SEXUAL SELECTION AND THE EVOLUTION OF DANCE FLY MATING SYSTEMS (DIPTERA: EMPIDIDAE; EMPIDINAE)

Abstract

AbstractCourtship displays of empidine dance flies (Diptera: Empididae), which include transfers of nuptial gifts during mating, are reviewed in light of sexual selection theory. Sex-role reversed courtship behavior, involving female swarming and male choice, appears to be correlated with certain female secondary sexual characters that are widespread throughout the Empidinae. The tendency to shift mate choice from females to males, and the apparent development of autogeny in many empidine species, are both hypothesized to have resulted from males monopolizing the proteinaceous food source of non-hunting females, through transfers of nuptial gifts of prey. The autogenous condition appears to have led to the ritualized presentation of various types of inedible nuptial gifts by males of several species, possibly including the development of secreted nuptial gifts, or balloons, as displays of male fitness.