 The speed with which they learned the critical ingredients of successful cooperation puts them on par with chimpanzees and bonobos.Schmelz, Duguid, Bohn, and Völter presented two species of captive otters, giant otters ("Pteronura brasiliensis") and Asian small-clawed otters ("Aonyx cinerea"), with the loose-string task.Both species raise young cooperatively and live in small groups.