From preferential response to parental calls to sex-specific response to conspecific calls in juvenile zebra finches

In birds, parent-offspring recognition is crucial for directed parental care, and is often based on acoustic cues. The strength and the time of onset of this recognition process depend on ecological factors that constrain parental care. For instance, parent-offspring recognition generally appears earlier in nidifugous than in nidicolous species. We investigated whether fledglings in a nidicolous species, the zebra finch, Taeniopygia guttata, recognize their parents and the fate of this recognition process once the parents had stopped their food provisioning. Zebra finches are gregarious passerines that provide parental care to chicks up to 20 days after fledging. In playback experiments, fledglings preferentially responded to parental calls over other adult calls and thus recognized both their father's and mother's distance calls. However, at 2 months, motivation to respond to parental and other adult calls became sex specific, with sons no longer reacting preferentially to their father's calls, whereas daughters did. This pattern may be linked to the development of sexual traits and mate-searching behaviours. The persistence of parent recognition at the age of pair formation may also be of critical importance during mate choice. (C) 2010 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.