London - Dolphins are known for being very friendly creatures – so much so, it has emerged, they even have names for each other.
The animals have specific signature whistles for their companions and call out to each other just like humans do.
Biologists recorded the whistles of wild bottlenose dolphins off the east coast of Scotland.
They then monitored the animals as they dolphins’ own signature whistle, the whistles of familiar dolphins from the same population and unfamiliar ones from a different group, using microphones dangling off a boat.
The dolphins responded to their “own” whistles by calling back – and did not respond to others, much like human names, said Dr Stephanie King and Dr Vincent Janik of St Andrews University in Fife.
They said naming is one of the defining features of human language and dolphins are the only animals apart from humans that do this to give themselves a unique “identity signal” the study, in Proceedings of the National Academy of Sciences, found.
Dolphin whistles, high pitched “eeeee” sounds, can be detected up to 12.4 miles (about 20km) away and are very different from each other, using “a variety of modulation patterns going up or down, like a tune”, Dr Janik said.
They are believed to have arisen as a result of dolphins’ constantly changing social groups and poor under water vision.
“So they have developed this sophisticated sound system to keep in touch otherwise they could get lost from each other for good,” said Dr Janik. - Daily Mail