The next task is to marshal the evidence, largely from naturalistic studies of wild chimpanzee groups, of how the egalitarian mutual dependence system operates within chimpanzee society. Anthropological understandings regarding the workings of human foraging societies are used to structure this discussion.

An egalitarian society is one in which all members are considered to be of equal intrinsic worth and are entitled to equal access to, and share of, the goods, rights and privileges of their society. Within the structure of such societies, individuals have a high degree of autonomy. Hence power relationships do not exist in societies that are egalitarian in form, nor do inequalities of possessions, prestige and status. The immediate-return foraging system is intensely egalitarian. Indeed, Woodburn (1982:432) emphasizes very strongly that no other system found among humans ‘permits so great an emphasis on equality.’

People who live as foragers are highly ‘individualized;’ they are not equal in the sense of being the same as each other (Service 1966:83). The unspecialized nature of foraging societies means that all adults participate much more fully in every aspect of the society than do members of more complex social systems. Members are accepted as they are, for what they are, in their natural variety, Service emphasizes.

Similarities in overt behavioral manifestations of humans and chimpanzees do not necessarily imply that the phenomenon derives from the same underlying mechanisms. However, the following analysis proceeds on the assumption that, if certain positive behaviors and relationships are intrinsic to foraging humans, they are equally imperative to chimpanzees who follow the same foraging system.