Song learning by chaffinches: how accurate, and from where?

Geographical variation in song is a common feature of populations of territorial songbirds. However, the factors responsible for the levels and patterns of variation have not been examined in detail. We measured geographical variation of songs in chaffinches, Fringilla coelebs, in samples from five locations in Scotland, U.K. We found substantial variation in the level of song sharing between locations. It was highest in isolated island areas and in a recently populated area. By comparing our data with a spatial simulation model designed to mimic the different areas, we calculated estimates of cultural mutation that ranged between 0.001 and 0.03, with a maximum possible value of 0.05, and found that chaffinches had a significant preference for learning songs not from immediate neighbours, but from males about 500 m away. We discuss the implications of these findings for the process and function of cultural transmission of song in the chaffinch. (C) 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour.