Food Web Complexity and Community Dy~~Amics Gary A. Polis
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Backyard Food
Suggested Grades: 2nd - 5th BACKYARD FOOD WEB Wildlife Champions at Home Science Experiment 2-LS4-1: Make observations of plants and animals to compare the diversity of life in different habitats. What is a food web? All living things on earth are either producers, consumers or decomposers. Producers are organisms that create their own food through the process of photosynthesis. Photosynthesis is when a living thing uses sunlight, water and nutrients from the soil to create its food. Most plants are producers. Consumers get their energy by eating other living things. Consumers can be either herbivores (eat only plants – like deer), carnivores (eat only meat – like wolves) or omnivores (eat both plants and meat - like humans!) Decomposers are organisms that get their energy by eating dead plants or animals. After a living thing dies, decomposers will break down the body and turn it into nutritious soil for plants to use. Mushrooms, worms and bacteria are all examples of decomposers. A food web is a picture that shows how energy (food) passes through an ecosystem. The easiest way to build a food web is by starting with the producers. Every ecosystem has plants that make their own food through photosynthesis. These plants are eaten by herbivorous consumers. These herbivores are then hunted by carnivorous consumers. Eventually, these carnivores die of illness or old age and become food for decomposers. As decomposers break down the carnivore’s body, they create delicious nutrients in the soil which plants will use to live and grow! When drawing a food web, it is important to show the flow of energy (food) using arrows. -
Body Size and Biomass Distributions of Carrion Visiting Beetles: Do Cities Host Smaller Species?
Ecol Res (2008) 23: 241–248 DOI 10.1007/s11284-007-0369-9 ORIGINAL ARTICLE Werner Ulrich Æ Karol Komosin´ski Æ Marcin Zalewski Body size and biomass distributions of carrion visiting beetles: do cities host smaller species? Received: 15 November 2006 / Accepted: 14 February 2007 / Published online: 28 March 2007 Ó The Ecological Society of Japan 2007 Abstract The question how animal body size changes Introduction along urban–rural gradients has received much attention from carabidologists, who noticed that cities harbour Animal and plant body size is correlated with many smaller species than natural sites. For Carabidae this aspects of life history traits and species interactions pattern is frequently connected with increasing distur- (dispersal, reproduction, energy intake, competition; bance regimes towards cities, which favour smaller Brown et al. 2004; Brose et al. 2006). Therefore, species winged species of higher dispersal ability. However, body size distributions (here understood as the fre- whether changes in body size distributions can be gen- quency distribution of log body size classes, SSDs) are eralised and whether common patterns exist are largely often used to infer patterns of species assembly and unknown. Here we report on body size distributions of energy use (Peters 1983; Calder 1984; Holling 1992; carcass-visiting beetles along an urban–rural gradient in Gotelli and Graves 1996; Etienne and Olff 2004; Ulrich northern Poland. Based on samplings of 58 necrophages 2005a, 2006). and 43 predatory beetle species, mainly of the families Many of the studies on local SSDs focused on the Catopidae, Silphidae, and Staphylinidae, we found number of modes and the shape. -
06-Secondary Productivity.Pptx
BIO 3072 !Ecology !Eric L. Peters! Ecological (Biomass) Production! Earth Area Available to Support Humans! Primary Production:! Productive sea and land area Production of autotroph (producer)" biomass! available to support each Autotrophs capture and store their own" energy and synthesize their own" person in Africa: ! structural materials! 1.36 ha! Limited by photosynthetic rates! …on Earth: 1.90 ha! Secondary Production:! Production of heterotroph" Used by each W. European/U.S. (consumer) biomass! citizen:" Heterotrophs’ structural" 5.06/5.26 ha! materials (and energy) must be" World obtained from their food! Productive sea and land area needed to produce Wildlife Limited by primary productivity, number and efficiency of energy the products consumed by each U.S. citizen:" Fund," transfers, and other factors. Many chemical elements (e.g., Ca and P) 9.71 ha (the CSU campus is 64.75 ha: enough to Living Planet must be provided in specific chemical forms or combinations! sustain 12.3 U.S. citizens) ! Report 2002. ! Nutrient Requirements of Consumers! Energy-bearing Nutrients and Respiration! !Edible, adj. good to eat and wholesome to digest, as a worm Cells use many organic molecules as fuel for respiration:! to a toad, a toad to a snake, a snake to a pig, a pig to a man, and a man to a worm.! –Ambrose Bierce, The Devil’s Dictionary !" ! There is tremendous variability in organismal nutritional requirements, as well as in the adaptations to meet those needs, e.g.,! Insects require a dietary source of cholesterol, mammals manufacture -
Modeling Techniques
