Wing scale ultrastructure underlying convergent and divergent iridescent colours in mimetic Heliconius butterflies.

ABSTRACT: Iridescence is an optical phenomenon whereby colour changes with the illumination and viewing angle. It can be produced by thin film interference or diffraction. Iridescent optical structures are fairly common in nature, but relatively little is known about their production or evolution. Here we describe the structures responsible for producing blue-green iridescent colour in Heliconius butterflies. Overall the wing scale structures of iridescent and non-iridescent Heliconius species are very similar, both having longitudinal ridges joined by cross-ribs. However, iridescent scales have ridges composed of layered lamellae, which act as multilayer reflectors. Differences in brightness between species can be explained by the extent of overlap of the lamellae and their curvature as well as the

SUBMITTER: Parnell AJ 

PROVIDER: S-EPMC5938584 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature