A cooperatively breeding mouse shows flexible use of its vocal repertoire according to social context

Mice exchange information using chemical, visual and acoustic signals. Long ignored, mouse ultrasonic communication is now considered to be an important aspect of their social life, transferring information such as individual identity or stress levels. However, whether and how mice modulate their acoustic communications is largely unknown. Here we show that a wild mouse species with a complex social system controls its vocal production both qualitatively and quantitatively, depending on social context. We found that the African striped mouse Rhabdomys pumilio, a cooperatively breeding species, has a vocal repertoire consisting of seven call types, which it uses differently depending on whether the individuals encounter another mouse that is familiar, unfamiliar, of the same or different sex. Familiar individuals, whether of the same or different sex, vocalize more than two unfamiliar same-sex individuals. The greatest diversity of vocalisations is recorded when a female and a male first encounter, suggesting that certain calls are reserved for courtship. Our results highlight that familiar mice alternate their vocalisations (turn-taking) while unfamiliar individuals tend to overlap one another. These observations suggest that African striped mice control the production and temporal dynamics of their vocalisations, addressing targeted information to specific receivers via the acoustic channel.