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Food Webs and Niche Space - Joel E. Cohen - Bog - Princeton University Press - Plusbog.dk

Food Webs and Niche Space - Joel E. Cohen - Bog - Princeton University Press - Plusbog.dk

What is the minimum dimension of a niche space necessary to represent the overlaps among observed niches? This book presents a new technique for obtaining a partial answer to this elementary question about niche space. The author bases his technique on a relation between the combinatorial structure of food webs and the mathematical theory of interval graphs. Professor Cohen collects more than thirty food webs from the ecological literature and analyzes their statistical and combinatorial properties in detail. As a result, he is able to generalize: within habitats of a certain limited physical and temporal heterogeneity, the overlaps among niches, along their trophic (feeding) dimensions, can be represented in a one-dimensional niche space far more often than would be expected by chance alone and perhaps always. This compatibility has not previously been noticed. It indicates that real food webs fall in a small subset of the mathematically possible food webs. Professor Cohen discusses other apparently new features of real food webs, including the constant ratio of the number of kinds of prey to the number of kinds of predators in food webs that describe a community. In conclusion he discusses possible extensions and limitations of his results and suggests directions for future research.

DKK 493.00
1

Food Webs - Kevin S. Mccann - Bog - Princeton University Press - Plusbog.dk

Food Webs - Kevin S. Mccann - Bog - Princeton University Press - Plusbog.dk

Human impacts are dramatically altering our natural ecosystems but the exact repercussions on ecological sustainability and function remain unclear. As a result, food web theory has experienced a proliferation of research seeking to address these critical areas. Arguing that the various recent and classical food web theories can be looked at collectively and in a highly consistent and testable way, Food Webs synthesizes and reconciles modern and classical perspectives into a general unified theory. Kevin McCann brings together outcomes from population-, community-, and ecosystem-level approaches under the common currency of energy or material fluxes. He shows that these approaches--often studied in isolation--all have the same general implications in terms of population dynamic stability. Specifically, increased fluxes of energy or material tend to destabilize populations, communities, and whole ecosystems. With this understanding, stabilizing structures at different levels of the ecological hierarchy can be identified and any population-, community-, or ecosystem-level structures that mute energy or material flow also stabilize systems dynamics. McCann uses this powerful general framework to discuss the effects of human impact on the stability and sustainability of ecological systems, and he demonstrates that there is clear empirical evidence that the structures supporting ecological systems have been dangerously eroded. Uniting the latest research on food webs with classical theories, this book will be a standard source in the understanding of natural food web functions.

DKK 493.00
1

Coexistence in Ecology - Mark A. Mcpeek - Bog - Princeton University Press - Plusbog.dk

Coexistence in Ecology - Mark A. Mcpeek - Bog - Princeton University Press - Plusbog.dk

A comprehensive framework for understanding species coexistenceCoexistence is the central concept in community ecology, but an understanding of this concept requires that we study the actual mechanisms of species interactions. Coexistence in Ecology examines the major features of these mechanisms for species that coexist at different positions in complex food webs, and derives empirical tests from model predictions. Exploring the various challenges species face, Mark McPeek systematically builds a model food web, beginning with an ecosystem devoid of life and then adding one species at a time. With the introduction of each new species, he evaluates the properties it must possess to invade a community and quantifies the changes in the abundances of other species that result from a successful invasion. McPeek continues this process until he achieves a multitrophic level food web with many species coexisting at each trophic level, from omnivores, mutualists, and pathogens to herbivores, carnivores, and basic plants. He then describes the observational and experimental empirical studies that can test the theoretical predictions resulting from the model analyses. Synthesizing decades of theoretical research in community ecology, Coexistence in Ecology offers new perspectives on how to develop an empirical program of study rooted in the natural histories of species and the mechanisms by which they actually interact with one another.

