Deciphering dolphin echolocation - researchers create eerie image of a diver as it may appear in a dolphin's brain
A private dolphin research organization based in Miami sparked a minor sensation last month when it released a controversial image of an underwater diver that was reportedly created using data extracted from the high frequency clicks that dolphins emit when they perform echolocation. If the data used to create the image is proven to be solid, it could reveal what and how certain animals "see" in dark and underwater environments.
Speakdolphin.com is a private project founded by research team leader Jack Kassewitz and his wife Donna Kassewitz. The project had been looking for some time at how dolphins communicate.
Dolphins, in common with porpoises, toothed-wales, bats and even some blind people, produce high-frequency clicks that allows them to navigate even the murkiest waters by interpreting the echoes of the sound waves that bounce off objects near them. This way of "seeing" is known as echolocation or bio sonar. It was first studied in depth by Jacques Cousteau, but there is still much to learn about how this sensory system works.
Part of SpeakDolphin's research involved exposing dolphins to objects not found in nature, such as crosses, flowerpots, etc. According to Kassewitz, the team observed that dolphins not exposed to the echolocation experiments identified objects from recorded dolphin sounds with an astonishingly high level of accuracy. The team started looking for ways to see what exactly was happening within the sound waves of the echolocation signals.
Kassewitz reached out to John Stuart Reid, the English co-inventor of an instrument called the CymaScope, which captures imprints of sonic vibrations on the surface of ultra pure water. Kassewitz started recording the sounds made by the dolphins he was studying and sending them to England for Reid to convert to cymascope images.
When most of us think about how to represent sound visually, we generally think of diagrams of volume-dependent sine waves.
But the Cymascope is based on cymatics, an alternative theory of the way the physics of sound works. A simple example of cymatics can be demonstrated when a surface is covered in a thin coating of particles, paste or liquid. When the surface is vibrated by sound, different patterns emerge in the solution according to the frequencies of the sound and other influences such as the geometry of the surface.
In some circles, the study of this phenomenon is known as an "emerging science." In others, it's dismissed as a "pseudoscience."
According to Reid's web site, Cymatics provides insights into the physics of sound. The "Intro" page says: "If we could see the sounds around us with our eyes we would see myriads of holographic bubbles, each with a kaleidoscopic-like pattern [on] its surface."
Reid's cymascope directs sound onto a thin film of water and camera records cross-sections of the vibration patterns.
"After ten or so images came back, one came back over with right-angled lines in it," Kassewitz told Gizmag. "I called John in England and said: 'John, there are all these straight and right-angled lines in there.' John said: 'There can't be.' I send him these wave files in the blind, so he doesn't know what's there. And what's ironic is that these right-angled lines appeared at a time when we were [recording a dolphin] echolocating on a cube."
Kassewitz said that from there the team decided to run more experiments by recording one of their animals echolocating on a number of different shapes. N1 was a cube, N2 was a cross, N3 was a flowerpot. N4 was a rubber duck, N5 was a human being underwater, and N6 was a human face (still under review). "When I sent John the files I did say one of them has a face on it, because I was actually trying to see how a dolphin might see a face underwater. And that's how we got the image of the diver. The exact image of the diver underwater is what John produced on the Cymascope."
In March 2015, Kassewitz turned to a 3D printing organization to transform the cross section 2D image data into a 3D-printable file. The files were then printed in full color, retaining the initial Cymascope image characteristics.
Kassewitz contacted several consulting scientists, including speech recognition expert Dr John P Kroeker and the renowned neuroscientist Dr VS Ramachandran to review the findings and make suggestions for next steps.
Dr Ramachandran told Gizmag: "If my memory serves me right, I saw the final photo and told Jack I'd have to see what process was used to produce it. He then asked if I was open to new ideas and I told him I was. I think I added that the picture was intriguing but that the process used needs to be reviewed and evaluated by people with expertise in this field. I did not see any of the procedures used to produce the image although I'm sure he would happily have showed it to me. I should add that [Kassewitz] seems perfectly sincere and I have enjoyed reading portions of his popular book."
Studies into cetacean brains do seem to show that the auditory nerves of dolphins are directly linked to the visual cortex. And studies into humans who are blind and use clicking as a form of echolocation show that the visual cortex as well as the audio cortex seems to be lighting up.
Kassewitz says the findings are at first blush and he's open to skepticism. "Skepticism is what science is all about," he says. "But here is where I think where at. I think we know how the Dolphins sends the sounds out. We now know that there is an image coming back. We now know that the biology inside the Dolphin allows them to interpret the image. Now the real question is: 'Can that be translated through the cochlear pathway?'"
Kessewitz says the team is writing up a science paper that will be submitted to a major journal by January 15, 2016. Upon acceptance, it will be presented in La Paz, Mexico, at the XXXIV International Meeting for Marine Mammalogy.
There's no denying that there's a strong new age feel to cymatics. However, it's worth noting that some significant scientific breakthroughs came by researchers who were pursuing pseudosciences. Nikola Tesla, for example, made his contributions to modern electricity supply while on a quest to invent a perpetual motion machine. Whatever happens, it will be interesting to see what happens when Speakdolphin's research is reviewed by experts.
Jack Kassewitz discusses the research in the following video.