Gum leaf skeletonizer: The venomous 'Mad Hatterpillar' that wears its old heads like a crown

Name: Gum leaf Skeletoniser (Uraba lugens)

Where it lives: Australia and New Zealand

What it eats: Eucalyptus leaves

Why it's awesome: The caterpillar of the gum leaf skeletonizer moth is a hairy little creature that keeps its old head capsules and stacks them on its head. This macabre adornment has earned it the nickname of the "Mad Hatterpillar," inspired by the character from "Alice's Adventures in Wonderland."

But why undertake this elaborate millinery? One study published in 2016 investigated this question by holding trials involving the caterpillars and their natural predators — spiders and stink bugs. The researchers found that attacks on larvae with a stack of headcases took more than 10 times longer than attacks on larvae that had had their stack removed. They found that the empty head capsules acted as a false target for predators and could also be used to deflect the piercing rostrum of a predator.

Related: Caterpillars evolved their weird chubby little 'prolegs' from ancient crustaceans

Gum leaf skeletonizers are also covered with hollow venomous spines — or hairs — containing histamines that can cause erucism, or caterpillar dermatitis. If these spines pierce human skin, they cause a stinging sensation, itching and a rash. This venom can remain within the spines even after a caterpillar sheds its skin.