How Voice Pitch Influences Our Choice of Leaders

Vocal signals among animals can carry different types of messages simultaneously. The croaking of a frog or the screech of a monkey conveys information about the animal making the sounds: its motivation, its ability to defend resources, its health, and even its genetic quality. Other animals have evolved to pay attention to this implicit information and adjust their own behavior accordingly, because doing so can increase their own evolutionary fitness. For example, research by two of us (Anderson and Nowicki) shows that in an aggressive encounter between songbirds, the loudness of a bird’s song reliably signals the likelihood that the bird will physically attack its opponent. Both the signaler and the recipient stand to benefit from the information exchange, because both can avoid a potentially costly fight if they are not equally motivated or able to defend whatever is being contested, such as a territory, a prospective mate, or a source of food.