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Rarely have humans been as threatened by viruses as they are today. It almost seems as if a virus invasion is taking place. Viruses have lately been coming out of nowhere and appearing in the strangest places — exotic viruses about which no one had ever heard before. Many human viruses have started out in the animal world. Are these viruses maybe escaping from their natural hosts? Are human beings simply available as easy prey? Why is all this happening now, and what does it mean for our future? What can we do to defend ourselves? This book addresses viral adaptation as a general phenomenon and examines the implications for public health of human behavior altering viral ecosystems. This book discusses the phenomenon of viral emergence.

Ecologists, epidemiologists, and evolutionary biologists are increasingly aware of the significance of parasites in the study of ecosystems. This book provides a summary of the issues involved as well as an overview of the possibilities offered by this research topic, using well-documented case-studies to illustrate the main trends and prospects in this area. This is the first book devoted to the comprehension of both the roles and consequences of pathogens in ecosystems.

Standardized approaches for the measurement of primary production — the rate of energy storage in the organic matter of plants — are essential to facilitate scientific comparisons and syntheses as well as policy and management on global climate change and the carbon cycle. This book provides an overview of the principles that should underlie every program of measurement of primary production in the Earth's major biomes. Each of seven biome-based chapters provides an overview of essential features of primary production processes in the biome and detailed descriptions of the procedures used to quantify primary production in grasslands, shrublands, forests, peatlands and tundra, salt marshes, marine pelagic, and freshwater ecosystems. Recent advances in the measurement of belowground production in terrestrial biomes are described. The book also provides detailed guidelines for information management based upon current experiences of the US Long-Term Ecological Research network. Advanced techniques are described for scaling up empirical measurements of primary production using remotely-sensed information. Finally, the principles and practices for quantifying uncertainty in primary production measurements are explored using examples from various biomes.

How we determine what is nature, what is wild, or even what in nature is worth protecting occurs through our human perspective. Whether it is a charismatic manatee or a majestic redwood, we care about and protect the things we love because they offer us something we value. To make this value relevant in the economic marketplace of competing choices, Wild Capital: Nature’s Economic and Ecological Wealth relies on the ecosystem services model, where nature’s value is determined through the services intact ecosystems provide to our well-being. As one of the recreation components of this model, this book uses ecotourism and the changing tourist dynamic, as well as our evolving relationship with nature, to demonstrate how we can assign a measurable worth to natural resources. If a developer or a policy maker can more equitably compare the capital asset value of development with that of wild nature, better decisions regarding economic and ecological trade-offs can be made. Wild Capital then incorporates the cultural bias we have for charismatic megafauna to link policy decisions regarding biodiversity and habitat conservation to those charismatic animals we care about so intensely. The five megafauna case studies provide solid evidence of the role charismatic species can play in protecting our planet’s biodiversity and ensuring our well-being long into the future.

This book provides a comprehensive, up-to-date synthesis of what is known about soil biodiversity and the factors that regulate its distribution, as well as the functional significance of below-ground biodiversity for ecosystem form and function. It describes the vast diversity of biota that live in the soil environment — the most complex habitat on Earth — and discusses the factors that act as determinants of this diversity across different spatial and temporal scales. This book also considers how biotic interactions in soil influence the important soil processes of decomposition and nutrient cycling. It demonstrates how interactions and feedbacks between diverse plant and soil communities act as important drivers of ecosystem form and function. The importance of these relationships for understanding how ecosystems respond to global change phenomena, including climate change, is discussed in depth. Much is still to be learned about the soil biota and their roles in ecosystems, and the author highlights some of the many challenges that face ecologists in the exploration of soil. This book provides an introduction to the biology of soil, and also discusses the most recent developments in this progressive field of ecology. The importance of soil biotic interactions for community and ecosystem ecology is illustrated through the use of numerous examples and case studies.

