March 8, 2013
Dolphins Give Each Other Names Through Mimicry
Michael Harper for redOrbit.com — Your Universe Online
Dolphins are one of the more majestic creatures in the animal kingdom. Their grace under water and their humanesque behaviors have led many to believe that these underwater animals can even have healing and soothing effects on the ill. And continued research is finding even more new and interesting things about these intelligent mammals.
Now, one Sarasota marine biologist says he believes these animals use their sounds to assign one another names, making it easier for them to communicate underwater.
Dr. Randall Wells with the Sarasota Dolphin Research Program has discovered that dolphins are able to mimic one another´s speech patterns to get the attention of their peers. His research on the matter was published last month in the Proceedings of the Royal Society B.
"These whistles actually turned out to be names. They're abstract names, which is unheard of in the animal kingdom beyond people," said Wells in an interview with WFLA-TV in Tampa, Florida.
Dr. Wells worked with other scientists from the University of St. Andrews in Scotland, the Chicago Zoological Society, the Woods Hole Oceanographic Institute (WHOI) in Massachusetts and marine biologists with the Walt Disney World Resort. Together, these scientists focused on a behavior they call “vocal copying,” or the means by which dolphins learn to mimic one another´s speech patterns.
"Each dolphin produces its own unique signature whistle that describes its individual identity," explained the scientists in a statement. “The new study suggests that in fact dolphins are mimicking those they are close to and want to see again."
To conduct this study, the scientists began collecting some previously-recorded audio samples of dolphins “talking” to one another.
The scientists collected and replayed recordings of about 250 bottle nose dolphins in the wild living around Sarasota bay. After listening to the audio samples, the researchers (and five volunteers) began to notice a pattern. When two or more dolphins spent enough time together to become familiar with one another, they began picking up on some of the speech patterns of their peers. When the dolphins weren´t together in a group, they´d continue mimicking the speech patterns of their peers. This kind of mimicry was not found in dolphins that had only a casual encounters with another dolphin; they only copied those with whom they were quite familiar.
"The fact that animals are producing whistle copies when they are separated from a close associate supports the idea that dolphins copy another animal's signature whistle when they want to reunite with that specific individual," explained Stephanie King of St. Andrews.
Though King and crew did notice this copying behavior, they found that it was used infrequently, possibly to avoid confusion amongst one another.
The researchers now plan to begin playing dolphins´ whistles back to them to observe how they behave when hearing their own voice.
For now, Dr. Wells is excited to have discovered this behavior and says it comes in handy when the animals are swimming in dirty waters, such as those found in the Gulf of Mexico.
"These animals are living in a murky, estuary environment. They have to maintain group cohesion and stay in contact with one another and coordinate their activities- how do you do that when you can't see one another?”