Why can't monkeys talk? Blame their brains

December 13, 2016, 7:21 a.m.
macaque whispering into another macaque's ear
Photo: jinterwas/flickr

Monkeys have the working anatomy to talk. It's just that their brains aren't wired to get the words out. That's the conclusion of a new study published in the journal Science Advances.

Using X-rays, researchers tracked the movement of a macaque monkey's mouth and throat while it was vocalizing, eating and making a wide range of facial expressions. They then used that data to create computer models of what the monkey's vocal anatomy was capable of, according to NPR, including a simulation of the macaque saying short phrases such as "Happy holidays" and "Will you marry me?"

They discovered that the anatomy of the monkey's vocal tract would allow the macaque to produce five vowels which, the researchers say is "an adequate range of speech sounds to support spoken language." And human listeners could easily understand the "speech" created with the monkey speech simulator.

Take a listen and see what you think:

So the problem isn't with the monkey's anatomy; it's somewhere in the monkey's brain.

"As soon as you had a brain that was ready to control the vocal tract, the vocal tract of a monkey or nonhuman primate would be perfectly fine for producing lots and lots of words," author Tecumseh Fitch, a cognitive biologist at the University of Vienna, tells NPR.

But the monkeys' brains don't have direct links to the neurons controlling the tongue and larynx, Fitch says. They also don't have key connections in the brain that make them capable of imitating what they hear, like humans do. So when it comes to speaking, it really isn't a case of "monkey see, monkey do."