This innovative book challenges the perceived view, based largely on long observation of artificially fed chimpanzees in Gombe and Mahale National Parks, Tanzania, of the normal social behavior of chimpanzees as aggressive, dominance seeking, and fiercely territorial. In polar opposition, all reports from naturalistic (nonfeeding) field studies are of nonaggressive chimpanzees living peacefully on home ranges in fluid, open, nonhierarchical groups. This research has been largely ignored and downgraded by most of the scientific community. By utilizing the data from these studies, the author is able to construct a model of an egalitarian form of social organization, based on a role relationship of mutual dependence among many charismatic chimpanzees of both sexes and other more dependent members. This highly and necessarily positive mututal dependence system is characteristic of both undisturbed chimpanzees and humans who live or lived by the "immediate-return" foraging system.