Mitchell, B.; Abbott, A.; Brown, A.; Skinner, L.; Umarova, E.; Kohlmeier, P.

Mate choice is a critical decision, requiring time and energy to assess potential partners\' genetic quality. Consequently, in many species females have evolved the ability to utilize social information by copying the mate choices of others, usually based on visual cues. However, chemical cues offer advantages, such as not requiring active observation of copulations. Using Drosophila melanogaster, we provide the first demonstration of chemical mate choice copying. Student females selected the same male genotype that a teacher female mated at higher frequently than expected by chance. Chemical mate choice copying requires sensing both male and female cues, which might indicate that that male genotype has been chosen by other females. Our work suggests that females, in the presence of mated females, increase choosiness at the virgin stage, elevating sexual selection on male traits. This study provides novel evidence that exploiting social information is more prevalent in flies than previously assumed.