Mate choice increases a component of offspring fitness in fruit flies

Abstract

The authors of two influential accounts of the genetic consequences of mate choice consider that animals cannot produce fitter offspring by mating with a fitter than average individual^1,2. Their main reason for this is that in a population at genetic equilibrium any genetic variation which affects fitness should not be heritable³. Other accounts have suggested ways in which mate choice might improve offspring fitness⁴. Data are now presented which show that one component of offspring fitness can be increased by mate choice in Drosophila melanogaster. The component of fitness measured was intraspecific competitive success during the part of the life history from first instar larva to adult fly.