Above the water, they make a sound like bending cookies. Beneath the ice, they sound like chippers, chattering robots. Either way, Antarctica’s Waddle Seal should have no trouble finding work in the future Star Wars Project.
“The calls of the waddle seal make an almost unbelievable, other worldwide sound under the ice,” said Paul Czico, a visiting professor at the University of Reg Reagan and lead author of the new study describing the strange seal sounds. “It really feels like you’re in the middle of a space war Star Wars, Laser beams and all. “
C: You have to be an alien (or a droid) to hear them; All those scientific sounds are completely inaudible to the human ear.
Two years after Zico and his companions heard the Waddell seal, they were able to find the voices of another equestrianLeptonichots vadelili) With a special hydrophone (underwater microphone), installed in 2017 at McMurdo Sound in Antarctica.
Before researchers began recording, scientists knew about the 34 seal calls that make up the human ear. Now, the team’s research – published online on December 18th The Journal of the Acoustic Society of America – Nine new types of ultrasonic coils have been added to the seal repository. Those sounds include trills, whistles, and alien-sounding chips, sometimes composed of multiple harmonious tones.
Researchers have noted that humans hear in the sonic range of 20 to 20,000 Hz (or 20 kHz). Most of the newly emitted seal sounds exceeded 21 kHz, some continuously increased to 30 kHz.
(McMurdo Oceanographic Observatory)
Above: Visual representation (spectrogram) of one of the nine ultrasonic call types. The U-shaped features in the upper part of the plot are part of the call type U101.
A high-level sprinkler reached an annoying 49.8 kHz level, and when the seal harmonizes multiple tones, the resulting noise could exceed 200 kHz, the team wrote. (It’s better than a range of hearing cats, dogs and some bats.)
What about all these high-frequency messages? Researchers are not sure; So far, scientists have never been able to detect sound in seals (or any other winged mammals, such as sea lions or vultures).
A diver observes a waddle seal in the McMurdo Sound of Antarctica. (McMurdo Oceanographic Observatory)
According to Zico, “Voice can only be a bonus communication element to stand on all low-frequency sounds, such as switching to a different channel for communication.”
It is theoretically possible that sounds are included in the echolocation, the biological sonar that employs animals such as dolphins and bats to find their way around dark spaces. But so far, there is no evidence that seals use echolocation, the researchers said.
The team added that this behavior cannot be outside the expression of seals that can dive more than 1,900 feet (600 meters) underwater and hunt in the darkness of the Antarctic winter.
Let’s see if Wookie tries it.
This article was originally published by Live Science. Read the original article here.
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