Fighting and playfighting in captive adolescent chimpanzees

Abstract

Most young non-human primates spend a great deal of time playing alone or with conspecifics. Despite numerous studies on social play, its adaptive functions remain unclear. A longitudinal study comparing social interactions preceding and following rank reversals among four captive adolescent chimpanzees (Pan troglodytes schweinfurtii) suggests that social play during their adolescent period functioned in establishing and maintaining the dominance rank within dyads, without interventions from allies. Interventions were less frequent in rough-and-tumble play than in real fighting. Within dyads of competing chimpanzees, rough play was more frequent than gentle play. Both types of play were correlated with reciprocal aggression between competitors, and most play bouts terminated in truly aggressive conflict. Dominant individuals seemed to be responsible for maintaining play activity, by responding playfully to threats and aggression of contestants. In addition, dominant individuals more often initiated play encounters with their subordinates when the dominance relationships were clear, but subordinate individuals also initiated play sequences when they challenged the dominant's rank. The adaptive value and mechanisms of rough-and-tumble play are discussed in the context of adolescence. © 1994 Wiley-Liss, Inc.