Teleology & evolution: Vocal cord development (Introduction)

by David Turell , Saturday, December 10, 2016, 23:38 (2699 days ago) @ David Turell
edited by David Turell, Sunday, December 11, 2016, 00:05

Current research on monkeys, using special x-ray video techniques, finds that monkeys have the facility to speak with their current anatomy if they only had a brain to employ the ability. They don't:

http://medienportal.univie.ac.at/presse/aktuelle-pressemeldungen/detailansicht/artikel/...

"Monkeys and apes are unable to learn new vocalizations, and for decades it has been widely believed that this inability results from limitations of their vocal anatomy: larynx, tongue and lips.  But an international team of scientists, led by Tecumseh Fitch at the University of Vienna and Asif Ghazanfar at Princeton University, has now looked inside monkeys' vocal tracts with x-rays, and found them to be much more flexible than thought before. The study indicates that the limitations that keep nonhuman primates from speaking are in their brains, rather than their vocal anatomy.

"The scientists used x-ray video to see within the mouth and throat of macaque monkeys induced to vocalize, eat food, or make facial expressions. They then used these x-rays to build a computer model of a monkey vocal tract, allowing them to answer the question "what would monkey speech sound like, if a human brain were in control?" This showed that monkeys could easily produce many different sounds, enough to produce thousands of distinct words. Examples of synthesized monkey speech can be heard here:  

"This implies that a basic form of spoken language could have evolved at any time in human evolution, without requiring any changes in vocal anatomy."

Another source article:

https://www.newscientist.com/article/2115693-monkeys-should-be-able-to-talk-just-like-u...

"No one can say now that there’s a vocal anatomy problem with monkey speech,” says Asif Ghazanfar at Princeton University, and co-leader of the study team. “They have a speech-ready vocal anatomy, but not a speech-ready brain. Now we need to find out why the human but not the monkey brain can produce language.”

***

"What we’ve discovered is that the monkey vocal anatomy is capable of creating speech intelligible to us,” says Ghazanfar. But, he says, the macaques lack a speech-ready brain to control it.

"The team says its study also implies that the evolution of human speech capabilities required neural changes rather than modifications to vocal anatomy.

"There’s a growing body of evidence from all great ape species that there are few neural limitations,” he says. “Our closest relatives can vocally learn new vowel-like and consonant-like calls, both in the wild and in captivity.”

"Ghazanfar agrees that the evidence for their ability to make speech-like sounds is increasing, but says it is still limited. For example, he says, no monkey or ape comes close to the range of human-speech like sounds produced by one-year-old human babies.

Comment: Be sure to listen to the computer generated 'speech' examples on both websites. It appears our human specialized anatomy for speech improves our use of language, but is not required for a basic spoken language.