Appendix A Modeling Techniques A.1 Population Growth Models Using Differential Equations Our main goal here is to introduce a few modeling techniques we use throughout this book. We do not intend however to provide here the fundamentals on modeling, a tutorial or a review. For these, we refer to other sources (DeAngelis et al. 1992; Ford 2009; Grimm et al. 2006; Kuang 1993). This Appendix is rather a refresher as well as an example of why using different modeling techniques for one and the same problem can be beneficial to understand biological processes better. We start with the simple exponential population growth to make modeling accessible even to complete beginners. Biologists generally define a population as a collection of individuals that belong to the same species and can potentially breed with each other. One of the best-known early models on population growth was outlined by Malthus (1798). He famously maintained that the human population is predicted to grow in an exponential manner, but the crucial products needed to sustain the population grow in but a linear manner. He argued that these different types of growths will trigger disasters when the population’s needs are not satisfied. The basic exponential growth model consists of a single positive feedback loop that arises from the fact that every individual (N) is predicted to have a fixed number of offspring (r), regardless of the size of the population, and thus also regardless of the remaining resources in the habitat: dN = rN dt (A.1.1) This exponential growth model had a profound effect on biology such as developing the theory of natural selection (Darwin 1859). -
Fisheries in Large Marine Ecosystems: Descriptions and Diagnoses
Fisheries in Large Marine Ecosystems: Descriptions and Diagnoses D. Pauly, J. Alder, S. Booth, W.W.L. Cheung, V. Christensen, C. Close, U.R. Sumaila, W. Swartz, A. Tavakolie, R. Watson, L. Wood and D. Zeller Abstract We present a rationale for the description and diagnosis of fisheries at the level of Large Marine Ecosystems (LMEs), which is relatively new, and encompasses a series of concepts and indicators different from those typically used to describe fisheries at the stock level. We then document how catch data, which are usually available on a smaller scale, are mapped by the Sea Around Us Project (see www.seaaroundus.org) on a worldwide grid of half-degree lat.-long. cells. The time series of catches thus obtained for over 180,000 half-degree cells can be regrouped on any larger scale, here that of LMEs. This yields catch time series by species (groups) and LME, which began in 1950 when the FAO started collecting global fisheries statistics, and ends in 2004 with the last update of these datasets. The catch data by species, multiplied by ex-vessel price data and then summed, yield the value of the fishery for each LME, here presented as time series by higher (i.e., commercial) groups. Also, these catch data can be used to evaluate the primary production required (PPR) to sustain fisheries catches. PPR, when related to observed primary production, provides another index for assessing the impact of the countries fishing in LMEs. The mean trophic level of species caught by fisheries (or ‘Marine Trophic Index’) is also used, in conjunction with a related indicator, the Fishing-in-Balance Index (FiB), to assess changes in the species composition of the fisheries in LMEs. -
Density Dependence in Demography and Dispersal Generates Fluctuating
Density dependence in demography and dispersal generates fluctuating invasion speeds Lauren L. Sullivana,1, Bingtuan Lib, Tom E. X. Millerc, Michael G. Neubertd, and Allison K. Shawa aDepartment of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN 55108; bDepartment of Mathematics, University of Louisville, Louisville, KY 40292; cDepartment of BioSciences, Program in Ecology and Evolutionary Biology, Rice University, Houston, TX 77005; and dBiology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 Edited by Alan Hastings, University of California, Davis, CA, and approved March 30, 2017 (received for review November 23, 2016) Density dependence plays an important role in population regu- is driven by reproduction and dispersal from high-density pop- lation and is known to generate temporal fluctuations in popu- ulations behind the invasion front (13–15)]. The conventional lation density. However, the ways in which density dependence wisdom of a long-term constant invasion speed is widely applied affects spatial population processes, such as species invasions, (16, 17). are less understood. Although classical ecological theory suggests In contrast to classic approaches that emphasize a long-term that invasions should advance at a constant speed, empirical work constant speed, there is growing empirical recognition that inva- is illuminating the highly variable nature of biological invasions, sion dynamics can be highly variable and idiosyncratic (18–25). which often exhibit nonconstant spreading speeds, even in sim- There are several theoretical explanations for fluctuations in ple, controlled settings. Here, we explore endogenous density invasion speed (which we define here as any persistent tem- dependence as a mechanism for inducing variability in biologi- poral variability in spreading speed), including stochasticity in cal invasions with a set of population models that incorporate either demography or dispersal (24–28) and temporal or spatial density dependence in demographic and dispersal parameters. -
