Annual Plant Reviews, Volume 14 It is difficult to over-state the importance of plant pigments in biology. Chlorophylls are arguably the most important organic compounds on earth, as they are required for photosynthesis. Carotenoids are also necessary for the survival of both plants and mammals, through their roles in photosynthesis and nutrition, respectively. The other plant pigment groups, such as flavonoids and betalains, have important roles in both the biology of plants and the organisms...