Monkeys are four-legged mammals that are closest to humans in body structure and origin. There are two main types of monkey: New World monkeys (platyrrhine) from Central and South America and Old World monkeys (catarrhines of the super family Cercopithecoidea) from Asia and Africa.
The animal world is very diverse. Animals are varied in appearance and abilities. It's no a secret that many animals outperform humans in their abilities. For example, dogs are a thousand times better at distinguishing smells than humans; cats are a hundred times better at seeing in the dark. Bats and dolphins let out ultrasonic impulses with a large frequency (up to a thousand per second), and then follow the sound and determine what happens before them. This ability helps them navigate in total darkness and turbid water. Another great ability is shown by fishes. Some fish have a wonderful ability to electro-locating. Generating short electromagnetic impulses, they use an electric field to identify any (not only alive) remote objects and even to communicate with each other. Some fish have gone even further. They use electricity not only for electro-locating, but also as a weapon. Such electric fishes are catfish, cramp-fish and eel fish. Also among mammals there is a possessor of chemical weapon and this is a skunk. Skunk is an animal with size of a cat, living in America. In the case of threat, skunk emits an ineradicable stench and this is enough to repel any predator. Fantastic abilities have chameleons. Famed chameleons can change their colour. Cells, which are underneath the skin of a chameleon, can give it a very different colour, which depends on the external factors and by the mood of the animal itself.
All these animal’s possibilities are stunning, but what about the ability to speak? A lot of birds are able to imitate the human speech. The most capable in this regard are Jaco parrots, whose vocabulary can number dozens of words. Recently, more and more researches have appeared, according to which the bird's brain is much more complicated than previously thought, so do not be too surprised that some birds may well master "speech tricks."
The famed parrot Alex who had a vocabulary of more than one hundred words.
So why are monkeys, the most approximated in structure to a human, do not know how to talk?
There are two theories on this issue. The first theory was proposed by Darwin. He came to the conclusion that inability to speak is related to the structure of the monkey’s brain, which is not so developed to cope with complex speech communication. Most scientists were confident in this theory until the late 60s of the last century. But after publication an article by the American researcher Philip Lieberman and his colleagues, who carefully examined the oral cavity and larynx of a dead macaque and made its plaster model, one more theory was strengthened. According to it, the structure of vocal cords, larynx and oral cavity of monkeys does not allow reproducing wide spectrum of sounds that a human's throat is capable of.
Philip Lieberman is a cognitive scientist at Brown University, USA. He was born in 1934 and studied electrical engineering at Massachusetts Institute of Technology. Lieberman’s career has focused on topics in the evolution of language, speech and relationship between cognition and language.
Scientist Lieberman and his colleagues measured a plaster model of a macaque’ larynx and entered the resulting data into computer to find out how wide is a spectrum of sounds the macaques can produce.
Was find out that the sound capabilities of macaques are extremely limited and do not even approached to human’s. Even if the monkey's brain had enough for complex speech, for mechanical reasons, macaques would not have coped with it.
Latest research.
Scientists are very concerned about the question whether monkeys can speak or not. Therefore, various researches are constantly conducted. So, recently a group of European and American biologists conducted a study and proved that Philip Lieberman significantly "miscalculated." The team led by professor William Tecumseh Sherman Fitch III, a cognitive scientist and an evolutionary biologist at the University of Vienna, studied alive macaque and took advantage of roentgen. First, scientists taught the monkey to sit during the scan, and then, using X-rays, photographed monkey’s throat in various activities: in screaming, eating and various expressions of the muzzle. It was revealed 99 different positions of the vocal cords, muscles and tissues. The resulting spectrum of sounds did not differ from the possibilities of man.
So, it's practically proven that from a mechanical point of view monkeys can properly imitate human speech. Their abilities do not completely coincide with human’s, for example, monkeys could not utter the sound "e", but people would understand their speech without problems.
On sceptical remarks of scientists, and Philip Lieberman in particular, Fitch and his team indicate that their research was conducted on a living monkey, rather than on a plaster cast. Therefore, their results should be considered more accurate. Fitch says that the absence of any form of speech in monkeys, apparently, is connected with their brain and adds that Darwin was right.
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Good post. Have an upvote.
I wonder if just saying it is a purely mechanical problem and not a feedback loop between the species needs and the evolution of the brain and vocal chords.
Did humans evolve language and the brains and vocal chords because it made us better hunters? Or better parents? Or better and just coordinating the tribe and sharing resources?
Maybe monkeys and apes don't have these pressures?