Variation in ultraviolet reflectance by carotenoid-bearing feathers of tanagers (Thraupini: Emberizinae: Passeriformes)

摘要: Avian visual sensitivity encompasses both the human visible range (400–700 nm) and also near-ultraviolet (UV) wavelengths (320–400 nm) invisible to normal humans. I used reflectance spectrophotometry assess variation in UV for yellow, orange red plumage 67 species of tanager (Passeriformes). Previous chemical studies, my analysis minima, suggest that carotenoids are dominant pigments plumage. Spectra recorded over which birds sensitive (320–700 nm) were invariably bimodal, with a plateau high at longer (> 500 nm) distinct secondary peak (< 400 nm) wavelengths. Within this overall framework, was expressed within well-defined quantitative limits: (1) always lower than corresponding wavelengths; (2) intensity declined steadily below 350 nm; (3) clustered between 350 370 nm. Significant correlations detected various measures total wavebands, but not spectral location reflectance. propose strong absorption band short (∼ 380–550 nm) responsible bimodal spectra vitro is by carotenoid-based colours. The construction bands from different sides same absorbance provides mechanism observed covariation Lack an association locations may result limited band. These patterns colours subject constraints, just as more traditional morphological characters. © 2005 Linnean Society London, Biological Journal Society, 2005, 84, 243–257.