The Evolution and Genomic Basis of Beetle Diversity
The evolution and genomic basis of beetle diversity Duane D. McKennaa,b,1,2, Seunggwan Shina,b,2, Dirk Ahrensc, Michael Balked, Cristian Beza-Bezaa,b, Dave J. Clarkea,b, Alexander Donathe, Hermes E. Escalonae,f,g, Frank Friedrichh, Harald Letschi, Shanlin Liuj, David Maddisonk, Christoph Mayere, Bernhard Misofe, Peyton J. Murina, Oliver Niehuisg, Ralph S. Petersc, Lars Podsiadlowskie, l m l,n o f l Hans Pohl , Erin D. Scully , Evgeny V. Yan , Xin Zhou , Adam Slipinski , and Rolf G. Beutel aDepartment of Biological Sciences, University of Memphis, Memphis, TN 38152; bCenter for Biodiversity Research, University of Memphis, Memphis, TN 38152; cCenter for Taxonomy and Evolutionary Research, Arthropoda Department, Zoologisches Forschungsmuseum Alexander Koenig, 53113 Bonn, Germany; dBavarian State Collection of Zoology, Bavarian Natural History Collections, 81247 Munich, Germany; eCenter for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, 53113 Bonn, Germany; fAustralian National Insect Collection, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT 2601, Australia; gDepartment of Evolutionary Biology and Ecology, Institute for Biology I (Zoology), University of Freiburg, 79104 Freiburg, Germany; hInstitute of Zoology, University of Hamburg, D-20146 Hamburg, Germany; iDepartment of Botany and Biodiversity Research, University of Wien, Wien 1030, Austria; jChina National GeneBank, BGI-Shenzhen, 518083 Guangdong, People’s Republic of China; kDepartment of Integrative Biology, Oregon State -
Plant Diversity Increases with the Strength of Negative Density Dependence at the Global Scale
RESEARCH FOREST ECOLOGY predators, pathogens, or herbivores) and/or com- petition for space and resources (2–4, 7). Numer- ous studies have documented the existence of CNDD in one or several plant species (8–12), and Plant diversity increases with the most of these studies explicitly or implicitly as- sume that stronger CNDD maintains higher spe- strength of negative density cies diversity in communities. However, only a handful of studies have explicitly examined dependence at the global scale the link between CNDD and species diversity (4, 11, 13, 14),andnostudyhasexaminedthis relationship across temperate and tropical lat- Joseph A. LaManna,1,2* Scott A. Mangan,2 Alfonso Alonso,3 Norman A. Bourg,4,5 itudes. Despite decades of study, our understand- Warren Y. Brockelman,6,7 Sarayudh Bunyavejchewin,8 Li-Wan Chang,9 ing of how processes at local scales—such as Jyh-Min Chiang,10 George B. Chuyong,11 Keith Clay,12 Richard Condit,13 density-dependent biotic interactions—influence Susan Cordell,14 Stuart J. Davies,15,16 Tucker J. Furniss,17 Christian P. Giardina,14 18 18 19,20 global patterns of biodiversity remains in flux I. A. U. Nimal Gunatilleke, C. V. Savitri Gunatilleke, Fangliang He, 1 15 21 22 23 ( , ). Robert W. Howe, Stephen P. Hubbell, Chang-Fu Hsieh, Both species-specific and more generalized 14 24 25 15,16 Faith M. Inman-Narahari, David Janík, Daniel J. Johnson, David Kenfack, mechanisms can cause CNDD, but only CNDD 3 24 26 17 Lisa Korte, Kamil Král, Andrew J. Larson, James A. Lutz, caused by species-specific mechanisms can main- 27,28 4 29 Sean M. -
"Density Dependence and Independence"
Density Dependence and Advanced article Independence Article Contents . Introduction: Concepts and Importance in Ecology Mark A Hixon, Oregon State University, Corvallis, Oregon, USA . Mechanisms of Density Dependence . Old Debates Resolved Darren W Johnson, Oregon State University, Corvallis, Oregon, USA . Detecting Density Dependence . Future Directions Online posting date: 15th December 2009 Density dependence occurs when the population growth parameter of interest involves population dynamics, rate, or constituent gain rates (e.g. birth and immi- including the population growth rate and the four primary gration) or loss rates (death and emigration), vary caus- demographic (or vital) rates – birth, death, immigration ally with population size or density (N). When these and emigration – although related parameters, such as growth and fecundity, are also investigated. See also: parameters do not vary with N, they are density-inde- Population Dynamics: Introduction pendent. Direct density dependence, where the popu- Use of the words ‘density dependence’ alone normally lation growth rate or gain rates vary as a negative means ‘direct density dependence’ (or compensation): the function of N, or the loss rates vary as a positive function of per capita (proportional) gain rate (population or indi- N, is necessary but not always sufficient for population vidual growth, fecundity, birth or immigration) decreases regulation. The opposite patterns, inverse density as N increases (Figure 1a) or the loss rate (death and/or dependence or the Allee effect, may push endangered emigration) increases as N increases (Figure 1b). The populations towards extinction. Direct density depend- opposite patterns are called inverse density dependence (or ence is caused by competition, and at times, predation. -
