Provides a current, critical review of the importance of interspecific competition, considering the evolutionary effects of interspecific competition, its importance in structuring communities, and influence on the traits of individual species.

It is not often that a century of scholarly activity breaks conveniently into halves, but ornithology of the first half of the 20th century is clearly different from that of the second half. The break actually can be marked in 1949, with the appearance of Meyer and Schuz's Ornithologie ais Biologische Wissenschaft. Prior to this, ornithologists had tended to speak mostly to other ornithologists, experiments (the testing of hy potheses) were uncommon, and a concern for birds as birds was the dominant thread in our thinking. Subsequent to 1949, ornithologists have tended to become ever more professional in their pursuits and to incorporate protocols of experimental biology into their work; more importantly perhaps, they have begun to show a concern for birds as agencies for the study of biology. Many of the most satisfying of recent ornithological studies have come from reductionist research ap proaches, and have been accomplished by specialists in such areas as biochemistry, ethology, genetics, and ecology. A great many studies routinely rely on statistical hypothesis testing, allowing us to come to conclusions unmarred by wishful thinking. Some of us are ready to tell the world that we are a "hard" science, and perhaps that time is not so very far off for most of us. Volume 2 examines several solid examples of late 20th-century ornithology.

A major study of avian community ecology.

Professor Cody's monograph emphasizes the role of competition at levels above single species populations, and describes how competition, by way of the niche concept, determines the structure of communities. Communities may be understood in terms of resource gradients, or niche dimensions, along which species become segregated through competitive interactions. Most communities appear to exist in three or four such dimensions. The first three chapters describe the resource gradients (habitat types, foraging sites, food types), show what factors restrict species to certain parts of the resource gradients and so determine niche breadths, and illustrate the important role of resource predictability in niche overlap between species for resources they share. Most examples are drawn from eleven North and South American bird communities, although the concepts and methodology are far more general. Next, the optimality of community structure is tested through parallel and convergent evolution on different continents with similar climates and habitats, and the direct influence of competitors on resource use is investigated by comparisons of species--poor island communities to species-rich mainland ones. Finally, the author discusses those sorts of environments in which the evolution of one species--one resource set is not achieved, and where alternative schemes of resource allocation, often involving several species that act ecologically as one, must be followed.

Evolutionary biology has long sought to explain how new traits and new species arise. Darwin maintained that competition is key to understanding this biodiversity and held that selection acting to minimize competition causes competitors to become increasingly different, thereby promoting new traits and new species. Despite Darwin’s emphasis, competition’s role in diversification remains controversial and largely underappreciated. In their synthetic and provocative book, evolutionary ecologists David and Karin Pfennig explore competition's role in generating and maintaining biodiversity. The authors discuss how selection can lessen resource competition or costly reproductive interactions by promoting trait evolution through a process known as character displacement. They further describe character displacement’s underlying genetic and developmental mechanisms. The authors then consider character displacement’s myriad downstream effects, ranging from shaping ecological communities to promoting new traits and new species and even fueling large-scale evolutionary trends. Drawing on numerous studies from natural populations, and written for a broad audience, Evolution’s Wedge seeks to inspire future research into character displacement’s many implications for ecology and evolution.

The average person can name more bird species than they think, but do we really know what a bird “species” is? This open access book takes up several fascinating aspects of bird life to elucidate this basic concept in biology. From genetic and physiological basics to the phenomena of bird song and bird migration, it analyzes various interactions of birds – with their environment and other birds. Lastly, it shows imminent threats to birds in the Anthropocene, the era of global human impact. Although it seemed to be easy to define bird species, the advent of modern methods has challenged species definition and led to a multidisciplinary approach to classifying birds. One outstanding new toolbox comes with the more and more reasonably priced acquisition of whole-genome sequences that allow causative analyses of how bird species diversify. Speciation has reached a final stage when daughter species are reproductively isolated, but this stage is not easily detectable from the phenotype we observe. Culturally transmitted traits such as bird song seem to speed up speciation processes, while another behavioral trait, migration, helps birds to find food resources, and also coincides with higher chances of reaching new, inhabitable areas. In general, distribution is a major key to understanding speciation in birds. Examples of ecological speciation can be found in birds, and the constant interaction of birds with their biotic environment also contributes to evolutionary changes. In the Anthropocene, birds are confronted with rapid changes that are highly threatening for some species. Climate change forces birds to move their ranges, but may also disrupt well-established interactions between climate, vegetation, and food sources. This book brings together various disciplines involved in observing bird species come into existence, modify, and vanish. It is a rich resource for bird enthusiasts who want to understand various processes at the cutting edge of current research in more detail. At the same time it offers students the opportunity to see primarily unconnected, but booming big-data approaches such as genomics and biogeography meet in a topic of broad interest. Lastly, the book enables conservationists to better understand the uncertainties surrounding “species” as entities of protection.

After his famous visit to the Galápagos Islands, Darwin speculated that "one might fancy that, from an original paucity of birds in this archipelago, one species had been taken and modified for different ends." This book is the classic account of how much we have since learned about the evolution of these remarkable birds. Based upon over a decade's research, Grant shows how interspecific competition and natural selection act strongly enough on contemporary populations to produce observable and measurable evolutionary change. In this new edition, Grant outlines new discoveries made in the thirteen years since the book's publication. Ecology and Evolution of Darwin's Finches is an extraordinary account of evolution in action. Originally published in 1986. 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.