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
Labrador Retriever coat colour genetics characterized in mice and other mammals. Initial genetic studies of coat colour in dogs published in the 1950s concluded that there were two main genes involved, one distinguishing blacks from browns, and the other distinguishing blacks from reds and yellows. A 1977 study using crosses within a population of purebred Labradors showed the involvement of two specific genes in production of the three main coat colours of Labradors and described the underlying genetics of these colour varieties. The three recognised colours of Labrador Retrievers result from differences in two genetic loci that affect pigment expression. The first of these affects