Reciprocal exchange in chimpanzees and other primates

Abstract

A central problem in the study of animal behavior concerns why individuals cooperate and exchange altruistic acts (Dugatkin 1997). Considerable theoretical attention has focused on explaining the evolution of cooperation and altruism in taxa as diverse as insects and primates (Hamilton 1964a, 1964b, Trivers 1971, Brown 1983). Empirically, cooperation among males generates substantial interest because the resource over which they primarily compete, females, is not easily divided and shared (Trivers 1972).