Biologists from the University of St Andrews in Scotland studying the vocal signatures of the mammals sat they found dolphins can mimic the distinct whistles of their closest companions and offspring as a way of tracking them
It has been known dolphins develop their own individual whistle, and the new study suggests they can also mimic the calls of those dolphins they want to stay close to.
The St. Andrews researchers, working with U.S. scientists in Florida to study dolphins in the state's Sarasota Bay, found the mimicking was only present in mothers and their offspring and in adult males who copied calls of those they had long-term associations with.
"Interestingly, this mimicking only occurs in animals who have strong social bonds," St. Andrews researcher Stephanie King told the BBC.
"It also only occurs when they are separated from each other, and this supports the idea that they want to reunite with the other animals."
Dolphin mimicking may offer an insight into the way complex language structures evolve, the researchers said.
"It is something we see in ourselves, but not in other animals," King said.
"This could give us a real insight into how certain traits in language and communication have evolved."