Dolphins call each other by name!

The Guardian Online

Bottlenose dolphins have distinct “names” that they use to identify individuals in their social group, according to a study by scientists who followed groups of the animals off the east coast of Scotland.
The names are composed of whistles which they use throughout their lives to broadcast their locations to other dolphins they meet at sea.
Dolphins make a lot of vocalisations to communicate with each other, including echolocation clicks, whistles to attract other animals to food locations and other noises to indicate how aggressive or friendly they feel.
The signature whistles are most often used by dolphins when they are travelling in groups and want to let their companions know where they are.
“Other contexts are particularly when groups meet at sea, they exchange information about who is present before the groups join, almost like a greeting,” said Vincent Janik, a biologist at St Andrews University, who led the research.
His research team wanted to know how far dolphins were using these skills to identify each other and themselves.
They watched a population of around 150-180 dolphins living off the east coast of Scotland, following groups of between two and 20 dolphins at once, initially identifying and recording signature whistles and then playing these whistles back to the entire group.
“The way you see who is responding is to listen for the signature whistle to see if the animal produces its own whistle back to you when you play its whistle,” said Janik.
The results, published in the Proceedings of the National Academy of Sciences, showed that dolphins responded to their own signature whistles whenever they heard them by whistling their own “name” back, but would ignore the whistles of others