Viruses are everywhere, infecting all sorts of living organisms, from the tiniest bacteria to the largest mammals. Many are harmful parasites, but viruses also play a major role as drivers of our evolution as a species and are essential regulators of the composition and complexity of ecosystems on a global scale. This book draws on complex systems theory to provide a fresh look at viral origins, populations, and evolution, and the coevolutionary dynamics of viruses and their hosts. New viruses continue to emerge that threaten people, crops, and farm animals. Viruses constantly evade our immune systems, and antiviral therapies and vaccination campaigns can be powerless against them. These unique characteristics of virus biology are a consequence of their tremendous evolutionary potential, which enables viruses to quickly adapt to any environmental challenge. This book presents a unified framework for understanding viruses as complex adaptive systems. It shows how the application of complex systems theory to viral dynamics has provided new insights into the development of AIDS in patients infected with HIV-1, the emergence of new antigenic variants of the influenza A virus, and other cutting-edge advances. The book also extends the analogy of viruses to the evolution of other replicators such as computer viruses, cancer, and languages.

Understanding the mechanisms driving biological diversity remains a central problem in ecology and evolutionary biology. Traditional explanations assume that differences in selection pressures lead to different adaptations in geographically separated locations. This book takes a different approach and explores adaptive diversification—diversification rooted in ecological interactions and frequency-dependent selection. In any ecosystem, birth and death rates of individuals are affected by interactions with other individuals. What is an advantageous phenotype therefore depends on the phenotype of other individuals, and it may often be best to be ecologically different from the majority phenotype. Such rare-type advantage is a hallmark of frequency-dependent selection and opens the scope for processes of diversification that require ecological contact rather than geographical isolation. This book investigates adaptive diversification using the mathematical framework of adaptive dynamics. Evolutionary branching is a paradigmatic feature of adaptive dynamics that serves as a basic metaphor for adaptive diversification, and the book explores the scope of evolutionary branching in many different ecological scenarios, including models of coevolution, cooperation, and cultural evolution. It also uses alternative modeling approaches. Stochastic, individual-based models are particularly useful for studying adaptive speciation in sexual populations, and partial differential equation models confirm the pervasiveness of adaptive diversification. Showing that frequency-dependent interactions are an important driver of biological diversity, the book provides a comprehensive theoretical treatment of adaptive diversification.

Construction behaviour occurs across the entire spectrum of the animal kingdom and affects the survival of both builders and other organisms associated with them. This book provides a comprehensive overview of the biology of animal building. It recognizes three broad categories of built structure: homes, traps, and courtship displays. Even though some of these structures are complex and very large, the behaviour required to build them is generally simple and the anatomy for building unspecialized. Standardization of building materials helps to keep building repertoires simple, while self-organizing effects help create complexity. In a case-study approach to function, insects demonstrate how homes can remain operational while they grow, spiderwebs illustrate mechanical design, and the displays of bowerbirds raise the possibility of persuasion through design rather than just decoration. Studies of the costs to builders provide evidence of optimal designs and of trade-offs with other life history traits. As ecosystem engineers, the influence of builders is extensive and their effect is generally to enhance biodiversity through niche construction. Animal builders can therefore represent model species for the study of the emerging subject of environmental inheritance. Building, and in particular building with silk, has been demonstrated to have important evolutionary consequences.

This textbook provides a unique and thorough look at the application of chemical biomarkers to aquatic ecosystems. Defining a chemical biomarker as a compound that can be linked to particular sources of organic matter identified in the sediment record, the book indicates that the application of these biomarkers for an understanding of aquatic ecosystems consists of a biogeochemical approach that has been quite successful but underused. This book offers a wide-ranging guide to the broad diversity of these chemical biomarkers, is the first to be structured around the compounds themselves, and examines them in a connected and comprehensive way. This book is appropriate for advanced undergraduate and graduate students seeking training in this area; researchers in biochemistry, organic geochemistry, and biogeochemistry; researchers working on aspects of organic cycling in aquatic ecosystems; and paleoceanographers, petroleum geologists, and ecologists.

