CARSTEN, LD; PAPAJ, DR; University of Arizona; University of Arizona: Sexual conflict and dynamic mating decisions in walnut flies (Rhagoletis juglandis)

Conflict can arise between mating partners over reproductive decisions such as length and frequency of copulation. The mating decisions of both sexes can be influenced by context and state dependent factors such as social milieu, age, and reproductive condition. For instance, a reproductively mature female may represent a more valuable resource to a male than an immature female, and thus, he may invest more in a mature female. This investment could take the form of mate guarding, long copulations, or higher amount of sperm transfer, any of which may or may not be in the best interests of the female. We examined dynamic mating decisions in relation to female reproductive condition (egg load) and host experience in the walnut fly, Rhagoletis juglandis. We found that both reproductive condition and host experience affect mating behavior. Moreover, different components of mating behavior respond to host experience and reproductive condition in different ways, with host experience influencing copulation duration, and egg load influencing propensity to copulate. Our results are consistent with the female perspective with respect to copulation duration, but with the male perspective with respect to propensity to copulate. This pattern implies that copulation duration was under female control, but the decision to copulate in the first place was under male control.