Social rejection, exclusion and shunning among the Gombe chimpanzees

From the observations at Gombe over the past 23 years it appears that group punishment of deviant behavior through ostracism, as practiced in human groups, has not yet evolved in a truly sophisticated way in chimpanzee society. However, cases of “social rejection or exclusion” have been observed in three different behavioral contexts. Most frequently, a chimpanzee is the target of hostility as the result of competitive interaction within the community; in such cases, social cohesion counterbalances rejection, typically leading to integration within a relatively stable pattern of dominance and social interaction. The occasional departure of an individual who has been the target of aggression —like the withdrawal of Evered after repeated attacks by Figan and Faban—seems due to persistent hostility by a few males rather than general “ostracism” by the group as a whole. A second form of exclusion concerns outsiders found in the home range of the group: in these cases, hostility is more generalized, particularly in response to the attempt of an adult female with offspring to join the community. Finally, there are the rarely observed instances of shunning a group member whose behavior seems abnormal the social rejection of Pepe and Old Mr. McGregor after they suffered from polio.