For years scientists have known that killer whales "speak" in dialects specific to their social group. They use a series of clicks, whistles and pulses to communicate with one another, a behavior which is learned.
From one killer whale clan to another, the difference in dialect can be significant. The Smithsonian reported that in some cases, the difference can be likened to that of the difference between Greek and Russian.
So it wasn't a complete surprise when University of San Diego graduate student Whitney Musser and Hubbs-SeaWorld Research Institute senior research scientist Dr. Ann Bowles found that killer whales sounded a lot like the bottle nosed dolphins they were socialized with. The data was collected from two SeaWorld Parks and a Six Flags Discovery Kingdom park.
"Killer whales are adept social learners. They learn easily from each other. This is culture, and culture is a basis of their lives," Hal Whitehead, researcher at Dalhousie University, told TreeHugger. "One isolated killer whale learned seal calls."
The whales observed by Musser and Bowles were even able to mimic a sequence of sounds that trainers had taught the dolphins before they were put in with the killer whales. This suggests that their brains have high levels of neural plasticity.
Musser and Bowles also found that the killer whales had a bit of an accent. While they were able to reproduce four times as many whistles as a control group of killer whales, their whistles were at lower rates than their dolphin friends.
"It is yet another confirmation that learning is central to how killer whales acquire their vocal repertoire, and further confirms the status of the cetaceans as one of the few groups of mammals to have evolved true vocal learning," said Dr. Luke Rendell, a lecturer in biology at the University of St. Andrews.
The study was held in conditions that are increasingly controversial as evidence of whale intelligence and social complexity grows: the whales and dolphins were captive. Killer whales have been shown to suffer when trapped in small pools of water and the Dodo recently reported that free whales live more than 4 times longer than whales in captivity. While studies like Musser and Bowles' add valuable understanding to these mysterious creatures, the question remains: should humans be experimenting on animals in these circumstances?