Helium Gibbons use the same vocal techniques as the best opera sopranos
Gibbons are divas of the jungle. The little monkeys use the same technique to project their songs through the forests of Southeast Asia as the high-level sopranos singing at the Metropolitan Opera in New York or at La Scala in Milan.
This was the conclusion of research conducted by Japanese scientists who tested the effect of helium gas on gibbons’ calls to see how their song changed when their voice sounded abnormally high.
Much like professional singers, the experience revealed that animals were able to amplify higher-pitched sounds by adjusting the shape of their vocal tracts, including the mouth and tongue.
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The Sopranos: Gibbons uses the same technique to project his songs through the jungle as the best opera singers
It’s a skill that only a few humans master, but gibbons are able to do it with minimal effort, according to Takeshi Nishimura of the Primate Research Institute at Kyoto University.
Singing gibbons with helium might sound eccentric, but Dr Nishimura said it was a logical way to test how animals controlled vocalization when resonant frequencies in the vocal tract shifted upward.
“Using the helium environment, we can easily see how the resonance works and how the gibbon is making its loud, pure calls,” he said in an interview.
His team used a captive white-handed gibbon to record 20 calls in normal air and 37 calls in a helium-enriched atmosphere to show how animals could consciously manipulate their vocal cords and vocal tracts.
Soprano opera singers like Danielle De Niese use the technique to maintain volume when singing high notes
They found that the gibbon’s vocal tract had been adjusted by analyzing the sounds it produced. Helium causes its distinctive effect because sound travels much faster in gas than in air.
Singing is especially important for gibbons, who use loud calls and songs to communicate through the dense jungle.
Their exchanges, described by primatologists as “duos”, can go up to two kilometers (a little over a mile).
“Our data indicate that the acoustic and physiological mechanisms used in gibbon singing are analogous to human soprano singing, a professional opera technique,” wrote Dr. Nishimura and colleagues.
The ability of professional sopranos to fine-tune the resonances of their vocal tracks allows them to maintain their volume as they strike the high notes.
The fact that gibbons can do the same suggests that the complexity of human speech may not have required specific changes in our vocal anatomy.
The team’s findings are published today in the American Journal of Physical Anthropology.
AUDIO: claimed to be Gibbons sound on helium