The insect order Lepidoptera (butterflies and moths) is named for the scales (Greek lepido) on the wing (pteron), but these mosaic-like tiles actually evolved from the hairs and bristles that occur on most insects.
The scales and hairs on moth bodies, legs and wings serve various purposes. First, as with bumblebees (which forage further north and earlier in the year than other insects), they are thought to offer a thermodynamic advantage - moths mostly fly at night, when conditions are cooler.
Second, when a moth is at rest on a leaf or twig the hairy tufts and crests disrupt the smooth, insect-shaped silhouette that might otherwise give it away to bird predators.
Lastly, they provide colour that both helps with camouflage and warns of a foul taste.
Wondering what's the difference between moths and butterflies?
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