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Stunning image shows diver through the 'eyes' of a DOLPHIN and reveals animals send images through water to each other
- Scientists produced the blurred outlines of a submerged man
- Recorded sonar signals with underwater microphone and converted them
Extraordinary images conjured from a dolphin's sonar have revealed how the creature 'sees' a human swimmer using echolocation.
Scientists
produced the blurred outlines of a submerged man after recording the
sonar signals with an underwater microphone and converting them into
pictures.
Sophisticated processing was used to transcribe the way sound waves imprint themselves on water and create the images.
Scientists produced the blurred
outlines of a submerged man after recording the sonar signals with an
underwater microphone and converting them into pictures.
A
similar technique was used three years ago to capture a dolphin's
echolocation view of inanimate submerged objects, indicating that
cetaceans really can 'see' with sonar.
Team
leader Jack Kassewitz, from the US-based SpeakDolphin project promoting
communication between humans and dolphins, said: 'This is the first
time we have captured a what-the-dolphin-saw image of a submerged man.
'We
employed a similar technique in 2012 to capture a dolphin's
echolocation picture of a flowerpot and several other submerged plastic
objects but the present research has confirmed that result and so much
more.'
The
research, conducted with the help of British experts, took place at the
Dolphin Discovery Centre in Puerto Aventuras, Mexico.
Underwater swimmer Jim McDonough wore a weight belt and exhaled most of the air in his lungs to overcome his natural buoyancy.
A
decision was taken not to use breathing apparatus that would generate
bubbles which could affect the results of the experiment.
The echo signal was sent via email to a UK scientist who has pioneered new technology called CymaScope that makes sound visible.
The research, conducted with the help
of British experts, took place at the Dolphin Discovery Centre in Puerto
Aventuras, Mexico.
Acoustics
physicist Dr John Stuart Reid, from Keswick, who heads the CymaScope
team, said: 'When I received the recording Jack had told me only that it
might contain an echolocation reflection from someone's face.
'I noticed the file name 'Jim' so I assumed that the image, if it existed within the file, would be that of a man's face.
'I
was somewhat dubious whether this could be achieved because the imaging
we had carried out in 2012 was of simple plastic objects that had no
inherent detail, whereas a face is a highly detailed form.'
He added: 'I listened to the file and heard an interesting structure of clicks.
We
now think it is safe to speculate that dolphins may employ a
'sono-pictorial' form of language, a language of pictures that they
share with each other.
'The
basic principle of the CymaScope instrument is that it transcribes
sonic periodicities to water wavelet periodicities - in other words, the
sound sample is imprinted onto a water membrane.
'The
ability of the CymaScope to capture what-the-dolphin-saw images relates
to the quasi-holographic properties of sound and its relationship with
water.
'When
I injected the click train into the CymaScope, while running the camera
in video mode, I saw a fleeting shape on the water's surface that did
not resemble a face.
'I replayed the video, frame by frame and saw something entirely unexpected, the faint outline of a man.'
Computer processing enhanced and cleaned up the image producing more detail, including the weight belt worn by Mr McDonough.
The
results suggest that dolphins can sense more than the shadow of an
object with their echolocation, and are able to resolve surface
features, said Mr Kassewitz.
The results suggest that dolphins can
sense more than the shadow of an object with their echolocation, and are
able to resolve surface features, said Mr Kassewitz.
He
added: 'The dolphin has had around 50 million years to evolve its
echolocation sense whereas marine biologists have studied the physiology
of cetaceans for only around five decades and I have worked with John
Stuart Reid for barely five years.
Even so, our recent success has left us all speechless.
'We
now think it is safe to speculate that dolphins may employ a
'sono-pictorial' form of language, a language of pictures that they
share with each other.
If that proves to be true an exciting future lies ahead for inter-species communications.'
