Mate choice copying in Drosophila is probably less robust than previously suggested

Abstract

Female mate choice copying is a form of social learning wherein females preferentially mate with partners similar to those they had previously observed mating with other females. The phenomenon is well established in many vertebrate species and some arthropods. Among insects, only one species, the fruit fly Drosophila melanogaster, has been shown to perform female mate choice copying under experimental conditions using two artificial male phenotypes (males dusted with powders of different colours). Moreover, this species has been shown to be capable of maintaining mate choice traditions, at least in laboratory conditions. In the present study, however, we failed to obtain unambiguous support for the claim that virgin female Drosophila (‘observers’) tend to prefer males of the same artificial phenotype as that chosen by another female (‘demonstrator’). The discrepancy is probably because our experiments differed in a number of seemingly minor details from the published experimental procedures. The results indicate that female mate choice copying in Drosophila is probably less robust than the present body of literature suggests, and that more research is needed to assess the prevalence of this phenomenon in different laboratory lines and natural populations of fruit flies.