Doctor of Philosophy
Date of Defense
Bette Loiselle, PhD
Understanding what determines male reproductive success is central to sexual selection theory. The main goal of this dissertation was to examine the processes that shape female mate choice and male reproductive success in an exploded lek species: the White-crowned Manakin (Pipra pipra). The first chapter examined if females select males with certain genetic characteristics to gain indirect fitness benefits. Specifically, it tested whether females preferentially mate with unrelated males or males with high overall heterozygosity to increase the genetic diversity of their offspring. The second chapter examined if food resources within territories affect male mating success of territory owners. This chapter evaluated if resources within territories influenced male mating success by increasing (1) the encounter probability among sexes or (2) male attractiveness during mate choice (by increasing male performance or acting as honest signals of male quality). The third chapter examined the effect of male behavioral traits (i.e., intra and inter-sexual selection traits) and territorial characteristics on male mating success. More specifically, it tested if male traits such as vocalization rate, display rate, territory attendance, aggressive interactions, male-male agonistic interaction, territory size and location have an influence in male mating success. My results suggest that female mate choice is the main mechanism affecting male reproductive success in White-crowned Manakins. Moreover, genetic, ecological and behavioral factors interact to influence the outcomes of male reproductive success. Resources within territories were found to influence male advertisement traits (i.e., display) used during mate selection. Further, females appear to use a combination of genetic and behavioral traits as cues during mate choice. These results highlight the importance of considering multiple factors and their interactions when studying male reproductive success.
Tori, Wendy P., "Sexual selection in a species with exploded leks: the White-crowned Manakin (Pipra pipra)" (2009). Dissertations. 514.