Australian bag moth Cebysa leucotelus

The bagmoth lifestyle is one of the insect world's most extreme domestic arrangements. Larvae spend their entire lives inside a portable silk-and-debris case, decorating it with fragments of lichen, bark, and plant material for camouflage. The truly astonishing part? Females of many bagmoth species never leave their bags at all — not to pupate, not to mate, not even to lay eggs. Everything happens inside.

Males develop wings and fly in search of mates, extending their abdomen into the female's bag to reproduce. After laying her eggs inside the bag, the female dies within it, and her own body becomes the first shelter for the next generation. It's a remarkable, if claustrophobic, life strategy shared by this Australian and New Zealand species.