In order tocontrolthissecondarymetabolismsubstanceeffectively, People have been engaged in the studiesofgossypoland itsstorageorgan-pigment gland for a long time.
Although he cannot definitely rule out a direct effect by the pollution on the birds' metabolismof the yellow pigment, or its incorporation into their feathers, the correlation between a shortage of caterpillars and faded plumage is strong evidence of a link between pollution, diet and bird colour.
Beta carotene is a type of carotenoid, a plant pigment that is a provitamin for vitamin A. During its digestion and metabolism, a percentage is converted to vitamin A, a fat-soluble vitamin that is important for vision, growth and development, and healthy immune and reproductive function.