SONG LEARNING AND VOCAL TRADITION IN NUTTALLS WHITE-CROWNED SPARROWS

We investigated song sharing and dispersion of song types in the wild in a colour-marked population of the non-migratory Nuttall's white-cro wned sparrow, Zonotrichia leucophrys nuttalli. The songs of fathers, t heir male progeny (sons), and the neighbours of the sons at recruitmen t sites were analysed spectrographically and compared qualitatively an d quantitatively. To determine whether a son's song more closely match ed that of his father or a neighbour at the site settled, we subjected frequency and temporal characteristics of songs within each father-so n-neighbour triad to multivariate cluster analysis. The songs of 14 of 16 sons clustered with their neighbours' rather than their fathers' s ongs, confirming that song matching of neighbours is an integral compo nent of territory settlement by juveniles. Principal components analys is of frequency and temporal measurements of song within a dialectal a rea show that songs group into neighbourhoods and are non-randomly dis tributed. Multivariate analysis suggests that sons may entrain on freq uency and temporal characteristics of a neighbour's song without match ing phrases or complex syllables. Implications for models of instructi ve versus selective learning are discussed. The timing of closure of t he sensitive phase, the length of the silent interval between the sens ory phase and plastic song stage, and the time to song crystallization remain open questions in song ontogeny. (C) 1998 The Association for the Study of Animal Behaviour.