GENETIC-VARIABILITY OF THE INTERPULSE INTERVAL OF COURTSHIP SONG AMONG SOME EUROPEAN POPULATIONS OF DROSOPHILA-MELANOGASTER

The interpulse interval of the courtship song of Drosophila melanogast er is a character which may play a significant role in mating success and reproductive isolation. Here we examine the variability of interpu lse interval among replicated laboratory strains of D. melanogaster. T here is no significant variation among populations of different geogra phical origin. This suggests that interpulse interval is subject to st rong selection, as the populations are known to differ for other chara cters. One population, however, was sufficiently different to allow ag enetic analysis. Reciprocal F(1)s and backcrosses implied that the var iance was predominantly additive and autosomal. Possible sources of se lection on interpulse interval are discussed.