The wings of wasps and flies contain stunning, built-in reflective patterns that can only be seen against a black background. Called wing interference patterns (WIP), they are the result of membranes that are thicker in some parts and thinner in others, which allows for the reflection of different colors without any pigments. So far, we think that WIPs may serve as signals between the insects. Entomologists and taxonomists can also rejoice, because WIPs are species-specific —a useful piece of knowledge that has already led to the discovery of several new species within those we already (thought we) knew.
Read the paper (here)
(Check out Ed Yong’s Not Exactly Rocket Science for more.)