Blue Morpho Butterfly

The Blue Morpho is one of the most recognisable insects on the planet, and for good reason. That electric blue is almost impossible to photograph accurately — cameras always make it either too saturated or too flat.

What most people never see is the underside. Flip those wings over and you find a dull brown surface covered in eyespots, a completely different creature. It is the ultimate disguise. Wings open: a flash of iridescent blue that confuses predators. Wings closed: invisible against the forest floor.

This one was photographed in a Costa Rican cloud forest at around 1,400m elevation, resting on a rotting fig. The blue you see here is not pigment. Like the stag beetle, it is structural colour — nanoscale ridges on each wing scale that interfere with light.