National Geographic: We already knew that bottlenose dolphins can follow "recipes" in preparing mollusks, help other species in distress, and possibly do math. So it may come as no surprise that the marine mammals also call each other by whistles that act as names.
Past studies have shown that individual dolphins have a unique whistle, called a "signature whistle," that they often use in big group settings, like when several pods of dolphins meet at sea.
The idea that dolphins have a name in the form of a whistle...