Insect Wings: Origins and the Physics of Their Beauty
Wings have certainly contributed to the success of many groups of insects. Their origin, however, remains a matter of considerable controversy. Suggestions have been made that they are a novel outgrowth of the body wall, or that they are an extension of an ancestral leg segment, or even that they have a dual origin with components coming from both the body wall and leg segment. I will discuss new data from the functional analysis of leg gap genes in the crustacean, Parhyale, that suggests that both the body wall and leg segment theories are correct, but not because of dual origin, but rather because of the sequential steps in evolution which have occurred to fashion insect wings. I will also discuss later evolutionary modifications that have given color to wings, and how some of these colors are formed via nanostructures controlling light refraction, as opposed to pigments, and our recent work on the cellular and genetic mechanisms responsible for generating these nanostructures.