For over sixty years, understanding the causes of multiannual cycles in animal populations has been a central issue in ecology. This book brings together ten of the leaders in this field to examine the major hypotheses and recent evidence in the field, and to establish that trophic interactions are an important factor in driving at least some of the major regular oscillations in animal populations that have long puzzled ecologists.
How did rodent outbreaks in Germany help to end World War I? What caused the destructive outbreak of rodents in Oregon and California in the late 1950s, the large population outbreak of lemmings in Scandinavia in 2010, and the great abundance of field mice in Scotland in the spring of 2011? Population fluctuations, or outbreaks, of rodents constitute one of the classic problems of animal ecology, and in Population Fluctuations in Rodents, Charles J. Krebs sifts through the last eighty years of research to draw out exactly what we know about rodent outbreaks and what should be the agenda for future research. Krebs has synthesized the research in this area, focusing mainly on the voles and lemmings of the Northern Hemisphere—his primary area of expertise—but also referring to the literature on rats and mice. He covers the patterns of changes in reproduction and mortality and the mechanisms that cause these changes—including predation, disease, food shortage, and social behavior—and discusses how landscapes can affect population changes, methodically presenting the hypotheses related to each topic before determining whether or not the data supports them. He ends on an expansive note, by turning his gaze outward and discussing how the research on rodent populations can apply to other terrestrial mammals. Geared toward advanced undergraduate students, graduate students, and practicing ecologists interested in rodent population studies, this book will also appeal to researchers seeking to manage rodent populations and to understand outbreaks in both natural and urban settings—or, conversely, to protect endangered species.
Why do organisms become extremely abundant one year and then seem to disappear a few years later? Why do population outbreaks in particular species happen more or less regularly in certain locations, but only irregularly (or never at all) in other locations? Complex population dynamics have fascinated biologists for decades. By bringing together mathematical models, statistical analyses, and field experiments, this book offers a comprehensive new synthesis of the theory of population oscillations. Peter Turchin first reviews the conceptual tools that ecologists use to investigate population oscillations, introducing population modeling and the statistical analysis of time series data. He then provides an in-depth discussion of several case studies--including the larch budmoth, southern pine beetle, red grouse, voles and lemmings, snowshoe hare, and ungulates--to develop a new analysis of the mechanisms that drive population oscillations in nature. Through such work, the author argues, ecologists can develop general laws of population dynamics that will help turn ecology into a truly quantitative and predictive science. Complex Population Dynamics integrates theoretical and empirical studies into a major new synthesis of current knowledge about population dynamics. It is also a pioneering work that sets the course for ecology's future as a predictive science.
"Secular Cycles elaborates and expands upon the demographic-structural theory first advanced by Jack Goldstone, which provides an explanation of long-term oscillations. This book tests that theory's specific and quantitative predictions by tracing the dynamics of population numbers, prices and real wages, elite numbers and incomes, state finances, and sociopolitical instability. Turchin and Nefedov study societies in England, France, and Russia during the medieval and early modern periods, and look back at the Roman Republic and Empire. Incorporating theoretical and quantitative history, the authors examine a specific model of historical change and, more generally, investigate the utility of the dynamical systems approach in historical applications."--BOOK JACKET.
The dipteran family Chironomidae is the most widely distributed and frequently the most abundant group of insects in freshwater, with rep resentatives in both terrestrial and marine environments. A very wide range of gradients of temperature, pH, oxygen concentration, salinity, current velocity, depth, productivity, altitude and latitude have been exploited, by at least some chironomid species, and in grossly polluted environments chironomids may be the only insects present. The ability to exist in such a wide range of conditions has been achieved largely by behavioural and physiological adaptations with relatively slight morphological changes. It has been estimated that the number of species world-wide may be as high as 15000. This high species diversity has been attributed to the antiquity of the family, relatively low vagility leading to isolation, and evolutionary plasticity. In many aquatic ecosystems the number of chironomid species present may account for at least 50% of the total macroinvertebrate species recorded. This species richness, wide distribution and tolerance to adverse conditions has meant that the group is frequently recorded in ecological studies but taxonomic difficulties have in the past prevented non-specialist identification beyond family or subfamily level. Recent works, including genetic studies, have meant that the family is receiving much more attention globally.
Black & white print. Concepts of Biology is designed for the typical introductory biology course for nonmajors, covering standard scope and sequence requirements. The text includes interesting applications and conveys the major themes of biology, with content that is meaningful and easy to understand. The book is designed to demonstrate biology concepts and to promote scientific literacy.
Most organisms live in a seasonal environment. During their life cycles, some species face seasons of cold and heat, aridity and abundant rainfall, migration and stable residence, breeding and nonbreeding. Populations grow and decline as supplies of materials essential to their survival wax and wane. Such qualitative truths as these flow obviously from field observations. In this original monograph, Stephen Fretwell analyzes the highly complex interaction between a population and a regularly varying environment in an attempt to define and measure seasonality as a critical parameter in the general theory of population regulation. Concerned primarily with the size and the habitat distribution of populations, Professor Fretwell develops simple models that, when applied to specific populations, usually of birds, demonstrate the effect of seasonal variations on the regulation of populations. He maintains that seasonality, as a concept, is essential to a full understanding of environmental interaction. During the course of his exposition, the author offers several new hypotheses, including theories affecting the breeding, numbers, distribution, and diversity of wintering birds, and a theory affecting the body size of sparrows.
