Juichi Yamagiwa – författare

In this book, the editors present a view of the socioecology of primates and cetaceans in a comparative perspective to elucidate the social evolution of highly intellectual mammals in terrestrial and aquatic environments. Despite obvious differences in morphology and eco-physiology, there are many cases of comparable, sometimes strikingly similar patterns of sociobehavioral complexity. A number of long-term field studies have accumulated a substantial amount of data on the life history of various taxa, foraging ecology, social and sexual relationships, demography, and various patterns of behavior: from dynamic fission–fusion to long-term stable societies; from male-bonded to bisexually bonded to matrilineal groups.

Primatologists and cetologists have come together to provide four evolutionary themes: (1) social complexity and behavioral plasticity, (2) life history strategies and social evolution, (3) the interface between behavior, demography, and conservation, and (4) selected topics in comparative behavior. These comparisons of taxa that are evolutionarily distant but live in comparable complex sociocognitive environments boost our appreciation of their sophisticated mammalian societies and can advance our understanding of the ecological factors that have shaped their social evolution. This knowledge also facilitates a better understanding of the day-to-day challenges these animals face in the human-dominated world and may improve the capacity and effectiveness of our conservation efforts.

Why do females in male-philopatric species seem to show larger variation in their life history strategies than males in female-philopatric species? Why did females in human societies come to show enormous variation in the patterns of marriage, residence and mating activities?

To tackle these important questions, this book presents the latest knowledge about the dispersing females in male-philopatric non-human primates and in human societies. The non-human primates that are covered include muriquis, spider monkeys, woolly monkeys, gorillas, chimpanzees, bonobos and some species of colobine monkeys. In these non-human primate species females typically leave their natal group before sexual maturation and start reproduction in other groups into which they immigrate. However, there is a large variation as some females may breed in their natal group with some risks of inbreeding with their male relatives and some females may associate with males of multiple groups at the same time after leaving their natal group. Such variation seems to provide better strategies for reproduction depending on local circumstances. Although knowledge about female dispersal patterns and life history is indispensable for understanding the dynamic structure of primate societies, it is still not known how females behave after leaving their natal groups, how many groups they visit before finally settling down and which kinds of groups they choose to immigrate into, due to the large variation and flexibility and the difficulty of tracking females after natal dispersal.

To encourage further progress in this important field, this volume provides new insights on evolution of female dispersal by describing factors influencing variations in the dispersal pattern across primates and a hypothesis for the formation of human families from the perspectives of female life history. This book is recommended reading for researchers and students in primatology, anthropology, animal behavior and evolution and for anyone interested in primate societies and human evolution.