Final Report Summary - BLUELEAF (The adaptive advantages, evolution and development of iridescence in leaves) Iridescence is widespread in both animals and plants. While the physical aspects of iridescence i.e. how structures produce these vivid colours, have been studied since Newton, many of the biological questions about the function and impact of iridescence are only just starting to be asked. By focusing on plants, we have discovered that iridescence can be multifunctional, and can have several biological impacts. First, iridescence generated by leaves can directly enhance photosynthesis. Chloroplasts that are modified such that their highly ordered structure directly interacts with light, absorb light better, particularly under low light conditions. This discovery not only explains why so several deep shade plants have evolved such a mechanism, but the unique combination of a photonic structure and a light-harvesting system in the same material may provide inspiration for artificial solar harvesting technologies.As well as enhancing photosynthesis, we have found that iridescence can also act as a form of camouflage, and may therefore benefit leaves that produce iridescence by deterring herbivores. Exactly how iridescence does this, and to what extent different types of iridescence impact on animal vision is something we are continuing to investigate.
