Carotenoid pigments in male American goldfinches: What is the optimal biochemical strategy for becoming colourful?

Agriculture & Biology

• carotenoids 68%
• pigments 61%
• zeaxanthin 55%
• molting 43%
• lutein 37%
• feathers 35%
• birds 35%
• blood 33%
• color 27%
• Carduelis 17%
• xanthophylls 15%
• canaries 15%
• wild birds 13%
• plumage 12%
• biologists 12%
• diet 11%
• seasonal variation 9%
• gender 7%
• animals 4%

Earth & Environmental Sciences

• carotenoid 100%
• pigment 77%
• bird 58%
• blood 46%
• feather 42%
• diet 20%
• plumage 17%
• molt 15%
• plasma 8%
• animal 7%