An update on the honesty of melanin-based color signals in birds.

摘要: The control mechanisms and information content of melanin-based color signals in birds have generated much recent interest controversy among evolutionary biologists. Initial experimental studies on this topic manipulated coarse metrics an individual's condition (i.e. food intake, disease state) failed to detect significant condition-dependence melanin ornament expression. However, three new lines research appear profitable target specific factors associated with the production pigments. These include role (i) metals, (ii) amino acids, (iii) testosterone social interactions shaping extent intensity melanin-colored plumage patches. Here, I review evidence for these honesty-reinforcing mechanisms.