Meeting Abstract

S4-9  Sunday, Jan. 5 13:30 - 14:00  Social competition and cooperation affect reproductive success of female spotted hyenas HOLEKAMP, K. E.*; MONTGOMERY, T. M.; STRAUSS, E. D.; Michigan State University; Michigan State University; University of Nebraska

The reproductive biology of many female mammals is affected by their social environment and their interactions with conspecifics. In mammalian societies structured by linear dominance hierarchies, such as that of the spotted hyena (Crocuta Crocuta), a female’s social rank can have profound effects on both her reproductive success and her longevity. In this species social rank determines priority of access to food, but it also affects females’ use of space, energetics, growth, den attendance and social networks. Rank effects appear to be mediated in part by nutrition, prenatal androgen exposure and immune function. Infanticide by higher-ranking females may also function to suppress reproduction in subordinate females. Despite the apparent costs of gregariousness to low-ranking females, gregariousness can also have positive effects on their fitness. These positive effects appear to result from having female allies, both kin and non-kin, who cooperate to advertise and defend a shared territory, acquire and defend food resources, maintain the status quo, and sometimes also to rise in social rank.