Non-Monogamous Copulations and Potential Within-Group Mating Competition in White-Faced Saki Monkeys (Pithecia pithecia)
Creator
Thompson C L
Publisher
American Journal of Primatology
Date
2013
2013-08
Description
Many primates display within-species variation in social organization and mating system. Individuals of these species may be confronted with both the challenges of between-group competition to exclude same-sex competitors as well as within-group competition for mating opportunities. Free-ranging white-faced saki monkeys (Pithecia pithecia) live in both male-female pairs and small multi-male, multi-female groups. Despite commonly held views that this species is monogamous, there are currently no published accounts of mating patterns in the genus Pithecia. I recorded copulations and sexual behavior from three free-ranging groups of white-faced sakis at Brownsberg Naturepark, Suriname over a period of 17 months. Groups displayed both monogamous and polygynandrous mating. Individuals in polygynandrous groups were not observed to mate more frequently with certain partners. Copulation harassment occurred in 8.6% of copulations (total N=81) and was performed by both sexes. This harassment successfully prevented ejaculation in six out of seven instances and harassment by males resulted in male-male aggression on four occasions. Two cases of female-directed sexual aggression by males were also observed, which may indicate that males use sexual coercion to influence female mating behavior. Although based on a small number of groups, these data show that white-faced sakis display variability in mating system and that this variability is not directly dictated by social organization. Furthermore, groups with promiscuous copulations exhibit behaviors indicative of within-group mating competition. Am. J. Primatol. 75:817-824, 2013. (c) 2013 Wiley Periodicals, Inc.
Subject
aggression; behavior; group-dynamics; harassment; japanese macaques; mating harassment; mating system; multimale; pair living; primate; sexual coercion; social-organization; social-organization; sperm; Zoology