REPRODUCTIVE ISOLATION AND THE PERIOD GENE OF DROSOPHILA

The identification of genes of large effect on ecologically important traits is an important aim of molecular ecology. The period gene of Dr osophila is a candidate for a gene with a large influence on premating isolation between Drosophila species, as it determines species specif ic aspects of courtship behaviour. Strains of D. melanogaster are avai lable which have been genetically transformed with the period gene of either D. melanogaster or D. simulans. Here we show that D. melanogast er females do not discriminate between two such strains. This suggests that period may only make a small contribution to total premating iso lation between these species. We discuss the use of genetically transf ormed strains in assessing the influence of single genes on complex tr aits.