow in a threshold parameter. -
D'arcy Wentworth Thompson
D’ARCY WENTWORTH THOMPSON Mathematically trained maverick zoologist D’Arcy Wentworth Thompson (May 2, 1860 –June 21, 1948) was among the first to cross the frontier between mathematics and the biological world and as such became the first true biomathematician. A polymath with unbounded energy, he saw mathematical patterns in everything – the mysterious spiral forms that appear in the curve of a seashell, the swirl of water boiling in a pan, the sweep of faraway nebulae, the thickness of stripes along a zebra’s flanks, the floret of a flower, etc. His premise was that “everything is the way it is because it got that way… the form of an object is a ‘diagram of forces’, in this sense, at least, that from it we can judge of or deduce the forces that are acting or have acted upon it.” He asserted that one must not merely study finished forms but also the forces that mold them. He sought to describe the mathematical origins of shapes and structures in the natural world, writing: “Cell and tissue, shell and bone, leaf and flower, are so many portions of matter and it is in obedience to the laws of physics that their particles have been moved, molded and conformed. There are no exceptions to the rule that God always geometrizes.” Thompson was born in Edinburgh, Scotland, the son of a Professor of Greek. At ten he entered Edinburgh Academy, winning prizes for Classics, Greek Testament, Mathematics and Modern Languages. At seventeen he went to the University of Edinburgh to study medicine, but two years later he won a scholarship to Trinity College, Cambridge, where he concentrated on zoology and natural science. -
Updated Checklist of Marine Fishes (Chordata: Craniata) from Portugal and the Proposed Extension of the Portuguese Continental Shelf
European Journal of Taxonomy 73: 1-73 ISSN 2118-9773 http://dx.doi.org/10.5852/ejt.2014.73 www.europeanjournaloftaxonomy.eu 2014 · Carneiro M. et al. This work is licensed under a Creative Commons Attribution 3.0 License. Monograph urn:lsid:zoobank.org:pub:9A5F217D-8E7B-448A-9CAB-2CCC9CC6F857 Updated checklist of marine fishes (Chordata: Craniata) from Portugal and the proposed extension of the Portuguese continental shelf Miguel CARNEIRO1,5, Rogélia MARTINS2,6, Monica LANDI*,3,7 & Filipe O. COSTA4,8 1,2 DIV-RP (Modelling and Management Fishery Resources Division), Instituto Português do Mar e da Atmosfera, Av. Brasilia 1449-006 Lisboa, Portugal. E-mail: [email protected], [email protected] 3,4 CBMA (Centre of Molecular and Environmental Biology), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal. E-mail: [email protected], [email protected] * corresponding author: [email protected] 5 urn:lsid:zoobank.org:author:90A98A50-327E-4648-9DCE-75709C7A2472 6 urn:lsid:zoobank.org:author:1EB6DE00-9E91-407C-B7C4-34F31F29FD88 7 urn:lsid:zoobank.org:author:6D3AC760-77F2-4CFA-B5C7-665CB07F4CEB 8 urn:lsid:zoobank.org:author:48E53CF3-71C8-403C-BECD-10B20B3C15B4 Abstract. The study of the Portuguese marine ichthyofauna has a long historical tradition, rooted back in the 18th Century. Here we present an annotated checklist of the marine fishes from Portuguese waters, including the area encompassed by the proposed extension of the Portuguese continental shelf and the Economic Exclusive Zone (EEZ). The list is based on historical literature records and taxon occurrence data obtained from natural history collections, together with new revisions and occurrences. -
A Method of Constructing Phyllotaxically Arranged Modular Models by Partitioning the Interior of a Cylinder Or a Cone
A method of constructing phyllotaxically arranged modular models by partitioning the interior of a cylinder or a cone Cezary St¸epie´n Institute of Computer Science, Warsaw University of Technology, Poland [email protected] Abstract. The paper describes a method of partitioning a cylinder space into three-dimensional sub- spaces, congruent to each other, as well as partitioning a cone space into subspaces similar to each other. The way of partitioning is of such a nature that the intersection of any two subspaces is the empty set. Subspaces are arranged with regard to phyllotaxis. Phyllotaxis lets us distinguish privileged directions and observe parastichies trending these directions. The subspaces are created by sweeping a changing cross-section along a given path, which enables us to obtain not only simple shapes but also complicated ones. Having created these subspaces, we can put modules inside them, which do not need to be obligatorily congruent or similar. The method ensures that any module does not intersect another one. An example of plant model is given, consisting of modules phyllotaxically arranged inside a cylinder or a cone. Key words: computer graphics; modeling; modular model; phyllotaxis; cylinder partitioning; cone partitioning; genetic helix; parastichy. 