How Transparency in Butterflies and Moths Helps Ward off Predators
Published:22 Dec.2021    Source:eLife

Transparent wing patches may do more than allow butterflies and moths to hide -- they may also warn predators to leave them alone, suggests a study published today in eLife. The findings shed new light on how some butterflies and moths that have partially transparent wings have evolved to mimic other species that already had this feature. They also provide new details on the tiny structures that allow light to pass through the wing.

 
Despite their delicate look, butterflies and moths have numerous defences. They may use camouflage or transparent patches on their wings to escape a predator's notice, or they may use bright, contrasting colours to warn predators that they are toxic or otherwise unpalatable. These warning colour patterns are so effective at warding off predators that other butterfly and moth species -- even ones without toxic defences -- evolve to mimic them. While transparency usually allows butterflies and moths to escape predators by blending into their surroundings, some species have evolved both transparent patches and vivid warning colours.