DIFFERENCES IN PLAY DEVELOPMENT OF YOUNG CHIMPANZEES REARED IN FAMILY GROUPS AND IN PEER GROUPS

摘要

Rhesus and chimpanzee infants reared in family conditions showed higher levels of dominance and activity behaviours than infants reared only with their mother or with peers only. These results suggest that the greater the variety of social partners in a rearing condition, the more the individuals are able to develop social skills that will be advantageous to them in group life. We investigated how living in groups with peers only (n = 65) influenced behaviour development in chimpanzees aged from zero to ten years. Comparisons were made with the development of chimpanzees in the same age range in a semi-natural zoo group (n = 25). We expected that young chimpanzees reared in a family group, which offers more variation in social partners than a peer group, would show more frequent and diverse social behaviour; i.e. more social play, more triadic interactions (in play) and more sex differentiation in play, than young chimpanzees reared in peer groups.