ABSTRACT
The appearance of structural color in nature dates back to the Cambrian epoch [Kobluk and Mapes 1989]. While widespread in the animal kingdom [Kinoshita 2008, Lee 2007], structural color in plants was until recently thought to occur only very rarely. With a vast literature on the use of photonics structures in butterflies, beetles, weevils, birds, and many other animal species, reports of color-generating structural elements in plants were limited to the iridescence in Selaginella, fern leaves, and several fruits, Rayleigh scattering in blue spruce and chalk dudleya, and enhanced ultraviolet (UV) reflection in Edelweiss [Lee 2007, Vigneron et al. 2005].
