MOUTHSPOTS OF PASSERINE NESTLINGS

Summary Maclean, G. L. & Vernon, C. J. 1977. Mouthspots of passerine nestlings. Ostrich 48:95-98. Among passerine families a pattern of black spots in a yellow mouth occurs universally only in the Sylviidae and the Alaudidae. The conservative configuration of these spots seems to indicate a true relationship between the warblers and the larks, and the possession of these mouthspots therefore usually indicates that a species belongs to one of these two families. Similar but less well defined mouthspots occur in only some species of Malaconotidae, Motacillidae, Campephagidae, Pycnonotidae, Timaliidae and Promeropidae. suggesting a possible sylviid ancestry for at least some of these families.