1. Introduction Phyllotaxis is the manner of how leaves are arranged on a plant stem. The regularity of leaves arrangement, known for a long time, still absorbs the attention of researchers in the fields of botany, mathematics and computer graphics. Various methods have been used to describe phyllotaxis. A historical review of problems referring to phyllotaxis is given in [7]. Its connections with number sequences, e.g. -
Art and Engineering Inspired by Swarm Robotics
RICE UNIVERSITY Art and Engineering Inspired by Swarm Robotics by Yu Zhou A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Approved, Thesis Committee: Ronald Goldman, Chair Professor of Computer Science Joe Warren Professor of Computer Science Marcia O'Malley Professor of Mechanical Engineering Houston, Texas April, 2017 ABSTRACT Art and Engineering Inspired by Swarm Robotics by Yu Zhou Swarm robotics has the potential to combine the power of the hive with the sen- sibility of the individual to solve non-traditional problems in mechanical, industrial, and architectural engineering and to develop exquisite art beyond the ken of most contemporary painters, sculptors, and architects. The goal of this thesis is to apply swarm robotics to the sublime and the quotidian to achieve this synergy between art and engineering. The potential applications of collective behaviors, manipulation, and self-assembly are quite extensive. We will concentrate our research on three topics: fractals, stabil- ity analysis, and building an enhanced multi-robot simulator. Self-assembly of swarm robots into fractal shapes can be used both for artistic purposes (fractal sculptures) and in engineering applications (fractal antennas). Stability analysis studies whether distributed swarm algorithms are stable and robust either to sensing or to numerical errors, and tries to provide solutions to avoid unstable robot configurations. Our enhanced multi-robot simulator supports this research by providing real-time simula- tions with customized parameters, and can become as well a platform for educating a new generation of artists and engineers. The goal of this thesis is to use techniques inspired by swarm robotics to develop a computational framework accessible to and suitable for both artists and engineers. -
(12) United States Patent (10) Patent No.: US 6,948,910 B2 Polacsek (45) Date of Patent: Sep
USOO694891 OB2 (12) United States Patent (10) Patent No.: US 6,948,910 B2 PolacSek (45) Date of Patent: Sep. 27, 2005 (54) SPIRAL-BASED AXIAL FLOW DEVICES William C. Elmore, Mark A. Heald- “Physics of Waves” (C) 1969 PP 5–35, 203–205, 234-235, ISBN-0486 64926–1, (76) Inventor: Ronald R. Polacsek, 73373 Joshua Dover Publ., Canada. Tree St., Palm Desert, CA (US) 92260 A.A. Andronov, AA. Viti, “Theory of Oscillators.” (C) 1966, (*) Notice: Subject to any disclaimer, the term of this pp. 56–58, 199-200, ISBDN-0486-65508–3, Dover Pub patent is extended or adjusted under 35 lishing, Canada. U.S.C. 154(b) by 375 days. Erik Anderson et al., Journal of Experimental Biology, “The Boundary Layer of Swimming Fish' pp 81-102 (C) Dec. 5, (21) Appl. No.: 10/194,386 2000, (C) The Company of Biologists, Great Britain. Stephen Strogatz, “Nonlinear Dynamics and Chaos” (C) 1994 (22) Filed: Jul. 12, 2002 pp. 262-279, ISBDN 0-7382-0453–6 (C) Perseus Books, (65) Prior Publication Data USA. US 2004/0009063 A1 Jan. 15, 2004 (Continued) (51) Int. Cl. ................................................ B64C 11/18 (52) U.S. Cl. ........................................ 416/1; 416/227 R Primary Examiner Edward K. Look (58) Field of Search ................................. 416/1, 227 R, Assistant Examiner Richard Edgar 416/227A, 223 R, 223 A (57) ABSTRACT (56) References Cited Axial flow devices using rigid spiral band profiled blade U.S. PATENT DOCUMENTS catenaries attached variably along and around an axially elongated profiled hub, of axially oriented profile Section 547,210 A 10/1895 Haussmann 1864,848 A 6/1932 Munk .................... -
