This moth has a secret! To see it, move your cursor over the image!

This Polyphemus Moth (Antheraea polyphemus) uses a defense technique that is common among insect - a flash pattern! When it is sitting on a tree trunk, it blends in almost perfectly, it is cryptic. But when it thinks the game is up and a bird sees it, it flashes the owl-like eyespots on its hind wings. Birds aren't very smart so the jump back. This gives the moth a chance to fly away, or drop to the ground where it might again disappear among the dead leaves. By the way, it is named after a mythological creature, a Cyclops named Polyphemus!
(Thanks to Brian for the set up!)