Two papers by Stephanie King explore the evolution of mother-offspring recognition
Individual vocal signatures play an important role in parent-offspring recognition in many animals. Data from two recent studies led by Branco Weiss fellow Stephanie King have significantly added to our understanding of the vocal mechanisms used by highly social species, such as bottlenose dolphins, in facilitating mother-offspring recognition.
The first study showed that immediately after the birth of their calves, female bottlenose dolphins will produce their signature whistle (i.e. identity signal) at more than five times the usual rate, which allows calves to imprint on their mothers’ signature whistles in the first few weeks of their lives. This facilitates the calf’s recognition of its mother’s call before mother-calf separations occur. The second study investigated the vocal behaviour of mothers as their calves grew older and became more independent. A female dolphin was repeatedly asked to retrieve her 3-month-old calf or to retrieve other objects. The female frequently used her signature whistle to retrieve her calf and rarely produced her whistle when asked to retrieve an object. Thus, as the calf grows older and wanders further from its mother, she will use her signature whistle as a signal that she wants her calf to return to her.
Together these studies highlight the importance of vocal imprinting and maternal signature whistle use in aiding mother-calf reunions in bottlenose dolphins, and also significantly add to a broader understanding of the use of mother-offspring identity signals within the animal kingdom.
Read the papers: