Biological pigment symbiosis Trididemnum solidum, their colors are different depending on the light regime in which they live. The colonies that are exposed to full sunlight are heavily calcified, thicker, and are white. In contrast the colonies that live in shaded areas have more phycoerythrin (pigment that absorbs green) in comparison to phycocyanin (pigment that absorbs red), thinner, and are purple. The purple color in the shaded colonies are mainly due to the phycobilin pigment of the algae, meaning the variation of exposure in light changes the colors of these colonies. Aposematism is the warning coloration to signal potential predators to stay
Budgerigar colour genetics Budgerigar colour genetics The science of budgerigar colour genetics deals with the heredity of mutations which cause colour variation in the feathers of the species known scientifically as "Melopsittacus undulatus". Birds of this species are commonly known by the terms 'budgerigar', or informally just 'budgie'. The wildtype (natural-coloured or wild occurring) budgerigar's colour is called Lightgreen. The feathers of most parrot species, including budgerigars, contain both a black type of "melanin" named "eumelanin" along with a basic yellow pigment named psittacofulvin (psittacin for short). Some other parrot species produces a third pigment named advanced-psittacin which enables colour & tones ranging