The Mad Hatterpillar Wears Discarded Heads As Hats
Bizarre looking insects can be found everywhere in the world, but they are especially numerous in Australia. You have likely never heard of a mad hatterpillar, which is surprising since they are the only insects that wear their old discarded heads as hats. That sentence sounds strange. To put it more clearly, this caterpillar sheds its exoskeleton as it grows, which is normal. What is not normal is to keep the heads that they have already shed as hats. Now you can understand why these caterpillars are referred to as the mad hatterpillars. These caterpillars are formally known as Uraba lugens, and they are the larvae of Gum Leaf Skeletoniser moths.
Like all caterpillars, the mad hatterpillar eats food at a near constant rate in order to one day become a healthy and fully formed moth or butterfly. These caterpillars feed on eucalyptus until their bodies grow too large for their exoskeletons. Eventually these exoskeletons are discarded, mostly discarded anyway. Unlike most caterpillars, the mad hatterpillar has a unique sense of style as they like to keep their old heads. The old heads sit right on top of their current heads. This makes the caterpillar appear as if it possesses several identical heads. As you can already guess, their hats become taller as they grow. Eventually their heads form a stack that resembles a totem pole.
You may be wondering why these caterpillars keep their old discarded heads as hats. Well researchers are curious as well. In fact researchers have been speculating as to why these caterpillars retain their discarded heads since at least 1880. This is the year that an academic study describing this caterpillar was published. The study’s author speculated that the heads may serve to fool predators into thinking that the discarded heads were a part of the caterpillars functioning body. But the author ultimately disregarded this bit of speculation and admitted that he “could not imagine” why keeping the heads were necessary for the organism’s survival.
Have you ever heard of an insect using its old exoskeleton for any purpose?