9309805 Holekamp Drs. Holekamp and Smale will continue their field study of behavioral development in free- living spotted hyenas. Their goals are (1) to initiate study of the hormonal correlates of aggressive and sexual behaviors in this species as these change at puberty and during adult breeding cycles, and (2) to evaluate effects of social rank on reproduction. The animals being studied are members of one large hyena clan in the Masai Mara National Reserve, Kenya. Age, sex, kin relations, and social status are known for all clan members, and detailed social histories are known for all cubs and subadults currently present in the population. Using observational study, radio telemetry, and laboratory analyses of hormone levels in various biological fluids produced by the study animals, Drs. Holekamp and Smale will collect longitudinal behavioral and hormonal data from both pubertal and adult animals. Endocrine and behavioral data will be used together to test hypotheses about mechanisms by which social rank influences reproductive performance. While the study of reproduction is being initiated, observational and telemetric data-collection will also continue germane to understanding both male dispersal and reproductive success in both sexes. This research project will generate useful information in at least four ways: It will (1) contribute importantly to elucidation of carnivore reproductive biology, (2) provide detailed data on behavioral development and reproductive endocrinology of animals experiencing the full complexity of their natural habitat, (3) enhance understanding of the relationship between hormones and aggressive behavior in female mammals, and (4) yield valuable comparative data revealing how physiological, developmental, functional, and phylogenetic factors interact to shape mammalian social behavior.
