Female song elicits increased vocal display effort in both sexes of Alston's singing mouse

Acoustic displays are conspicuous behaviours common across diverse animal taxa. They have long been studied in behavioural ecology, evolutionary biology and neuroscience. Most of these investigations, however, have focused on male display. For species in which both sexes display, correcting this bias will lead to a fuller understanding of the evolution and function of these behaviours. In this study, we investigated the role of vocal advertisement display in female Alston's singing mice, Scotinomys teguina. Singing mice are small muroid rodents of the family Cricetidae, native to high=altitude cloud forests of Central America. Females and males both produce elaborate advertisement songs, known in males to be used in mate attraction and intrasexual competition. Prior studies have largely focused on male behaviour, although we recently found that both sexes dramatically increase their rate of singing and song duration in response to playback of conspecific male song. Here, we tested how mice of both sexes adjust their song effort in response to female song playback. Our results show that, like male song, female song elicits robust increases in song effort from both female and male mice. This study reveals additional social contexts that promote high song effort in this species, while raising further questions about the role of song in communication within and between the sexes.