Carotenoid-based plumage coloration has been shown to be dependent both on pigment content and feather structure. Against this background, we predict a relationship between feather pigment content and plumage hue. Furthermore, given the susceptibility of chroma to developmental perturbation of feather structure, we predict body condition to be related to chroma. We tested these predictions in the great tit, Parus major. Carotenoid content in yellow breast feathers was analysed by high-performance liquid chromatography (HPLC). Lutein was the main carotenoid contained in great tit feathers, followed by zeaxanthin. The hue of the feathers was accurately predicted from their lutein concentration, and chroma was predicted from the body condition value. Our data suggest that plumage coloration in the great tit could independently provide information on the ability of the signaller to collect carotenoids (via hue) and body condition (via chroma). Published results both from the great tit and other species support this view

CGL2006-07481 project to JCS, JJN and JG from Ministerio de Ciencia y Tecnología and grants FPI2000-0014 to IR (CIRIT, Generalitat de Catalunya) and FP2000-6439 to JQ (Ministerio de Ciencia y Tecnología), funded this work.

Peer reviewed