Porpoise, a kind of toothed whale that can use “fry voice”
Shutterstock/Onutank
Toothed whales, such as killer whales and dolphins, use air-powered nasal blasts to help hunt prey hundreds of meters deep. The echolocation system, which uses the power of the nose, works under extreme water pressure and allows whales to vocalize in different vocal ranges. This is an ability previously only seen in crows and humans.
As top predators of the ocean, toothed whales often dive to depths of 2 km in search of prey. Whales echolocate using loud, quick clicks, but researchers initially didn’t know how to accomplish this feat because whale lungs collapse at depths greater than 100 meters. Previous studies have confirmed that sound does not come from the larynx (the vocal organ of humans and most mammals), but radiates from the nose.
To understand how this works, Coen Elemans and his colleagues at the University of Southern Denmark trained two Atlantic bottlenose dolphins (Truncated Tursiopus) and three porpoises (come on come on) voluntarily accepting the endoscope into the blowhole. Using a high-speed camera attached to a scope, we peered into the nose of each animal echolocating for food in the open ocean. The nose tissue moved with each click.
In the lab, researchers pumped air through the noses of already dead porpoises and found that those tissues moved in a similar way. They identified a narrow passageway in the nose called the sonic lips as the culprit. When a toothed whale’s lungs collapse, it forces oxygen into its muscles, forcing a small amount of air into this nostril. Air sways back and forth through Phonics’ lips, helping the porpoise to make loud clicks as high as 200 decibels. This is bigger than fireworks and enough to permanently damage a human ear.
“They basically push. [air] One way is to recycle it and push it back without breathing,” says Elemans. “It certainly surprised us.”
Further sound analysis and a digital model of the nasal passages showed that, like humans, toothed whales have at least three vocal ranges. Vocal fly register (low screeching voice), chest register (normal speaking) and falsetto register. (high-pitched, squeaky sound). Their nasal echolocation trick lies only in the vocal fly register, which requires the least amount of airflow to produce a click.
Producing sounds with their noses gives whales more control over the sounds they make, freeing up their larynx for other important uses. This means you can block the airflow between your lungs and your nose, allowing you to apply pressure to your nose during deep dives without risking lung damage.
“All the sounds they make are produced by phonic lip located in the nose and larynx. [becomes] It’s a really good plug,” says Elemans. “In doing so, they can make much louder sounds than any animal on earth.”
The discovery that toothed whales can make sounds in different vocal ranges raises new questions about toothed whale communication, says Stephan Hugenberger of the University of Witten/Herdecke in Germany.
“Yes, different voices, but what for? And how do they use them?” says Hagenberger.
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