Male-male interactions shape mate selection in .

Males of many species have evolved behavioral traits to both attract females and repel rivals. Here, we explore mate selection in from both the male and female perspective to shed light on how these key components of sexual selection - female choice and male-male competition - work in concert to guide reproductive strategies. We find that male flies fend off competing suitors by interleaving their courtship of a female with aggressive wing flicks, which both repel competitors and generate a 'song' that obscures the female's auditory perception of other potential mates. Two higher-order circuit nodes - P1a and pC1x neurons - are coordinately recruited to allow males to flexibly interleave these agonistic actions with courtship displays, assuring they persistently pursue females until their rival falters. Together, our results suggest that female mating decisions are shaped by male-male interactions, underscoring how a male's ability to subvert his rivals is central to his reproductive success.