Olfactory Organs in the Deep Sea Hatchetfish <I>Sternoptyx
NOTES BULLETIN OF MARINE SCIENCE, 53(3): 1163-1167, 1993 OLFACTORY ORGANS IN THE DEEP SEA HATCHETFISH STERNOPTYX DIAPHANA (STOMIIFORMES, STERNOPTYCHIDAE) Ronald C. Baird and George Y. Jumper It has been estimated that more than 80% of the deep sea fish fauna living at depths greater than 1,000 m exhibit sexual dimorphism in the olfactory system (Marshall, 1967). The most common form of dimorphism involves development oflarge, complex olfactory receptors in males while in females the olfactory system is regressed or microsmatic. Marshall also notes that in contrast, mesopelagic fishes living at depths less than 1,000 m generally have well-developed olfactory systems in both sexes and sexual dimorphism is uncommon. Recently, sexual dimorphism was reported in the olfactory organs of two me- sopelagic sternoptychids Argyropelecus hemigymnus and Valenciennellus tri- punctulatus by Baird et aI., 1990. Unlike many of the deeper living fishesdescribed by Marshall (op. cit.) the olfactory systems in females of these species are relatively well developed. The potential advantages of chemical communication to mate location in deep- sea fishes have been explored by Jumper and Baird (1991) and the use of odor cues appears to greatly enhance mate location in A. hemigymnus. The nasal rosettes of the hatchetfish Sternoptyx diaphana do not exhibit di- morphism. More importantly, the nasal rosettes of both sexes in S. diaphana are much smaller in size, and considerably less complex in structure than in A. hemi- gymnus. In this article, we describe the external morphology of the olfactory organs in sexually mature individuals of S. diaphana, compare them to that found in A. -
Biodiversity of Arctic Marine Fishes: Taxonomy and Zoogeography
Mar Biodiv DOI 10.1007/s12526-010-0070-z ARCTIC OCEAN DIVERSITY SYNTHESIS Biodiversity of arctic marine fishes: taxonomy and zoogeography Catherine W. Mecklenburg & Peter Rask Møller & Dirk Steinke Received: 3 June 2010 /Revised: 23 September 2010 /Accepted: 1 November 2010 # Senckenberg, Gesellschaft für Naturforschung and Springer 2010 Abstract Taxonomic and distributional information on each Six families in Cottoidei with 72 species and five in fish species found in arctic marine waters is reviewed, and a Zoarcoidei with 55 species account for more than half list of families and species with commentary on distributional (52.5%) the species. This study produced CO1 sequences for records is presented. The list incorporates results from 106 of the 242 species. Sequence variability in the barcode examination of museum collections of arctic marine fishes region permits discrimination of all species. The average dating back to the 1830s. It also incorporates results from sequence variation within species was 0.3% (range 0–3.5%), DNA barcoding, used to complement morphological charac- while the average genetic distance between congeners was ters in evaluating problematic taxa and to assist in identifica- 4.7% (range 3.7–13.3%). The CO1 sequences support tion of specimens collected in recent expeditions. Barcoding taxonomic separation of some species, such as Osmerus results are depicted in a neighbor-joining tree of 880 CO1 dentex and O. mordax and Liparis bathyarcticus and L. (cytochrome c oxidase 1 gene) sequences distributed among gibbus; and synonymy of others, like Myoxocephalus 165 species from the arctic region and adjacent waters, and verrucosus in M. scorpius and Gymnelus knipowitschi in discussed in the family reviews. -
1University of Rhode Island, 2Museum of Comparative Zoology, Harvard University E-Mail: [email protected]
The Lateral Line System of Deep-Sea Fishes: Preliminary Observations on Stomiiform Fishes Ashley N. Marranzino1 and Jacqueline F. Webb1,2 1University of Rhode Island, 2Museum of Comparative Zoology, Harvard University E-mail: [email protected] Introduction A Stomiid with LL Canals Gonostomatidae: Cyclothone The lateral line (LL) system of so Figure 3: LL canals in Aristostomias. shallow water taxa is well-known, Figure 7: Osteology of A) Aristostomias sp. (from Morrow, but descriptions of the LL systems Cyclothone spp. A-C) 1964, FNWA). B-E are µCT images Cleared and stained C. of deep-sea fishes are scattered A B 100 µm of A. tittmanni (MCZ163949). B) A A acclinidens (with gill arches and incomplete (reviewed in Webb, lateral view indicating supraorbital removed) shows no so 10 mm 2014). The little data that is (so) LL canal confirming the evidence of LL canals in A) B io available provides evidence for two description by Fink (1985). C) Dorsal lateral, B) dorso-lateral or C) morphological strategies: 1) view (same individual as in B shows ventral views. The “double” bilateral supraorbital canal in the md Widened canals with large canal view of the left and right C D 20 µm frontal bone (outlined by dashed neuromasts (Fig. 1A-B; Garman, bones in A are due to the circles). D) Rostral view shows positioning of the specimen. 