Dolphins May Call One Another by Name
Recent research suggests that dolphins may have the ability to call each other - if not by name, then by whistle.
The notion that dolphins have name-like whistles has been scientifically documented for about 50 years, according to Science. Subsequent research found that dolphins did mimic each other's calls and that dolphins learn their name-like whistles from their mothers. However, this recent study, conducted by researchers at the University of Saint Andrews in the United Kingdom and the Walt Disney Resort in the United States, is the first to discover that dolphins' whistles can be used to call one another. This study would mean that dolphins are the only other animal besides humans that are documented to do so.
It is difficult to study dolphins' signature whistles, because they are done in sometimes murky water, making it difficult to know who made a sound first. In order to study this process, research studied dolphins in two ways. They listened to acoustic data that had been obtained over decades by the Sarasota Dolphin Research Program, according to Wired. In order to obtain the acoustic data, the Florida-based research program, captures dolphins in a net. The dolphins cannot see one another, but they can hear one another, so they can continue to "talk" to one another.
In the recent study, researchers found that dolphins were copying their friends' signature whistles. They found that the whistles were only performed in a friendly context, like between mother and calf, or close male friends. Often, researchers found that dolphins added some trills to the whistle, as if they were communicating additional information. They did not find that the whistle was used in aggressive or deceptive contexts, as some researchers had previously hypothesized.
Some experts are not convinced by the study, however. Robert Barton, from Durham University in the United Kingdom, has previously been uncomfortable with calling dolphins' whistles names. He pointed out that the dolphins called one another frequently. While the authors of the study suggest that the frequency is because dolphins use the name for select companions, Barton believes that it could just mean that there is limited importance attached to the whistles.