When are vomiting males attractive? Sexual selection on condition-dependent nuptial feeding in Drosophila subobscura

Nuptial gifts are any nutritious items or inedible tokens transferred from the male to the female as a part of courtship or copulation. Although nuptial gift donation has been studied in a variety of taxa, this behavior has been largely overlooked in Drosophila. We studied nuptial feeding in Drosophila subobscura, where the gift is a regurgitated drop of liquid, in order to examine the importance of this behavior for male mating success and female fecundity. We varied male and female condition by dietary restriction to assess any condition dependence of male nuptial feeding ability and female feeding behavior and mate discrimination. Our results show that there was directional selection for…