“The scales covering the forewings of this beetle display iridescent colours, due to light interference within the structure of the scales. These scales contain lots of tiny pores, filled with air, with a structure which makes different wavelengths of light reflect more brightly at different angles. A droplet of water on the scales can fill these pores, changing the reflected colour from blue to green.”
– another stunning image! By studying the physics of this colour-changing effect, researchers can understand how they occur and see if there are ways to mimic it in artificial structures.