Evolution of Human Speech Versus Primates

A new research and study of the primates have found a link between vocal repertoire and the relative size of key regions of the brain. Human speech involves species- specific anatomy. The speech was derived with the descent of the tongue into the pharynx. The shape of the human tongue and position provides the 1:1 oral to pharyngeal proportions of the sub pharyngeal vocal tract located above the larynx.

Though the vocal tract and larynx is similar in form and functions amongst practically all terrestrial mammals which includes humans too, but though relative to humans, the primates produce a very limited range of vocalizations.

However, speech also requires a brain that can repeat and with ease, reorder a number of motor gestures to form potentially infinite number of words and sentences. The ability to produce accurate sounds of speech and that to in rapid succession is something as humans we take for granted. However, if we really study the speech process we will be amazed how extremely involved process it is. Just imagine to produce a sound correctly the, lips, the tongue, jaw, velum, and the larynx must make the accurate movements each at the precise time or else the intended sound will get distorted. It is an example of mind-blowing split second coordination. Speech production is a complex process that requires network system of brain areas each contributing it its unique way.

The primates lack those brain mechanisms that are needed to produce, control and coordinate the complex vocal production.

By: Madhuchanda Saxena

Content: http://www.sci-news.com/othersciences/anthropology/primate-study-evolution-human-speech-06302.html