Female acoustic signaling of sexual immaturity depresses male courtship in Drosophila

In an early phase of life, most animals are behaviorally and physiologically not yet able to reproduce but show adaptations specific to a juvenile state. In Drosophila females, sexual maturation after metamorphosis is achieved by acquiring receptivity to male courtship and completing oogenesis, a transition that is under hormonal control and requires coordinates changes in the nervous system. Here, we show that immature females display a transient signaling behavior during the time window of asexuality by flicking their wings in response to and dependent on male courtship stimuli. Immature wing flicks require the activity of Doublesex (Dsx) expressing central brain pC1a neurons that mediate receptivity in mature virgins. Immature wing flicks generate patterned sound pulse trains that differ from other intraspecific acoustic signals, but resemble pulses produced during mature male agonistic interactions. Courting males exposed to immature flicks shorten courtship singing and abstain from copulation attempts, indicating that immature wing flicks serve as an effective rejection signal of asexual females to minimize futile male mating pursuits.