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
Pigment in the arts, permanence and stability are desirable properties. Pigments that are not permanent are called fugitive. Fugitive pigments fade over time, or with exposure to light, while some eventually blacken. Pigments are used for coloring paint, ink, plastic, fabric, cosmetics, food, and other materials. Most pigments used in manufacturing and the visual arts are dry colorants, usually ground into a fine powder. For use in paint, this powder is added to a binder (or vehicle), a relatively neutral or colorless material that suspends the pigment and gives the paint its adhesion. A distinction is usually made between a pigment,