Island and island-like effects on vocal repertoire of singing honeyeaters

In this study of songs of the singing honeyeater, Meliphaga virescens, we e xamined the consequences of isolation on the meme pool of syllables from wh ich songs are constructed. We sampled four populations in Western Australia , two of which were sampled 7 years earlier. One mainland sample area, with a large number of syllable types, is part of a geographically extensive po pulation whereas the other three samples with smaller syllable pools are fr om isolated island or island-like populations. The reduction in size of syl lable repertoires of the more isolated populations may have resulted from f ounder effect. Comparisons over the 7-year period indicated that the popula tion proportions of the syllable ty es did not change, significantly in eit her of the two resampled populations, although the correlation between samp le years was stronger in the mainland population than in that of the island . In the two resampled populations, we found some new syllables, but some t hat were present 7 years earlier were missing. Two new syllables appear to have been derived from ones present in the earlier sample, perhaps represen ting cultural drift. (C) 2001 The Association for the Study of Animal Behav iour.