Abstrakt
Carotenoids belong to biochemicals essential in the animal diet. This is due to their indispensability in several life-preserving physiological processes.
In many species, however, carotenoids serve also as the main pigments colouring various ornamental structures engaged in the mate choice. Although intensively studied by biologists, the evolutionary causes for sexual selection mediated by carotenoid-based ornaments remain unclear.
Much of the evidence currently available indicates that carotenoids may signalise individual's health status. A number of different hypotheses has been proposed to explain this phenomenon.
One of the most widely accepted hypotheses connects ornamental health signalling via carotenoids with their antioxidative function in the animal bodies. However, most recent findings cast some doubts on this explanation.
Novel alternative hypotheses based on indirect signalling and the handicap principle appear to provide a possible key to resolve the riddle.