Cuticular Hydrocarbon Content that Affects Male Mate Preference ofDrosophila melanogasterfrom West Africa

Abstract

Intraspecific variation in mating signals and preferences can be a potential source of incipient speciation. Variable crossability betweenDrosophila melanogasterandD. simulansamong different strains suggested the abundance of such variations. A particular focus on one combination ofD. melanogasterstrains, TW1(G23) and Mel6(G59), that showed different crossabilities toD. simulans, revealed that the mating between females from the former and males from the latter occurs at low frequency. The cuticular hydrocarbon transfer experiment indicated that cuticular hydrocarbons of TW1 females have an inhibitory effect on courtship by Mel6 males. A candidate component, a C25 diene, was inferred from the gas chromatography analyses. The intensity of male refusal of TW1 females was variable among different strains ofD. melanogaster, which suggested the presence of variation in sensitivity to different chemicals on the cuticle. Such variation could be a potential factor for the establishment of premating isolation under some conditions.