While Dr. Dolittle-like conversations with animals are still years away, they are more in the realm of reality now since researchers recently announced that a dolphin used a whistle it had been taught meant "sargassum," a brown seaweed familiar to marine mammals This particular whistle, along with others for "scarf" and "rope" (manmade objects that dolphins enjoy playing with), previously were invented by researchers and introduced to the dolphins, with the hope that the dolphins might incorporate the sounds into their own "vocabulary."
It was therefore a happy surprise when one of the dolphins, while swimming in the Caribbean near researcher Denise Herzing, blurted out "sargassum." Now the question is: Did the dolphin really know what it was saying?
The jury is still out.
"The dolphins had been playing with sargassum and with each other," Herzing, who is director of the Wild Dolphin Project, told Discovery News. "However, it should be made clear that the mimic of a sound does not mean that the function of that sound is understood. That comes over time with exposure to how a word is used, and this is a challenge in the wild."
The word match occurred late last summer, when a dolphin pod Herzing has studied for over two decades was playfully swimming around her boat. Herzing was wearing a high tech device called Cetacean Hearing and Telemetry (CHAT), created for her by Thad Starner of the Georgia Institute of Technology. Starner is technical lead on the wearable computer Google Glass.
Herzing said CHAT and related hardware are part of a system "with real-time sound recognition, which allows the humans to know when the dolphins are matching a whistle, real time, and gives us the abilities to respond appropriately in real time."
She added, "We hope to eventually incorporate the dolphins' actual signals in the system, as we illuminate what their natural signals mean and how they are used in the wild."
The latest findings of Herzing, Starner and their team are summarized in the current issue of New Scientist, and will be presented at the 2014 IEEE International Conference on Acoustics, Speech and Signal Processing in Florence, Italy, this May.
Justin Gregg is a research associate with the Dolphin Communication Project and is author of the book "Are Dolphins Really Smart? The Mammal Behind the Myth." Gregg has been following Herzing's work for some time.
He noted that "dolphins show a clear, rather extraordinary desire to interact socially with human beings," even though it's been challenging to communicate with them using visual and audible signals.
"Contrast, if you will, the communication board used by Kanzi the bonobo, which contains hundreds of symbols that he uses to represent objects, actions and abstract concepts, with the communication devices used by dolphins, who have only ever used/produced a handful of symbols (whistles or lexigrams) to represent objects," Gregg said.
Biostatician Michael Coen of the University of Wisconsin-Madison, through other work on white-cheeked gibbons, has uncovered nearly 30 basic components of gibbon calls.
Dolphins are extremely intelligent, large-brained and social animals, so Gregg suspects that the difficulty of conducting experiments in an aquatic environment has slowed progress on deciphering dolphin "speak" versus that of non-human primates.
CHAT continues to improve, though, and with it comes a heightened chance of holding conversations with dolphins, or at least understanding them better. "Sargassum" might be one small whistle for dolphins, and one giant leap for interspecies communication.
"It's a very exciting time, but it will take time and a lot of data to really look at what is going on," Herzing said. "CHAT is potentially an interface to see if we could bridge the gap between species by empowering them with tools to communicate in detail, and it may also be a tool to help us to understand parts of the dolphin mind and their cognitive abilities."