The Gum Leaf Skeletoniser moth, a native of Australia, has a very unique trait. They wear they shed heads as hats!
As caterpillars grow, they shed their exoskeletons, since their hard protective covering can’t grow with them. Most insects leave their shells behind, but this caterpillar, affectionately labeled “The Mad Hatterpillar,” takes the heads of its old shells and sticks it on its new head, making a column of old heads, as seen above. It is unknown why the caterpillar does that – possibly to warn birds and lizards of its poisonous spines, but that’s rather unlikely.
(via Bug Girl’s Blog)