Melbourne: They are celebrated for their playful natures, and now dolphins in the wild are teaching themselves how to "walk" with their tails along the surface of water, say biologists.
A team at the Whale and Dolphin Conservation Society in Australia claims that the mammals are developing the skill "just for fun".
Dolphin tail-walking has no known practical function and has been likened to dancing in humans.
Team leader Dr Mike Bossley, who has observed Adelaide`s Port River dolphins for the past 24 years, said he had documented spectacular tail walking in two adult female dolphins, known as Billie and Wave.
According to him, the spread of tail walking appeared to be motivated by "fun", but it was also linked to a serious and fascinating cultural aspect previously unseen in species, `The Daily Telegraph` online reported.
He said: "Culture in the wider sense of the term, defined as `learned behaviour characteristic of a community`, is now frequently on show in the Port River. This cultural behaviour is of great significance for conservation.
"Cultural behaviours in animals have been identified in several species, particularly chimpanzees. However, most if not all the cultural behaviours described to-date have been of a utilitarian nature, mainly to do with obtaining food.
"A well-known chimpanzee example is using a twig to extract termites from a nest in the Gombe Stream reserve. The only dolphin example seen up to now is in Shark Bay, West Australia, where a small group of dolphins habitually carry a sponge on the end of their jaw while fishing.
"As far as we are aware, tail walking has no practical function and is performed just for fun - akin to human dancing or gymnastics. As such it represents an important example of behavioural similarities between humans and dolphins."