a Thick beard appeared among men to protect the lower jaw from fractures – this is the conclusion reached by scientists after a series of experiments.

writes Integrative Organismal Biology, samples of a jaw with an artificial beard much more effectively absorb the energy from impact with a blunt object.

in addition to the protective function, in ancient times, the dense vegetation on the face attached to its owner more masculinity and aggression.

Researchers from the University of Utah led by David Carriera checked the assumption of a protective role of beard. For this, they created models of the jaws made of fiberglass, stick them on pieces of sheepskins.

In some designs, the length of hair was about eight inches on the other – half centimeter, on the third it was removed. The models were placed on the anvil, which lowered the rod weighing about five kilograms and a diameter of three centimeters. The height from which he fell, picked up so that when you hit the fiberglass with intact skin did not leave visible dents and cracks.

Fixed the falling speed of the goods, its acceleration at the moment of contact of the jaw, the energy absorbed by the skin, and the resulting load on the sample.

as a result of experiments it turned out that jaw with long hair absorb on 30 – 37 percent more kinetic energy at impact than with short. Consequently, a thick beard can protect the lower jaw from damage. For example, during a fight.