1899; Jakubowski, 1974; Marshall, Figure 1: Deep-sea species with widened bilateral supraorbital canals in the B C 2 mm D-E) µCT images of C. canals or reduced canals with superficial 2 mm 1996), 2) Reduced canals with frontal bones, with a pore indicated microdon (MCZ89489) in D) superficial neuromasts that in the neuromasts (SN). -
Molecular Phylogeny and the Evolution of an Adaptive Visual System in Deep-Sea Dragonfishes (Stomiiformes: Stomiidae)
ORIGINAL ARTICLE doi:10.1111/evo.12322 THE COMPLEX EVOLUTIONARY HISTORY OF SEEING RED: MOLECULAR PHYLOGENY AND THE EVOLUTION OF AN ADAPTIVE VISUAL SYSTEM IN DEEP-SEA DRAGONFISHES (STOMIIFORMES: STOMIIDAE) Christopher P. Kenaley,1,2 Shannon C. DeVaney,3 and Taylor T. Fjeran4 1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138 2E-mail: [email protected] 3Life Science Department, Los Angeles Pierce College, Woodland Hills, California 91371 4College of Forestry, Oregon State University, Corvallis, Oregon 97331 Received December 12, 2012 Accepted November 12, 2013 The vast majority of deep-sea fishes have retinas composed of only rod cells sensitive to only shortwave blue light, approximately 480–490 nm. A group of deep-sea dragonfishes, the loosejaws (family Stomiidae), possesses far-red emitting photophores and rhodopsins sensitive to long-wave emissions greater than 650 nm. In this study, the rhodopsin diversity within the Stomiidae is surveyed based on an analysis of rod opsin-coding sequences from representatives of 23 of the 28 genera. Using phylogenetic inference, fossil-calibrated estimates of divergence times, and a comparative approach scanning the stomiid phylogeny for shared genotypes and substitution histories, we explore the evolution and timing of spectral tuning in the family. Our results challenge both the monophyly of the family Stomiidae and the loosejaws. Despite paraphyly of the loosejaws, we infer for the first time that far-red visual systems have a single evolutionary origin within the family and that this shift in phenotype occurred at approximately 15.4 Ma. In addition, we found strong evidence that at approximately 11.2 Ma the most recent common ancestor of two dragonfish genera reverted to a primitive shortwave visual system during its evolution from a far-red sensitive dragonfish. -
Examples of the Golden Ratio You Can Find in Nature
Examples Of The Golden Ratio You Can Find In Nature It is often said that math contains the answers to most of universe’s questions. Math manifests itself everywhere. One such example is the Golden Ratio. This famous Fibonacci sequence has fascinated mathematicians, scientist and artists for many hundreds of years. The Golden Ratio manifests itself in many places across the universe, including right here on Earth, it is part of Earth’s nature and it is part of us. In mathematics, the Fibonacci sequence is the ordering of numbers in the following integer sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144… and so on forever. Each number is the sum of the two numbers that precede it. The Fibonacci sequence is seen all around us. Let’s explore how your body and various items, like seashells and flowers, demonstrate the sequence in the real world. As you probably know by now, the Fibonacci sequence shows up in the most unexpected places. Here are some of them: 1. Flower petals number of petals in a flower is often one of the following numbers: 3, 5, 8, 13, 21, 34 or 55. For example, the lily has three petals, buttercups have five of them, the chicory has 21 of them, the daisy has often 34 or 55 petals, etc. 2. Faces Faces, both human and nonhuman, abound with examples of the Golden Ratio. The mouth and nose are each positioned at golden sections of the distance between the eyes and the bottom of the chin.