Sydney, Jun 8 (IANS): Dolphins may be more akin to humans than believed, said a study released on Friday, confirming that the marine mammals use individual "names" to identify friends and rivals among social networks.

While parrots, bats, elephants and primates are also known to make vocal calls, they are very similar to one another. Dolphins, however, are able to retain unique signature whistles.

According to the study led Stephanie King of the University of Western Australia (UWA), no other non-human animal has ever been found to do this, even when forming long-term cooperative partnerships.

"When two groups meet each other they will exchange their signature whistles so that they know who's present," the Evolutionary Biologist told Xinhua new agency.

"They sometimes also copy the signature whistle of another animal when they are not around but we don't know what that means yet."

The study was conducted in the Shark Bay, where researchers collected recordings of 17 male bottlenose dolphins, which are known for their formations of alliances.

From a small research vessel, the scientists observed the dolphins and used underwater microphones to record them. The team was able to determine the "names" or individual vocal label of each male.

"Retaining individual names is more important than sharing calls as it allows dolphins to negotiate a complex social network of cooperative relationships," King said.

"The names help males keep track of their many different relationships; who their friends are, friends' friends are, and who are their competitors."

King said the next step will be to study the males' relationships more closely, in order to develop a further understanding of the political landscape of dolphin alliances in Shark Bay.