Variation in male courtship song traits in Drosophila virilis: the effects of selection and drift on song divergence at the intraspecific level.

Genetic and phenotypic divergence of Drosophila virilis laboratory strains originating from different parts of the species range were studied with the aid of microsatellite markers and by analysing male courtship songs. The strains from America, Europe, continental Asia and Japan showed moderate geographic clustering both at the genetic level and in several traits of the male song. The genetic distances and the song divergence of the strains did not show significant association, which suggests that the songs have not diverged solely as a side-effect of genetic divergence.

Complex inheritance of male courtship song characters in Drosophila virilis.

We analyzed the inheritance of two male courtship song characters, number of pulses in a pulse train, and length of a pulse train in Drosophila virilis. Biometric analyses of song differences among 16 crosses over three generations (parental and reciprocal F1, F2, and backcrosses) were performed using two different approaches. The joint scaling test revealed significant additive and dominance components, and also significant additive interaction between maternal and progeny genotypes.

Nucleotide and repeat length variation at the nonA gene of the Drosophila virilis group species and its effects on male courtship song.

Genes found to affect male courtship song characters in Drosophila melanogaster are good candidates when tracing genes responsible for species-specific songs in other Drosophila species. It has previously been shown that Thr-Gly repeat length variation at the period gene affects song traits in D. melanogaster, which gives the repetitive regions a special interest.