Some millipedes defend themselves with hydrogen cyanide

Deep in the forests of North America, the flat-backed millipede Apheloria virginiensis uses a sophisticated chemical laboratory to ward off predators. When a bird or lizard attempts to eat one, the millipede does not bite or sting. Instead, it releases a defensive secretion that smells remarkably like bitter almonds. This pleasant scent is actually a warning sign of a much more dangerous substance.