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, this book synthesizes and reconciles modern and classical perspectives into a general unified theory. The book brings together outcomes from population-, community-, and ecosystem-level approaches under the common currency of energy or material fluxes. It shows that these approaches—often studied in isolation—all have the same general implications in terms of stability of the population dynamics. 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. The book uses this powerful general framework to discuss the effects of human impact on ecological stability and sustainability, and it 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.

Nutrition has long been considered more the domain of medicine and agriculture than of the biological sciences, yet it touches and shapes all aspects of the natural world. The need for nutrients determines whether wild animals thrive, how populations evolve and decline, and how ecological communities are structured. This is the first book to address nutrition's enormously complex role in biology, both at the level of individual organisms and in their broader ecological interactions. The book provides a comprehensive theoretical approach to the analysis of nutrition—the Geometric Framework. The book shows how it can help us to understand the links between nutrition and the biology of individual animals, including the physiological mechanisms that determine the nutritional interactions of the animal with its environment, and the consequences of these interactions in terms of health, immune responses, and lifespan. The book explains how these effects translate into the collective behavior of groups and societies, and in turn influence food webs and the structure of ecosystems. It then demonstrates how the Geometric Framework can be used to tackle issues in applied nutrition, such as the problem of optimizing diets for livestock and endangered species, and how it can also help to address the epidemic of human obesity and metabolic disease.

Rising temperatures are affecting organisms in all of Earth's biomes, but the complexity of ecological responses to climate change has hampered the development of a conceptually unified treatment of them. In a remarkably comprehensive synthesis, this book presents past, ongoing, and future ecological responses to climate change in the context of two simplifying hypotheses, facilitation and interference, arguing that biotic interactions may be the primary driver of ecological responses to climate change across all levels of biological organization. The author's synthesis and analyses of ecological consequences of climate change extend from the Late Pleistocene to the present, and through the next century of projected warming. The book's investigation is grounded in classic themes of enduring interest in ecology, but developed around novel conceptual and mathematical models of observed and predicted dynamics. Using stability theory as a recurring theme, the book argues that the magnitude of climatic variability may be just as important as the magnitude and direction of change in determining whether populations, communities, and species persist. It urges a more refined consideration of species interactions, emphasizing important distinctions between lateral and vertical interactions and their disparate roles in shaping responses of populations, communities, and ecosystems to climate change.

This book provides a synthesis of theoretical and empirical food web research. Whether they are binary systems or weighted networks, food webs are of particular interest to ecologists by providing a macroscopic view of ecosystems. They describe interactions between species and their environment, and subsequent advances in the understanding of their structure, function, and dynamics are of vital importance to ecosystem management and conservation. This book covers issues of structure, function, scaling, complexity, and stability in the contexts of conservation, fisheries, and climate. Although the focus of this volume is upon aquatic food webs (where many of the recent advances have been made), many other issues are addressed.

Global environmental change, which includes climate change, biodiversity loss, changes in hydrological and biogeochemical cycles, and intensive exploitation of natural resources, is having significant impacts on the world's oceans. This book advances knowledge of the structure and functioning of marine ecosystems, and their past, present, and future responses to physical and anthropogenic forcing. The book illustrates how climate and humans impact marine ecosystems by a comprehensive review of the physical and ecological processes that structure marine ecosystems and the observation, experimentation, and modelling approaches required for their study. Recognizing the interactive roles played by humans in using marine resources and in responding to global changes in marine systems, the book includes chapters on the human dimensions of marine ecosystem changes and on effective management approaches in the era of change. Part IV reviews the state of the art in predicting the responses of marine ecosystems to future global change scenarios. The book provides a synthesis of the work conducted under the auspices of the Global Ocean Ecosystems Dynamics (GLOBEC) project over the last two decades, as the largest, multi-disciplinary, international effort focused on understanding the impacts of external forcing on the structure and dynamics of global marine ecosystems.