Language is one of the defining characteristics of human intelligence. We know that other animals communicate with each other, sometimes richly, but we like to think that the complexity of our social interactions is one of the things that makes our species unique. New research suggests that one of the other smartest species on the planet, the dolphins, may have language skills that are a lot more complex than we thought, as they've demonstrated their ability to call each other by individual names.

According to researchers working with scientists at the Walt Disney World Resort in Florida, this finding makes dolphins the only other living beings on the planet other than humans to assign such specific monikers to known family members and associates. Researcher Stephanie King, of the University of St. Andrews Sea Mammal Research Unit, said, "animals produced copies when they were separated from a close associate and this supports our belief that dolphins copy another animal's signature whistle when they want to reunite with that specific individual." The scientists believe the name assignments are limited to particular groups. King continues, "interestingly, signature whistle copying was only found in pairs of animals composed of mothers and their calves or adult males who form long-term alliances with one another."

Dolphins are widely accepted as one of the most intelligence species on the planet, but it's difficult to look at this kind of research without wondering if we're simply not yet able to understand similarly complex dynamics in other animal species.