This dissertation project investigates the operation of female choice of mates in a social environment characterized by male competition. Recent studies of primate species with harem social organization and large differences in size between sexes assume male-male competition is responsible for social structure, rather than female choice. However, an association between polygyny and sex dimorphism does not exist in horses, and dominant harem stallions fail to sire nearly a third of the foals in their bands. This study at Assateague Island will examine four possible female reproductive strategies for feral horses, and will combine detailed field obserations of behavior and social organization withpaternity assignment. These data will allow a better understanding of the mating system of horses and particularly the role of female choice in harem social organizations more generally. The contrast to the usual situation in primates will be very instructive. NSF funds are requested for the genetic laboratory phase of the project, otherwise supported by the Hill Foundation. The project will enhance the training of a young professional.
