The use of whirligig beetles (Gyrinidae) and predaceous diving beetles (Dytiscidae) for stimulating breast growth in East Africa is a unique traditional practice. The beetles are collected by young girls from rivers and pools and held to their nipples where the beetles “bite” in a defensive reaction. Simultaneously the beetles secrete defensive substances which are produced in special glands to discourage possible vertebrate predators. Gyrinids produce, among other substances, norsesquiterpenes. The Dytiscids also possess prothoracic defensive glands, which produce, among other substances, hormone-like steroids. Larvae of antlions (Myrmeleontidae) are similarly used in East Africa.