DKK 389.00
1

Coexistence in Ecology - Mark A. Mcpeek - Bog - Princeton University Press - Plusbog.dk

Coexistence in Ecology - Mark A. Mcpeek - Bog - Princeton University Press - Plusbog.dk

A comprehensive framework for understanding species coexistenceCoexistence is the central concept in community ecology, but an understanding of this concept requires that we study the actual mechanisms of species interactions. Coexistence in Ecology examines the major features of these mechanisms for species that coexist at different positions in complex food webs, and derives empirical tests from model predictions. Exploring the various challenges species face, Mark McPeek systematically builds a model food web, beginning with an ecosystem devoid of life and then adding one species at a time. With the introduction of each new species, he evaluates the properties it must possess to invade a community and quantifies the changes in the abundances of other species that result from a successful invasion. McPeek continues this process until he achieves a multitrophic level food web with many species coexisting at each trophic level, from omnivores, mutualists, and pathogens to herbivores, carnivores, and basic plants. He then describes the observational and experimental empirical studies that can test the theoretical predictions resulting from the model analyses. Synthesizing decades of theoretical research in community ecology, Coexistence in Ecology offers new perspectives on how to develop an empirical program of study rooted in the natural histories of species and the mechanisms by which they actually interact with one another.

DKK 894.00
1

Statistics in Theory and Practice - Robert Lupton - Bog - Princeton University Press - Plusbog.dk

Statistics in Theory and Practice - Robert Lupton - Bog - Princeton University Press - Plusbog.dk

Aimed at a diverse scientific audience, including physicists, astronomers, chemists, geologists, and economists, this book explains the theory underlying the classical statistical methods. Its level is between introductory "how to" texts and intimidating mathematical monographs. A reader without previous exposure to statistics will finish the book with a sound working knowledge of statistical methods, while a reader already familiar with the standard tests will come away with an understanding of their strengths, weaknesses, and domains of applicability. The mathematical level is that of an advanced undergraduate; for example, matrices and Fourier analysis are used where appropriate. Among the topics covered are common probability distributions; sampling and the distribution of sampling statistics; confidence intervals, hypothesis testing, and the theory of tests; estimation (including maximum likelihood); goodness of fit (including c2 and Kolmogorov-Smirnov tests); and non-parametric and rank tests. There are nearly one hundred problems (with answers) designed to bring out points in the text and to cover topics slightly outside the main line of development.

DKK 885.00
1

Population and Community Ecology of Ontogenetic Development - Andre M. De Roos - Bog - Princeton University Press - Plusbog.dk

Population and Community Ecology of Ontogenetic Development - Andre M. De Roos - Bog - Princeton University Press - Plusbog.dk

Most organisms show substantial changes in size or morphology after they become independent of their parents and have to find their own food. Furthermore, the rate at which these changes occur generally depends on the amount of food they ingest. In this book, André de Roos and Lennart Persson advance a synthetic and individual-based theory of the effects of this plastic ontogenetic development on the dynamics of populations and communities. De Roos and Persson show how the effects of ontogenetic development on ecological dynamics critically depend on the efficiency with which differently sized individuals convert food into new biomass. Differences in this efficiency--or ontogenetic asymmetry--lead to bottlenecks in and thus population regulation by either maturation or reproduction. De Roos and Persson investigate the community consequences of these bottlenecks for trophic configurations that vary in the number and type of interacting species and in the degree of ontogenetic niche shifts exhibited by their individuals. They also demonstrate how insights into the effects of maturation and reproduction limitation on community equilibrium carry over to the dynamics of size-structured populations and give rise to different types of cohort-driven cycles. Featuring numerous examples and tests of modeling predictions, this book provides a pioneering and extensive theoretical and empirical treatment of the ecology of ontogenetic growth and development in organisms, emphasizing the importance of an individual-based perspective for understanding population and community dynamics.

DKK 653.00
1

Food and Drug Legislation in the New Deal - Charles O. Jackson - Bog - Princeton University Press - Plusbog.dk

Food and Drug Legislation in the New Deal - Charles O. Jackson - Bog - Princeton University Press - Plusbog.dk

In June 1938, Franklin D. Roosevelt signed into law a new Food, Drug, and Cosmetic Act, the first major legislation regulating these industries since the 1906 Wiley law. Eliminating many serious and long-standing abuses in production, labeling, and advertising, the 1938 Act was, in the words of David L. Cowen, "a milestone in federal interest in consumer protection." Despite its importance to the American public, however, its passage was effected only after a long, complex battle between conflicting interest groups.This volume is a study in depth of that five-year struggle, fully documented by records, correspondence, and publications, as well as a social history of the period. The author analyzes the inadequacy of the 1906 law, the roles of Franklin Roosevelt, Henry Wallace, and Rexford Tugwell, the American Medical Association, drug associations, and consumers'' and women''s groups.Originally published in 1970.The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.

