Contributors to this volume offer new research on extinction processes in birds, nest predation, and song systems, and describes a graphical model that helps predict the reproductive consequences of time allocation between the competing demands of guarding young birds and foraging for food. Current Ornithology is the only English-language publication currently devoted exclusively to extensive reviews and synthesis of topics pertaining to all aspects of the biology of birds. Chapters fall under such diverse rubrics as ecology, evolution, behavior, phylogeny, behavioral ecology, anatomy and physiology, and conservation biology. All authors are leading authorities on their subjects, and each chapter is refereed by experts in the topics covered. Although all chapters focus primarily on birds, some topics, such as the social cognition of birds as compared to primates (Volume 13), have significant application to disciplines outside of ornithology. Current Ornithology aims to provide an accessible, up-to-date, accurate source of data and to contribute to conceptual generalization and unification across the biological sciences.

This edited series has three principal goals. The first is to provide information in a relatively concise way for researchers needing an over view of specific disciplines. The second is to provide an update on specific schools of thought, bringing together ideas from colleagues whose works often appear in a variety of journals. And the third is to stimulate and suggest directions for new research. Volume 6 continues the tradition established by the previous editor and editorial board in providing new information, updating our understanding of specific dis ciplines, and stimulating new research. In the first chapter, Randall Breitwisch examines mortality patterns and sex ratios in monogamous birds. He argues that there are many more components to measuring parental investment than are often re alized; our knowledge is weak in several areas. Understanding the evo lution of mating systems depends on better distinguishing the different intensities of natural selection that operate on males and females. Greg ory Butcher and Sievert Rohwer develop a framework for assessing the role of colorfulness in birds. They propose several hypotheses to test and advocate evaluating more than one hypothesis at a time. Future work on the evolution of distinctive coloration and of sexual and age dimorphism must take these ideas into account."

This is the only English-language publication devoted exclusively to extensive reviews and synthesis of topics on the biology of birds. The current volume includes articles on sibling competition, predation and the limitation of bird numbers, and population trends in birds of eastern North America.

Papers presented at the 20th meeting of the International Ornithological Congress held in New Zealand, December 1990 emphasizing New Zealand and the southern Pacific Ocean. Topics include: a summary of ornithological work in New Zealand, enemy recognition and response, parasitism and sexual selectio

Eight papers on various aspects of the subject, including: declines in migratory birds; avian energy storage; survival rates of British birds; food storing in birds; social organization in Parus; age-specific variation and reproduction; evolution of coloniality; and extra-pair copulations. Annotati

In Volume 12, eminent international ornithologists further elucidate endocrinological correlates of mating strategies and hormones and reproductive behavior; assess the value of the "brood reduction hypothesis" in explaining "the paradox of hatching asynchrony"; and explore the validity and sensitivity of growth bands in feathers as an indication of nutritional condition and the use of feather banding in studying growth. Chapters in this book are well supported with charts, maps, schematic diagrams, and photographs. "Current Ornithology" is the only English-language publication currently devoted exclusively to extensive reviews and synthesis of topics pertaining to all aspects of the biology of birds. Chapters fall under such diverse rubrics as ecology, evolution, behavior, phylogeny, behavioral ecology, anatomy and physiology, and conservation biology. All authors are leading authorities on their subjects, and each chapter is refereed by experts in the topics covered. Although all chapters focus primarily on birds, some topics, such as the social cognition of birds as compared to primates (Volume 13), have significant application to disciplines outside of ornithology. "Current Ornithology" aims to provide an accessible, up-to-date, accurate source of data and to contribute to conceptual generalization and unification across the biological sciences.

This edited series has three principal goals. The first is to provide information in a relatively concise way for researchers needing an over view of specific disciplines. The second is to provide an update on specific schools of thought, bringing together ideas from colleagues whose works often appear in a variety of journals. And the third is to stimulate and suggest directions for new research. Volume 6 continues the tradition established by the previous editor and editorial board in providing new information, updating our understanding of specific dis ciplines, and stimulating new research. In the first chapter, Randall Breitwisch examines mortality patterns and sex ratios in monogamous birds. He argues that there are many more components to measuring parental investment than are often re alized; our knowledge is weak in several areas. Understanding the evo lution of mating systems depends on better distinguishing the different intensities of natural selection that operate on males and females. Greg ory Butcher and Sievert Rohwer develop a framework for assessing the role of colorfulness in birds. They propose several hypotheses to test and advocate evaluating more than one hypothesis at a time. Future work on the evolution of distinctive coloration and of sexual and age dimorphism must take these ideas into account."

This is the only English-language publication devoted exclusively to extensive reviews and synthesis of topics on the biology of birds. The current volume includes articles on sibling competition, predation and the limitation of bird numbers, and population trends in birds of eastern North America.

Detailing novel research methods, this compilation presents major advances in fundamental aspects of phylogeny, mating, parental care, the trophic structure of Raptor communities, demography, behavioral ecology, species diversity, and the evolution of avian ontogenies. The book also features the most extensive list of international references available on raptor diet and feeding behavior and nocturnality. Current Ornithology is the only English-language publication currently devoted exclusively to extensive reviews and synthesis of topics pertaining to all aspects of the biology of birds. Chapters fall under such diverse rubrics as ecology, evolution, behavior, phylogeny, behavioral ecology, anatomy and physiology, and conservation biology. All authors are leading authorities on their subjects, and each chapter is refereed by experts in the topics covered. Although all chapters focus primarily on birds, some topics, such as the social cognition of birds as compared to primates (Volume 13), have significant application to disciplines outside of ornithology. Current Ornithology aims to provide an accessible, up-to-date, accurate source of data and to contribute to conceptual generalization and unification across the biological sciences.

In Volume 12, eminent international ornithologists further elucidate endocrinological correlates of mating strategies and hormones and reproductive behavior; assess the value of the ''brood reduction hypothesis'' in explaining ''the paradox of hatching asynchrony''; and explore the validity and sensitivity of growth bands in feathers as an indication of nutritional condition and the use of feather banding in studying growth. Chapters are well supported with charts, maps, schematic diagrams, and photographs. Current Ornithology is the only English-language publication currently devoted exclusively to extensive reviews and synthesis of topics pertaining to all aspects of the biology of birds. Chapters fall under such diverse rubrics as ecology, evolution, behavior, phylogeny, behavioral ecology, anatomy and physiology, and conservation biology. All authors are leading authorities on their subjects, and each chapter is refereed by experts in the topics covered. Although all chapters focus primarily on birds, some topics, such as the social cognition of birds as compared to primates (Volume 13), have significant application to disciplines outside of ornithology. Current Ornithology aims to provide an accessible, up-to-date, accurate source of data and to contribute to conceptual generalization and unification across the biological sciences.