Genomic architecture of the developing forelegs of Drosophila prolongata; an exaggerated weapon and ornament

Functional genetic studies of these phenotypes generally focus on within-species analyses of candidate signalling pathways. These provide insight into mechanisms of trait expression, but not necessarily genetic differences contributing to evolutionary change.

Drosophila prolongata offers an exceptional model to explore the evolution of trait exaggeration, as the only known species with male-specific foreleg size exaggeration in the melanogaster species group. We used sex-specific RNA-seq in fore- and midleg developing organs (imaginal discs) sampled at both the onset, and just after initiation of, sexually dimorphic growth between these tissues in D. prolongata. We sampled equivalent developmental tissues & stages in D. carrolli (~4MYA divergence) and D. melanogaster (~35MYA).