The black swallowtail (Papilio polyxenes) exhibits a hilltopping lek mating system. Lek behavior occurs where males cannot economically defend either females or resources important to females. Males that are more successful in male-male competition or possessing unique qualities attractive to females often do most of the mating. Since females gain nothing but gametes from lek males, leks provide an excellent opportunity to test questions relating to male intrasexual selection and female choice. Choosy females may gain by producing offspring that survive and mature better than those of less selective females. Also, choosy females may produce sons that are more successful in male-male competition or are more preferred by selective females. However, whether females actually gain reproductively through their mate choice in lek-mating species remains largely hypothetical. Using descriptive and experimental techniques, Lederhouse and Scriber will investigate the importance of female intersexual selection (mate choice) and of male-male intrasexual selection (competition) in determining reproductive success in P. polyxenes. They will determine physical and possible genetic correlates of aggressive territorial males with male mating success. The nature and degree of female choice will be determined. The maturation and survival of their offspring and the ability of sons to gain and maintain territories and court females will be compared. The investigators will also test if male reproductive success is correlated to specific genetic profiles. Results of this research will improve understanding of the evolution of leks by testing several alternative views.
