Butterfly wings are made up of Nano micro air layered structures scales, which diffract and interfere causing light waves to spread through the spaces between the structures to produce the vibrant colours on their wings.
Humans can only see red to violet in the light spectrum whereas butterflies see all colours including ultraviolet light.
The specific colours that reflect vary from height and distance between the layers. This way of manipulating light results in the brilliant iridescent colours on a butterfly’s wings.
Butterflies rely on these coloured scales for several reasons. Firstly, for protection (camouflage) from predators and warning patterns that tell the predator the butterfly is bad tasting. Secondly, for thermo regulation and insulation, and finally, for signalling a mate. A female butterfly is attracted to a mate by their ultraviolet patterns on the male wings which plays a significant role in their courtship.
Written by Teresa Hermsen