Vertical and Horizontal Trophic Networks in the Aroid-Infesting Insect Community of Los Tuxtlas Biosphere Reserve, Mexico
insects Article Vertical and Horizontal Trophic Networks in the Aroid-Infesting Insect Community of Los Tuxtlas Biosphere Reserve, Mexico Guadalupe Amancio 1 , Armando Aguirre-Jaimes 1, Vicente Hernández-Ortiz 1,* , Roger Guevara 2 and Mauricio Quesada 3,4 1 Red de Interacciones Multitróficas, Instituto de Ecología A.C., Xalapa, Veracruz 91073, Mexico 2 Red de Biologia Evolutiva, Instituto de Ecología A.C., Xalapa, Veracruz 91073, Mexico 3 Laboratorio Nacional de Análisis y Síntesis Ecológica, Escuela Nacional de Estudios Superiores Unidad Morelia, Universidad Nacional Autónoma de México, Morelia 58190 Michoacán, Mexico 4 Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia 58190 Michoacán, Mexico * Correspondence: [email protected] Received: 20 June 2019; Accepted: 9 August 2019; Published: 15 August 2019 Abstract: Insect-aroid interaction studies have focused largely on pollination systems; however, few report trophic interactions with other herbivores. This study features the endophagous insect community in reproductive aroid structures of a tropical rainforest of Mexico, and the shifting that occurs along an altitudinal gradient and among different hosts. In three sites of the Los Tuxtlas Biosphere Reserve in Mexico, we surveyed eight aroid species over a yearly cycle. The insects found were reared in the laboratory, quantified and identified. Data were analyzed through species interaction networks. We recorded 34 endophagous species from 21 families belonging to four insect orders. The community was highly specialized at both network and species levels. Along the altitudinal gradient, there was a reduction in richness and a high turnover of species, while the assemblage among hosts was also highly specific, with different dominant species. -
Plants Are Producers! Draw the Different Producers Below
Name: ______________________________ The Unique Producer Every food chain begins with a producer. Plants are producers. They make their own food, which creates energy for them to grow, reproduce and survive. Being able to make their own food makes them unique; they are the only living things on Earth that can make their own source of food energy. Of course, they require sun, water and air to thrive. Given these three essential ingredients, you will have a healthy plant to begin the food chain. All plants are producers! Draw the different producers below. Apple Tree Rose Bushes Watermelon Grasses Plant Blueberry Flower Fern Daisy Bush List the three essential needs that every producer must have in order to live. © 2009 by Heather Motley Name: ______________________________ Producers can make their own food and energy, but consumers are different. Living things that have to hunt, gather and eat their food are called consumers. Consumers have to eat to gain energy or they will die. There are four types of consumers: omnivores, carnivores, herbivores and decomposers. Herbivores are living things that only eat plants to get the food and energy they need. Animals like whales, elephants, cows, pigs, rabbits, and horses are herbivores. Carnivores are living things that only eat meat. Animals like owls, tigers, sharks and cougars are carnivores. You would not catch a plant in these animals’ mouths. Then, we have the omnivores. Omnivores will eat both plants and animals to get energy. Whichever food source is abundant or available is what they will eat. Animals like the brown bear, dogs, turtles, raccoons and even some people are omnivores. -
The Soil Food Web
THE SOIL FOOD WEB HEALTHY SOIL HEALTHY ENVIRONMENT The Soil Food Web Alan Sundermeier Extension Educator and Program Leader, Wood County Extension, The Ohio State University. Vinayak Shedekar Postdoctural Researcher, The Ohio State University. A healthy soil depends on the interaction of many organisms that make up the soil food web. These organisms live all or part of their life cycle in the soil and are respon- sible for converting energy as one organism consumes another. Source: Soil Biology Primer The phospholipid fatty acid (PLFA) test can be used to measure the activity of the soil food web. The following chart shows that mi-crobial activity peaks in early summer when soil is warm and moisture is adequate. Soil sampling for detecting soil microbes should follow this timetable to better capture soil microbe activity. The soil food web begins with the ener- gy from the sun, which triggers photo- synthesis in plants. Photosynthesis re- sults in plants using the sun’s energy to fix carbon dioxide from the atmosphere. This process creates the carbon and organic compounds contained in plant material. This is the first trophic level. Then begins building of soil organic matter, which contains both long-last- ing humus, and active organic matter. Active organic matter contains readily available energy, which can be used by simple soil organisms in the second trophic level of the soil food web. Source: Soil Biology Primer SOILHEALTH.OSU.EDU THE SOIL FOOD WEB - PAGE 2 The second trophic level contains simple soil organisms, which Agriculture can enhance the soil food web to create more decompose plant material.