Fitness components in a Vestigial Mutant Strain of Drosophila Melanogaster

Abstract

An experiment was performed to investigate the genetic and behavioural mechanisms responsible for the persistance of the vestigial phenotype in a laboratory mixed population of Drosophila melanogaster. Successive backcrosses between a vestigial and a wild strain, determining modifications of the vg’s genetic background, produced an increase of its reproductive fitness. Nevertheless, the homogeneity of fitness between the two phenotypes is not sufficient to guarantee the equilibrium in a mixed population. Behavioural factors related to sexual attraction and not to size and shape differences, by promoting heterogeneous matings, induce a decrease of the vg individuals. In particular, a pheromonal control of mating patterns is thought to function as a recognition mechanism in selective matings. © 1986 Taylor & Francis Group, LLC.