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
Green Is the Colour song was a regular part of the band's shows from early 1969 through 1970, then less common in 1971. It was played for the last time during their short tour of Japan and Australia in August 1971. The song was later played by Nick Mason's Saucerful of Secrets. with: Green Is the Colour "Green Is the Colour" is a track on Pink Floyd's 1969 "More". It was composed and written by Roger Waters and sung by David Gilmour. A tin whistle is heard in the song, played by drummer Nick Mason's then-wife Lindy. A live version of the song was