A new study has revealed that dolphins have names for each other and call for each other just like humans.
Research conducted by the University of St Andrews in Scotland has found that the marine mammals use a unique whistle to identify each other, the BBC reported.
It was suggested that when the animals respond after they hear their own call played back to them.
According to Dr Vincent Janik, from the university's Sea Mammal Research Unit, dolphins live in this three-dimensional environment, offshore without any kind of landmarks and they need to stay together as a group.
Janik said that these animals live in an environment where they need a very efficient system to stay in touch.
It had been-long suspected that dolphins use distinctive whistles in much the same way that humans use names.
To investigate, researchers recorded a group of wild bottlenose dolphins, capturing each animal's signature sound, after which they played these calls back using underwater speakers.
They found that individuals only responded to their own calls, by sounding their whistle back.
The team believes the dolphins are acting like humans: when they hear their name, they answer.
Janik said most of the time dolphins can't see each other, they can't use smell underwater, which is a very important sense in mammals for recognition, and they also don't tend to hang out in one spot, so they don't have nests or burrows that they return to.
The study is published in the Proceedings of the National Academy of Sciences.