ABSTRACT PI: Holekamp Proposal Number IBN96-30667: The evolution of intelligence in response to social complexity The primary purpose of this research is to examine predictions of an hypothesis suggesting that the evolution of intelligence in mammals has been driven by selection pressures associated with life in a complex social environment. If this hypothesis is correct, then some or all of the impressive cognitive abilities observed in primates should also occur in non-primate mammals living in primate-like societies. Spotted hyenas (Crocuta crocuta) are large carnivores that live in social groups like those of old-world monkeys. Thus the social complexity hypothesis predicts that spotted hyenas should possess many or all of the same features of social intelligence as do these primates. Here we propose to determine what spotted hyenas know about their social worlds, how they use this knowledge, and how it differs from that described for monkeys by earlier workers. Subject animals are members of one large hyena clan in Kenya. Age, sex, kin relations, and social status are known for all natal animals, and most adult clan members wear radio collars so they can be regularly relocated and observed. Using videotaped responses of hyena subjects to playbacks of recorded vocalizations, we will determine whether hyenas, like monkeys, can discriminate among conspecific vocalizations based on group membership, kinship, and association patterns. A secondary goal of this research is to continue on-going work on hormone-behavior relationships in free- living hyenas, and to supplement this with preliminary analyses of patterns of variation in their immune system function. This research will generate three types of useful information: it will (1) elucidate the functions of animal intelligence in the natural habitat, as well as the selection pressures favoring its evolution, (2) yield rare data documenting the extent of variation in disease exposure and immunocompetence among wild animals, and (3) enhance understanding of carnivore social behavior and immunocompetence to facilitate decision-making by wildlife managers and others concerned with biodiversity and conservation of African ecosystems.
