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Symbiotic relationships between plants and fungi are extremely common in nature, ranging from highly parasitic to closely mutualistic. Grasses, which are common and ecologically important components of many ecosystems worldwide, are often infected by clandestine, endosymbiotic fungi that grow within their stems, leaves, and seeds. This book attempts to synthesize the accumulating literature on grass-endophyte symbioses within a modern ecological and evolutionary framework. Topics covered include effects of endophytes on host growth, physiology, reproduction, and competitive ability in both agronomically important forages such as tall fescue and perennial ryegrass and in native grasses. Also, endophyte-host interactions are explored in relation to abiotic (e.g., drought) and biotic stresses (e.g., herbivory). Possible effects of endophyte infection on community and ecosystem-level processes are discussed. The ecological outcomes and coevolutionary dynamics of grass-endophyte associations are shown to be highly contingent on host and endophyte genotypes as well as environmental conditions. In addition to synthesizing much of the current literature on grass-endophyte interactions in natural and managed habitats, this book highlights gaps in current knowledge of specific aspects of symbiosis ecology and suggests many avenues for future research. Endophytic fungi are common in plants yet the nature of these interactions and how they cascade upward to communities and ecosystems are largely unknown.

This book is a collection of nineteen chapters where summaries of major ecological and evolutionary questions have been asked and responded using dragonflies and damselflies as study subjects. Each chapter is written by a well-respected scientist. The topics covered are: demography, population and community ecology, life-history, distribution, abundance, migration, conservation, applied use, predator-prey interactions, mating isolation, lifetime reproductive success estimates, reproduction vs. survival, parasite-host relationships, cryptic female choice, sexual conflict, territoriality, sex-limited colour polymorphisms, sexual size dimorphism, flight performance, and wing evolution. Each chapter puts forward new data and hypothesis in relation to further ecological and evolutionary questions.

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.

Community ecology is the study of the interactions between populations of coexisting species. This book provides a state of the art in theory, models and applications of community ecology, with special attention to its topology, dynamics, the importance of spatial and temporal scale as well as applications to emerging problems in human-dominated ecosystems (including the restoration and reconstruction of viable communities). It adopts a mainly theoretical approach and focuses on the use of network-based theories and models which are little explored in standard community ecology textbooks. The book includes discussion of the effects of biotic invasions on natural communities, the linking of ecological network structure to empirically measured community approaches, the effects of evolution on community patterns and processes, and the integration of fundamental interactions into ecological networks. A final chapter indicates future research directions for the discipline. As such, this book provides ideal graduate seminar course material. Community Ecology will be suitable for graduate-level students as well as professional researchers in the fields of population and community ecology, network biology and theoretical ecology.

Many infectious diseases of recent concern, including malaria, cholera, plague, and Lyme disease, have emerged from complex ecological communities involving multiple hosts and their associated parasites. Several of these diseases appear to be influenced by human impacts on the environment, for example intensive agriculture, clear-cut forestry, and habitat loss, and fragmentation. Such environmental impacts may affect many species at trophic levels below or above the host community. Thus, the prevalence of both human and wildlife diseases may alter in unanticipated ways as a result of changes in the structure and composition of ecological communities. This book highlights exciting advances in theoretical and empirical research aimed towards a better understanding of the importance of community structure in the emergence of infectious diseases. To date, research on host-parasite systems has tended to explore only a limited set of community interactions, and little effort has been devoted to addressing complications, such as multiple-host-multiple-parasite systems; sequential hosts acting on different trophic levels; alternate hosts with spatially varying interactions; or stochastic effects resulting from small population size in at least one alternate host species. The chapters in this book illustrate aspects of community ecology that influence pathogen transmission rates and disease dynamics in a wide variety of study systems. It communicates a clear message: studies of epidemiology can be approached from the perspective of community ecology, and students of community ecology can contribute significantly to epidemiology.

