Meet the snake-mimicking butterfly (Dynastor darius). While this slick master of disguise may show off impeccable imitation skills, prior to taking on this serpentine appearance it was simply a furry, nondescript caterpillar, and it looked pretty much how you would expect any old caterpillar to look.
Photo Credit: LuciRamms. A caterpillar-looking caterpillar munching on a leaf; no surprises to see here.
To enter into the pupal stage, D. darius must form a chrysalis to kickstart its metamorphosis into a snake-mime. The protective case in which the butterfly larva liquefies itself does bear a strong resemblance to the carnivorous reptiles, much like the galled face of a Metapod.
The pods hang from leaves in the forests of Trinidad for up to 13 days. While the insect changeling is immobile this sly animal trickery can ward off potential predators, such as birds, fooling them into thinking that the unmoving pod is the head of a potential predator.
Photo Credit: Andreas Kay via Flickr