The importance of the temporal pattern of syllables and the syllable structure of display calls for individual recognition in the genus Aptenodytes

Aptenodytes penguins have a recognition call consisting of a series of repeated syllables. Play-back experiments were conducted to determine the respective importance of the temporal pattern of syllables and the syllable structure. Two hybrid signals were created by switching the temporal pattern of the familiar call (partner or parent) with that of an alien call, then played back to relevant partners. The hybrid signal with the familiar temporal pattern of syllables and an alien syllable structure induced no response of individual recognition, while the hybrid signal with an alien temporal pattern of syllables and the familiar syllable structure elicited some positive responses.