Tracy Burkhard, E. Raney Sachs, Steve Phelps

Despite the importance of vocalizations in mammalian sociosexual communication, little is known about female preferences for male vocal displays in wild mammals. Here, we characterized female preferences for the advertisement songs of male Alston’s singing mice (Scotinomys teguina). We developed procedures for inducing estrus, using vaginal morphology as a bioindicator. We then broadcasted “high-effort” and “low-effort” songs recorded from wild-caught male mice to virgin female singing mice in a two-choice experiment. Our results indicated that females spent more time investigating speakers playing high-effort songs; surprisingly, this phonotactic response was independent of estrus status. In wild singing mice, acoustic characteristics of high-effort male songs positively correlate with body condition. Our data suggest that females could use acoustic cues to select good mates in good condition, thus providing preliminary support for adaptive mate choice hypotheses. More generally, our results support the hypothesis that elaborate Scotinomys song may have been shaped by female choice.