Hamadryas velutina, Velutina Cracker

This butterfly is part of the group commonly known as Crackers, due to the males' ability to produce a sound similar to that of bacon crackling in a pan. They do this by flicking a pair of spiny rods, attached to the top of the abdomen, against bristles on the anal claspers. Only the males produce this sound, but both males and females can detect it. It is thought that this may act to deter rival males from territories or play a role in courtship.