DKK 930.00
1

Food and Drug Legislation in the New Deal - Charles O. Jackson - Bog - Princeton University Press - Plusbog.dk

Food and Drug Legislation in the New Deal - Charles O. Jackson - Bog - Princeton University Press - Plusbog.dk

In June 1938, Franklin D. Roosevelt signed into law a new Food, Drug, and Cosmetic Act, the first major legislation regulating these industries since the 1906 Wiley law. Eliminating many serious and long-standing abuses in production, labeling, and advertising, the 1938 Act was, in the words of David L. Cowen, "a milestone in federal interest in consumer protection." Despite its importance to the American public, however, its passage was effected only after a long, complex battle between conflicting interest groups.This volume is a study in depth of that five-year struggle, fully documented by records, correspondence, and publications, as well as a social history of the period. The author analyzes the inadequacy of the 1906 law, the roles of Franklin Roosevelt, Henry Wallace, and Rexford Tugwell, the American Medical Association, drug associations, and consumers'' and women''s groups.Originally published in 1970.The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.

DKK 404.00
1

Getting Something to Eat in Jackson - Joseph C. Ewoodzie - Bog - Princeton University Press - Plusbog.dk

Getting Something to Eat in Jackson - Joseph C. Ewoodzie - Bog - Princeton University Press - Plusbog.dk

James Beard Foundation Book Award Nominee • Winner of the Ida B. Wells-Barnett Book Award, Association of Black Sociologists • Winner of the C. Wright Mills Award, the Society for the Study of Social ProblemsA vivid portrait of African American life in today’s urban South that uses food to explore the complex interactions of race and classGetting Something to Eat in Jackson uses food—what people eat and how—to explore the interaction of race and class in the lives of African Americans in the contemporary urban South. Joseph Ewoodzie Jr. examines how “foodways”—food availability, choice, and consumption—vary greatly between classes of African Americans in Jackson, Mississippi, and how this reflects and shapes their very different experiences of a shared racial identity. Ewoodzie spent more than a year following a group of socioeconomically diverse African Americans—from upper-middle-class patrons of the city’s fine-dining restaurants to men experiencing homelessness who must organize their days around the schedules of soup kitchens. Ewoodzie goes food shopping, cooks, and eats with a young mother living in poverty and a grandmother working two jobs. He works in a Black-owned BBQ restaurant, and he meets a man who decides to become a vegan for health reasons but who must drive across town to get tofu and quinoa. Ewoodzie also learns about how soul food is changing and why it is no longer a staple survival food. Throughout, he shows how food choices influence, and are influenced by, the racial and class identities of Black Jacksonians. By tracing these contemporary African American foodways, Getting Something to Eat in Jackson offers new insights into the lives of Black Southerners and helps challenge the persistent homogenization of blackness in American life.

DKK 228.00
1

Getting Something to Eat in Jackson - Joseph C. Ewoodzie - Bog - Princeton University Press - Plusbog.dk

Getting Something to Eat in Jackson - Joseph C. Ewoodzie - Bog - Princeton University Press - Plusbog.dk

James Beard Foundation Book Award Nominee • Winner of the Ida B. Wells-Barnett Book Award, Association of Black Sociologists • Winner of the C. Wright Mills Award, the Society for the Study of Social ProblemsA vivid portrait of African American life in today’s urban South that uses food to explore the complex interactions of race and classGetting Something to Eat in Jackson uses food—what people eat and how—to explore the interaction of race and class in the lives of African Americans in the contemporary urban South. Joseph Ewoodzie Jr. examines how “foodways”—food availability, choice, and consumption—vary greatly between classes of African Americans in Jackson, Mississippi, and how this reflects and shapes their very different experiences of a shared racial identity. Ewoodzie spent more than a year following a group of socioeconomically diverse African Americans—from upper-middle-class patrons of the city’s fine-dining restaurants to men experiencing homelessness who must organize their days around the schedules of soup kitchens. Ewoodzie goes food shopping, cooks, and eats with a young mother living in poverty and a grandmother working two jobs. He works in a Black-owned BBQ restaurant, and he meets a man who decides to become a vegan for health reasons but who must drive across town to get tofu and quinoa. Ewoodzie also learns about how soul food is changing and why it is no longer a staple survival food. Throughout, he shows how food choices influence, and are influenced by, the racial and class identities of Black Jacksonians. By tracing these contemporary African American foodways, Getting Something to Eat in Jackson offers new insights into the lives of Black Southerners and helps challenge the persistent homogenization of blackness in American life.

DKK 188.00
1