Reactions of adult and immature squirrel monkeys to intergroup exposure

Initial encounters between unfamiliar animals raise the practical problem o f controlling aggression and provide the opportunity to examine changes in social structure that may occur as groups merge. Social interactions and sp atial grouping patterns were examined in newly formed squirrel monkey group s, in which a subgroup of familiar adults was introduced to a subgroup of f amiliar immature squirrel monkeys. Yearlings (10-11 months) and subadults ( 20-50 months) generally remained spatially distinct from adults, and interg roup interactions often consisted of adult-initiated antagonism. Adults exh ibited sexual segregation in their spatial grouping patterns and interactio ns, whereas yearlings and subadults generally showed sexual integration. Th ese data suggest that there is considerable adult resistance to integration of unfamiliar immatures into established adult social groups. (C) 1998 Wil ey-Liss, Inc.