Olfactory imprinting as a mechanism for nest odour recognition in zebra finches

Olfactory communication is widespread across the animal kingdom but until recently was believed to be unimportant in songbirds. However, recent studies of zebra finches, Taeniopygia guttata, have found that fledglings are capable of recognizing their own nest based on olfactory cues alone. This raises the important question of whether this knowledge is learned or innate. To discriminate between these two hypotheses, we experimentally fostered single eggs into foreign, unrelated broods, and subsequently tested the odour preferences of the respective fledglings. In contrast to a previous study in which individuals were fostered as chicks, we found a strong preference for the host nest odour. This suggests that olfactory imprinting occurs and is based on a familial template learnt within a narrow time window around hatching.