Courtship song's role during female mate choice in the field cricket Teleogryllus oceanicus

Sexual signals consist of multiple components, each of which can contribute to mating decisions. Male field crickets use 2 acoustic signals in the context of mating: a calling song that attracts females from a distance and a courtship song that follows once a female makes physical contact with a male. The function of courtship is unclear because females have already chosen and approached a particular male based on his calling song. Using the field cricket Teleogryllus oceanicus, we tested whether females evaluate the attractiveness of males based on their courtship song irrespective of other male qualities. In a tournament-style assay, females chose males based on elements of their courtship song and preferred males with longer courtship songs that had a higher duty cycle (more sound per unit time). Courtship song was also highly repeatable not only within a bout but also between days in the presence of different females. Additionally, we manipulated the attractiveness of males to females by surgically silencing males and broadcasting playbacks of artificially constructed courtship songs. When we broadcast a preferred song model during courtship by previously nonpreferred males, females showed greater attraction, and vice versa. Courtship song may be particularly important in systems with satellite males that do not produce long-range signals because it gives females their only opportunity to evaluate potential mates.