Over the water, they sound like wookies. Under the ice, they look like chirping, chattering robots. Either way, Antarctica’s Waddell Seal should have no problem finding work in the upcoming Star wars Assignment or Project.
“Waddell seals make an incredible, secondhand sound under the call ice,” said Paul Cziko, a visiting professor at the University of Oregon and lead author of a new study. “It really feels like you’re in the middle of a space war Star wars, Laser beam and all. “
The catch: You must be an alien (or droid) to hear them; All those sci-fi sounds are completely inefficient for human ears.
Two years after listening to Waddell Seals, Cziko and his colleagues were able to detect the other’s noise (Leptonychotes weddelli) In 2017 with a special hydrophone (an underwater microphone) installed in McMurdo Sound, Antarctica.
Before the researchers began recording, scientists were aware of 34 seal calls to human ears. Now, team research – published online on December 18 Journal of the Acoustical Society of America – The repertoire of seals includes nine new types of ultrasonic calls. Those sounds include trills, whistles, and alien-sounding chirps, sometimes composed of multiple harmonic tones.
Researchers said that humans listen in the sound range of 20 to 20,000 Hz (or 20 kHz). Most newfound seal sounds exceeded 21 kHz, some continuously increasing to 30 kHz.
Above: A visual representation (spectrogram) of one of the nine ultrasonic call types. The U-shaped features in the upper half of the plot are part of the call type U101.
A high-pitched whistle reached 49.8 kHz, the team wrote – and when the jawans reconciled several tons, the resulting noise could exceed 200 kHz. (This is beyond the hearing range of cats, dogs and even some bats.)
What are all these high frequency communications about? Researchers are not sure; Until now, scientists had never detected ultrasonic vocalization in seals (nor in any other winged mammal, such as sea lions or walrus).
According to Cziko, sounds can be a bonus interactive element “like standing in a separate channel for communication, all standing out at low-frequency noise.”
It is theoretically possible that noise is involved in echolocation, the biological sonar that animals such as dolphins and bats serve to find their way around dark places. But so far, there is no evidence that seals have used echolocation, the researchers said.
Still, the behavior would not be out of character for a dismissal that could dive more than 1,900 feet (600 meters) under water and hunt in the darkness of Antarctic winters, the team said.
Let’s see how a wookie tries to do this.
This article was originally published by Live Science. Read the original article here.