If you’re even slightly familiar with Lewis Carroll’s novels, the mad hatterpillar (or gum leaf skeletoniser) won’t need much of an explanation. Adult skeletonisers are quite unassuming looking moths, but the larvae owe their nickname to the tower of head capsules retained from each instar following ecdysis. The role these hats of heads play isn’t clear, though a studyby behavioural ecologist Petah Low et al. suggests a defensive function. They’re wrong.