Scientists have found that chin of a person not connected with the development of speech. He appeared in the process of evolution by reducing the effects of testosterone on organisms males. For many years, this feature was fixed and now has been passed on from generation to generation.
"Of course, such a thing may seem too trivial, but chins are so interesting for us for the reason that only man has a similar feature. This is a unique trait of our species," says Nathan Hollon from the University of Iowa.
The first theory, according to which the chin developed as a result of socialization, was wrong, say experts from America. It is the hormone testosterone, in their opinion, have shaped the modern view of the lower jaw.
"In a nutshell, we are unable to find any signs that the man's chin is associated with mechanical properties of the jaw, and even in some cases, on the contrary, reduces its strength. Overall, all this suggests that the chin is hardly linked with the need to dissipate tension and strain, and that in his birth involved something else." "explains Holton.
Hormonal theory sounds plausible. Most hormones affect the formation of the human form, and testosterone is no exception.