Analysis of impact of infanticide on social organization and reproductive behavior in primates including humans.

Recent field studies of a variety of mammalian species reveal a surprisingly high frequency of infanticide--the killing of unweaned or otherwise maternally dependent offspring. Similarly, studies of birds, fish, amphibians, and invertebrates demonstrate egg and larval mortality in these species, a phenomenon directly analogous to infanticide in mammals. In this collection, Hausfater and Hrdy draw together work on animal and human infanticide and place these studies in a broad evolutionary and comparative perspective. Infanticide presents the theoretical background and taxonomic distribution of infanticide, infanticide in nonhuman primates, infanticide in rodents, and infanticide in humans. It examines closely sex allocation and sex ratio theory, surveys the phylogeny of mammalian interbirth intervals, and reviews data on sources of egg and larval mortality in a variety of invertebrate and lower vertebrate species. Dealing with infanticide in nonhuman primates, two chapters critically examine data on infanticide in langurs and its broader theoretical implications. By reviewing sources of infant mortality in populations of small mammals and new laboratory analyses of the causes and consequences of infanticide, this work explores such issues as the ontogeny of infanticide, proximate cues of infants and females which elicit infanticidal behavior in males, the genetical basis of infanticide, and the hormonal determinants. Hausfater and Sarah Blaffer Hrdy, through their selection of materials for this book, evaluate the frequency, causes, and function of infanticide. Historical, ethnographic, and recent data on infanticide are surveyed. Infanticide summarizes current research on the evolutionary origins and proximate causation of infanticide in animals and man. As such it will be indispensable reading for anthropologists and behavioral biologists as well as ecologists, psychologists, demographers, and epidemiologists. Glenn Hausfater was professor at the division of biological sciences at the University of Missouri-Columbia. He is the author of Guidebook for the Long-Term Monitoring of Amboseli Baboons and their Habitat; Dominance and reproduction in Baboons; and Early Vegetation of the Illinois Valley. Sarah Blaffer Hrdy is professor emeritus of anthropology at the University of California, Davis. She is the author of The Woman that Never Evolved; The Langurs of Abu; and The Black-Man of Zinacantan.

This book presents extensive field research and analysis to evaluate sexual coercion in a range of species—including all of the great apes and humans—and to clarify its role in shaping social relationships among males, among females, and between the sexes.

"A subject collection from Cold Spring Harbor Perspectives in Biology."

What happens to a society that has too many men? In this provocative book, Valerie Hudson and Andrea den Boer argue that, historically, high male-to-female ratios often trigger domestic and international violence. Most violent crime is committed by young unmarried males who lack stable social bonds. Although there is not always a direct cause-and-effect relationship, these surplus men often play a crucial role in making violence prevalent within society. Governments sometimes respond to this problem by enlisting young surplus males in military campaigns and high-risk public works projects. Countries with high male-to-female ratios also tend to develop authoritarian political systems. Hudson and den Boer suggest that the sex ratios of many Asian countries, particularly China and India—which represent almost 40 percent of the world's population—are being skewed in favor of males on a scale that may be unprecedented in human history. Through offspring sex selection (often in the form of sex-selective abortion and female infanticide), these countries are acquiring a disproportionate number of low-status young adult males, called "bare branches" by the Chinese. Hudson and den Boer argue that this surplus male population in Asia's largest countries threatens domestic stability and international security. The prospects for peace and democracy are dimmed by the growth of bare branches in China and India, and, they maintain, the sex ratios of these countries will have global implications in the twenty-first century.

In 1987, the University of Chicago Press published Primate Societies, the standard reference in the field of primate behavior for an entire generation of students and scientists. But in the twenty-five years since its publication, new theories and research techniques for studying the Primate order have been developed, debated, and tested, forcing scientists to revise their understanding of our closest living relatives. Intended as a sequel to Primate Societies, The Evolution of Primate Societies compiles thirty-one chapters that review the current state of knowledge regarding the behavior of nonhuman primates. Chapters are written by the leading authorities in the field and organized around four major adaptive problems primates face as they strive to grow, maintain themselves, and reproduce in the wild. The inclusion of chapters on the behavior of humans at the end of each major section represents one particularly novel aspect of the book, and it will remind readers what we can learn about ourselves through research on nonhuman primates. The final section highlights some of the innovative and cutting-edge research designed to reveal the similarities and differences between nonhuman and human primate cognition. The Evolution of Primate Societies will be every bit the landmark publication its predecessor has been.

Sexual combat is not a monopoly of the human species. As Sarah Blaffer Hrdy argues in this spellbinding book, war between male and female animals has deep roots in evolutionary history. Her account of family life among hanuman langurs--the black-faced, gray monkeys inhabiting much of the Indian subcontinent--is written with force, wit, and at times, sorrow. Male hanumans, in pursuit of genetic success, routinely kill babies sired by their competitors. The mothers of endangered infants counter with various strategems to deceive the males and prevent destruction of their own offspring. Competition and selfishness are dominant themes of langur society. Competition among males for access to females, competition among females for access to food resources, and disregard by one female for the well-being of another's infant--these are some very common examples. Yet there are also moments of heroic self-sacrifice, as when an elderly female rushes to defend her troop and its babies from an invading, infancticidal male. The Langurs of Abu is the first book to analyze behavior of wild primates from the standpoint of both sexes. It is also a poignant and sophisticated exploration of primate behavior patterns from a feminist point of view. This book may inspire controversy; it will certainly be read with pleasure by anyone interested in animal behavior. Richly illustrated with photographs, seven in full color.