Mate copying in Drosophila simulans

To find a suitable mate, many animals across taxa use social information. Mate copying is a form of social learning in which individuals use information regarding potential mates by observing and copying the mate choices of other individuals. While mate copying in Drosophila melanogaster has been extensively documented in the laboratory and its potential for cultural evolution has been demonstrated, little is known about mate copying in other Drosophila species. Here, we report the first evidence that Drosophila simulans females also copy the mate choice of their conspecifics. We used the well-established protocol developed for D. melanogaster: a naive, unmated female first observes a conspecific's mate choice between one artificially coloured green and one artificially coloured pink male and is afterwards allowed to choose between two males of the same phenotypes herself. Just as with D. melanogaster, D. simulans females were more likely to choose the same type of male as in the demonstration. This finding underscores the capacity of D. simulans females to engage in rapid social observational learning, a process that may play a significant role in the evolution of reproductive isolation.