Mate copying in Drosophila simulans

To facilitate the search for a suitable mating partner, many animals across all taxa use social information. One form of social learning is mate copying, in which individuals use information about potential mates by copying the mate choices of other individuals. While many studies have documented mate copying in Drosophila melanogaster and its potential for cultural evolution in the laboratory, little is known about mate copying in other Drosophila species. Here we report the first evidence that Drosophila simulans females can also acquire a sexual preference for a particular trait of a male after observing a single mating event. We used the same protocol developed for D. melanogaster: A naïve, unmated female first observes a conspecific's mate choice between one artificially colored green and one artificially colored pink male, and is subsequently allowed to choose between two males of the same phenotype herself. Just as with D. melanogaster, D. simulans females were more likely to choose the same type of male as in the demonstration. Thus, D. simulans females are capable of rapid social observational learning, and this highlights the potential importance of mate copying, a trait that may contribute to reproductive isolation.