Audio-vocal learning in a non-human mammal: the lesser spear-nosed bat Phyllostomus discolor.

In the course of development, pups of the neotropical bat Phyllostomus discolor seem to adapt their isolation calls to the vocal signature of their mother's directive calls. Under controlled experimental conditions however, audio-vocal learning so far has not been demonstrated in any terrestrial mammal except man. In the present study one group of bat pups was hand-reared in the absence of conspecific vocalizations, whereas an unvarying, digitally stored maternal directive call was repeatedly presented to the juveniles of a second group prior to each feeding. In contrast to the unstimulated controls, the animals of the playback group adapted their isolation call structure to this external acoustic reference signal.