As our closest primate relatives, chimpanzees offer tantalizing clues about the behavior of early human ancestors. This book provides a rich and detailed portrait of chimpanzee social life in the wild, synthesizing hundreds of thousands of hours of research at seven long-term field sites. Why are the social lives of males and females so different? Why do groups of males sometimes seek out and kill neighboring individuals? Do chimpanzees cooperate when they hunt monkeys? Is their vocal behaviour like human speech? Are there different chimpanzee 'cultures'? Addressing these questions and more, Adam Arcadi presents a fascinating introduction to the chimpanzee social universe and the challenges we face in trying to save this species from extinction. With extensive notes organized by field site and an appendix describing field methods, this book is indispensable for students, researchers, and anyone else interested in the remarkable and complex world of these intelligent apes.