Culture in whales and dolphins

Studies of animal culture have not normally included a consideration of cet aceans. However, with several long-term field studies now maturing, this si tuation should change. Animal culture is generally studied by either invest igating transmission mechanisms experimentally, or observing patterns of be havioural variation in wild populations that cannot be explained by either genetic or environmental factors. Taking this second, ethnographic, approac h, there is good evidence for cultural transmission in several cetacean spe cies. However, only the bottlenose dolphin (Tursiops) has been shown experi mentally to possess sophisticated social learning abilities, including voca l and motor imitation; other species have not been studied. There is observ ational evidence for imitation and teaching in killer whales. For cetaceans and other large, wide-ranging animals, excessive reliance on experimental data for evidence of culture is not productive; we favour the ethnographic approach. The complex and stable vocal and behavioural cultures of sympatri c groups of killer whales (Orcinus orca) appear to have no parallel outside humans, and represent an independent evolution of cultural faculties. The wide movements of cetaceans, the greater variability of the marine environm ent over large temporal scales relative to that on land, and the stable mat rilineal social groups of some species are potentially important factors in the evolution of cetacean culture. There have been suggestions of gene-cul ture coevolution in cetaceans, and culture may be implicated in some unusua l behavioural and life-history traits of whales and dolphins. We hope to st imulate discussion and research on culture in these animals.