From scorching, barren deserts to humid tropical forests, from deep in the soil, to high in the tree canopies, ants are everywhere! Comprising a substantial part of living biomass on earth, ants are integral to the functioning of terrestrial ecosystems. More than 12,000 species have been described to date, and it is estimated that perhaps as many still await classification. Their social structure provides a rich ground for exploring how division of labour affects the acquisition of resources, foraging and defensive behaviours, and coevolution with the flora and fauna with which they interact. The study of ants has led to significant advances in our understanding of insect evolution, global diversity patterns, competitive interactions, mutualisms, ecosystem's responses to change, and biological invasions. Ant Ecology explores these and other key ecological issues and new developments in myrmecology across a range of scales. The book begins with a global perspective on species diversity in time and space and explores interactions at the community level before describing the population ecology of these social insects. The final section covers the recent ecological phenomenon of invasive ants: how they move across the globe, invade, affect ecosystems, and are managed by humans. Each chapter links ant ecology to broader ecological principles, provides a succinct summary, and discusses future research directions. The Synthesis and Perspectives highlights contributions of ant ecology to ecology more broadly, and outlines promising areas for future research.

This book focuses on the influence of climate variability on the marine ecosystems of the North Atlantic. The ecological impact of climate variability on population dynamics is addressed at the full range of trophic levels, from phytoplankton through zooplankton and fish to marine birds. Climate effects on biodiversity and community structure are also examined. The book discusses what is currently known about how climate affects the ecological systems of the North Atlantic, and then places these insights within a broader ecological perspective. Many of the general features of the North Atlantic region are also seen in other marine ecosystems as well as terrestrial and freshwater systems. The final section of the book makes these generalities more explicit, so as to stimulate communication and promote co-operation amongst researchers who may previously have worked in semi-isolation. The book comprises five main sections: background (general introduction, atmospheric and ocean climate of the North Atlantic, and modelling methodology), plankton populations (phytoplankton and zooplankton), fish and seabird populations, community ecology (phytoplankton, benthos and fish), and the final section consisting of six commentaries from scientists working in areas outside the North Atlantic marine sector. In order to enhance integration, a series of introductions link chapters and sections. Throughout the book, numerous examples highlight different aspects of ecology-climate interactions. They document recent progress and illustrate the challenges of trying to understand ecological processes and patterns in the light of climate variations.

Phylogenetic trees are hypotheses depicting the degree of relatedness between species and have, therefore, been critical pieces of information for evolutionary biologists in their research programs for decades. Phylogenies in ecology, on the other hand, have traditionally been used infrequently or all out avoided except in those instances where the researcher was forced to use one to account for non-independence in their data. Part of this avoidance was due to a lack of reliable phylogenetic information for the species being investigated. It was also partly due to ecologists having relatively little training in phylogenetics, thereby reducing their ability to make new important connections across disciplines and lines of thought. At least this was the case until approximately 15 years ago when a quick series of conceptual and methodological advances set the stage for a landslide of phylogenetically informed papers in ecology. Despite this large volume of papers regarding phylogenetic ecology, many of the key reasons and goals for integrating phylogenies into ecology have been left by the wayside. Here, I attempt to outline phylogenetic ecology as it stands today and propose a series of modifications to how ecologists use phylogenies with the goal of promoting a more meaningful synthesis of evolutionary biology and ecology via phylogenetic information.

This book is about the identification and interpretation of nature’s large-scale patterns of species co-occurrence and what we can deduce from them about how nature works. We present Diamond’s assembly rules. He suggested that similar species avoid each other, choosing different islands or, on large islands, different elevations within an island, for no better explanation than to avoid each other. Diamond concentrated on birds in two island groups off New Guinea—the Solomons and the Bismarcks. Diamond’s ideaswere vigorously challenged by those who suggested the patterns were simply chance occurrences. In a series of papers, some argued that Diamond’s assembly rules were poorly constructed and that, moreover, his observations did not support them. Certainly, critics made an important contribution to the study of ecological patterns by requiring observed distributions to be compared to carefully constructed null hypotheses. Developing appropriate statistical methods to analyze these patterns in nature is difficult, though it is now a solved problem. We confirm patterns of mutual exclusivity in some island groups, though not all. Finally, we extend these ideas to species along elevational gradients and to applications involving food webs.