Play and social relationships in the meerkat (Suricata suricatta)

[摘要] ENGLISH ABSTRACT: Despite more than three decades of research, and the postulation of more than 30 hypothesesof function, the adaptive significance of play remains unknown. This study quantitativelyevaluated a selection of hypotheses of function, using data collected from a wild populationof small, social carnivore, the meerkat, Suricata suricatta. The study found that although playin meerkats carried an energetic cost, with individuals modulating their frequency of play inresponse to their energy intake, none of the hypotheses evaluated by the study could identifythe adaptive benefits that meerkats derived from play. Play did not increase 'social harmony'by reducing aggression between playmates, nor did it strengthen an individual's bonds to itssocial group, such that it remained in the group for longer, or contributed more to the group'scooperative activities. There was no evidence that meerkats used play to strengthen alliancesbetween individuals, and young meerkats played no more frequently with their futuredispersal partners than with matched controls with which they did not disperse. Play fightingexperience did not improve a meerkat's subsequent fighting skills, and individuals thatultimately won the dominant breeding position within a group (through serious fighting)played no more frequently, and no more successfully, as youngsters, than the littermates thatthey defeated in combat. Although play was inhibited by aggression, meerkats did not useplay to contest, assert or establish dominance status, and there was little evidence to suggestthat the preference young meerkats showed for play partners that were well matched in age,size and ability arose from their use of play for self-assessment.This study assessed only those hypotheses of function that predicted benefits that were ofimportance to the inclusive fitness of the study species. For example, the enhancement ofsocial harmony and group cohesion should be invaluable to a species whose survival isdependent upon social cooperation; and the high reproductive skew exhibited by this speciesplaces huge value upon fighting skill and the ability to win social dominance. As aconsequence, this study's negative findings suggest strongly that play is not capable ofproviding these benefits, and that play behaviour is unlikely to be used for these purposes inany mammal species. I conclude that the most likely function of play (based on play'subiquitous characteristics, and the findings of neurological research on rats) is the promotionof growth of the cerebral cortex.

[发布机构] Stellenbosch University