Evolutionary transitions and mechanisms of matte and iridescent plumage coloration in grackles and allies (Icteridae).

ABSTRACT: Iridescent structural colour is found in a wide variety of organisms. In birds, the mechanisms that create these colours are diverse, but all are based on ordered arrays of melanin granules within a keratin substrate in barbules. The feathers of the grackles and allies in the family Icteridae range in appearance from matte black to iridescent. In a phylogenetic analysis of this clade, we identified several evolutionary transitions between these colour states. To describe a possible mechanistic explanation for the lability of plumage coloration, we used spectrometry, transmission electron microscopy and thin-film optical modelling of the feathers of 10 icterid species from five genera, including taxa with matte black or iridescent feathers. In matte black species, melanin was densely packed

SUBMITTER: Shawkey MD 

PROVIDER: S-EPMC1885357 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature