A comparison of aggressive play and aggression in free-living baboons, Papio anubis.

A quantitative comparison is given of aggressive play and aggression in terms of the duration and type of movement patterns employed, and the relationships between individuals. The mean length of contact in play was greater than in aggression, whereas chases tended to be longer in adult male aggression than in play, Linear hierarchies describing the overall direction of interactions between individuals were divisible into two sorts, according to the frequency with which roles were reversed. The regions of the body bitten and the proportions in which six types of movement pattern were used were related to the type of hierarchy involved. The results are discussed with reference to the possible functions of social play in the development of movement patterns and individual relationships.