According to a recent study by the Indian Institute of Science published in the journal, Proceedings of the National Academy of Sciences, Bottlenose Dolphins actually call each other by name…well, sort of. “Bottlenose dolphins develop their own unique identity signal, the signature whistle. This whistle encodes individual identity independently of voice features. The copying of signature whistles may therefore allow animals to label or address one another.” As part of the study, researchers would choose a particular dolphin and play his/her unique whistle, and that dolphin would actually call back in response to hearing his/her “name”. When the dolphins heard the whistle “name” of another dolphin, they did not respond. This suggests that Bottlenose Dolphins actually learn their identity signal (“name”), and use their names as a way to label and identify one another. In fact, Bottlenose Dolphins are already known for forming cliques (Natural News), so this idea of identity signals explains how they are able to differentiate one dolphin from another in order to create their circle of friends. Bottlenose Dolphins appear to be highly advanced in communication, especially for a nonhuman species, so I have a feeling scientists will continue to study them further after this incredible discovery.