The effect of resource subdivision on genetic variation in Drosophila.

Abstract

In Drosophila and other insects utilizing discrete, subdivided breeding sites, only a few females often contribute progeny to a site; this may lead to different levels of genetic variance within a site. Experiments with mixed and pure cultures often indicate that the fitness of a genotype is related to the genetic variance. A simple model is presented in which a subdivided population structure can lead to a protected polymorphism. The effect of subdivision on the increase of a rare allele falls off rapidly as more females contribute to a site. Electrophoretic data for D. melanogaster emerging from rotting apples are used to obtain an estimate of 2-3 females contributing to a breeding site, w..