Vegetational correlates of variation in the song of Zonotrichia capensis

Summary 1. Geographical variation in the song of Zonotrichia capensis, the Rufous-Collared Sparrow, in northwestern Argentina is discussed. Boundaries between song dialects appear to have been stable for at least 10 years. 2. The pattern of song change previously described on a transect across the Aconquija mountains is shown to be duplicated on similar transects elsewhere in these mountains. The association of song types with features of the environment is supported.