https://www.sapiens.org/language/primate-speech/
We all know that parrots can talk. Some people may have even seen elephants, seals, or whales mimicking speech sounds. So why can’t our closest primate relatives speak like us? Our new research suggests they have the right vocal anatomy but not the brainpower to use it.
Scientists have been interested in understanding this phenomenon for centuries. Some have argued that nonhuman primates didn’t have the right-shaped body parts to make the same sounds as we do, and that human speech evolved after our speech organs changed. But comparative studies have shown that the form and function of the larynx and vocal tract is very similar across most primates species, including humans.
This suggests that the primate vocal tract is “speech ready” but that most species don’t have the neural control to make the complex sounds that comprise human speech. When reviewing the evidence in 1871, Charles Darwin wrote, “the brain has no doubt been far more important.”