Sexual Selection in Tephritid Fruit Flies and Its Implication in the Sterile Insect Release Method

Abstract

Our observations of the complex mating system of natural populations (under totally natural conditions; i.e. in contrast to field-cage conditions) of tephritid species indicate that sexual selection via female choice operates as a powerful force in regulating the effective reproductive population. We have found that for both the medfly, Ceratitis capitata, and the melon fly, Dacus cucurbitae, approximately 25 – 30% of the males accomplish more than 50% of the matings. Equally important is the observation that as many as 30% of the males may never mate while in competition with behaviorally superior males. These findings indicate differential mating success among males and that sexual selection is further intensified by the lek mating system (Arita and Kaneshiro, 1989) observed in these species.