The Relationship Between Species Specific Song Programs and Individual Learning in Songbirds

Abstract

The species specific song programs, by which the variation of song patterns is limited to predictable features, was analysed in the canaries, greenfinches, and hybrids between the two species. i) Canaries and greenfinches, which could not hear each other, sang different song elements. If we compare single characteristics (such as duration, highest frequency) rather than overall characteristics the elements of different individuals for the same species are very similar. 2) The tour, a rhythmical repetition of identical vocal patterns, is the most typical feature of all songs analysed. These tours have, in all birds, a similar rhytlunical timing. There is a strong correlation between the duration of elements and the interval which follows. 3) Species specific song differences are found in the higher song structure. There is no phrase in the greenfinch. 4) There is no phrase in the songs of hybrids, a feature shared with greenfinches but not canaries. The lengths of tours and the timbre of elements are intermediate with a narrow degree of intra-individual variability. The size of the repertoire is within the range of the parental species. 5) The narrow degree of variability in songs of canaries with different repertoires and the finding that hybrids sing song structures which they are incapable of hearing are hints that the song patterns are genetically programmed and can only be modified by learning within a species specific range.