Let me start from here. Beard is one of the foremost sexually dimorphic feature of human. That is, beard is a distinctive feature that makes a male to be easily identified from a female. The presence of the hormone testosterone give men the ample opportunity to grow beard as they attained stage of puberty. Women don't have facial hair, except in some cases when there is an imbalance of hormone a trace of testosterone or when they have more than normal androgen which is a female hormone.
When you see a man with beard, what first come to your mind is that he is a strong man, because the beard is an indication of social dominance. Some says the presence of facial hair intimidate other men who lack it or have their own shaved. Those who have scanty facial hair, normally goes for testosterone supplement just to have it on their face to save them from embarrassment.
Violence between male folks
It is common that high percentage of violence is known among men, women are not exceptional though, but most times, men engaged in fisticuff to show dominance possibly over a territory or to show to the females that they can care for them when the need arises.Charles Darwin the renowned naturalist, father of theory of evolution and also the owner of magnificent beard claimed that male facial hair is just to attract female. He however see the lion mane as means of physical protection for the lion.
Facial bone at the receiving end of male violence
If you have ever watched boxing either the one inside the ring or possibly in a party joint or even at a bar, the targeted part is the face. Human face is at the receiving end during fight and most times at the end of the fight, the face is left with various degrees of injury. Studies has suggested that man facial bone might have evolved in other to reduce the impact of punch on it. It was argued that several thousands of years back, human do compete for limited resources such as food, women, water and amenities available during their time. So the male then do engaged in exchange of punch just to survive. As a result of that, over time human male bone structure evolved to survive blows received during fight.
Skull skeleton of human
We need to know that both in the early man and the modern man, the part of their facial bone that experience fracture during man to man fight is also the one that manifest substantial level of sexual dimorphism. Researchers claimed they could rightly assert it that facial bone evolved as a result of sexual selection and to protect the face from damage due to violence. That part of the facial bone that used to experienced fracture then is the one that evolved. A study earlier carried out in the UK shows that during physical assault, 83% of injury are fractures on facial bone.
How human cheek bone evolved
There are two contradictory school of thought among anthropologists about how human facial bone evolved from human ancestor to modern man. One school of thought claimed that the dense facial structure evolved so as to help man chew hard food such as nuts. However, this school of thought failed to explain why males facial bone are larger than females since both sex have similar diet.
The other school of thought claimed that the cheekbone of hominid evolves more than that of other primates. In other words, as the primates evolves, their jawbone evolves as well. The jaw bone evolve to become bigger and profuse as well as the bone around the nose and eyes.
They also claimed that human anatomy is as a result of violence. This include the claim that human hand evolved to form fist for the purpose of combat, they also claimed that the time hand evolved is also the time man develop abundant facial bone. Alongside the facial bone of man comes the beard as well, a unique sexual dimorphic fearture
Beard another sexual dimorphic feature protecting human man facial bone against fracture during fight
Like i earlier stated, Charles Darwin the father of evolutionary theory put it that man beards is mainly to attract the opposite sex. However, some researchers came up with something that is contrary to that claim. They claimed that instead of the beard serving just the ornamental purpose, it also serves to save facial bone from being fractured easily. How ? They claimed that the facial hair for men also evolved to protect facial bone during fight. You will agree with me that facial hair is not only peculiar to human man, it is also seen with African Apes and the facial hair is possessed by both male and female apes, but in human, it's only possessed by man while this feature is reduced in females. I explained earlier that the hair growth on the face of human man is a function of the hormone testosterone which is a sexual hormone for man which is absent in female folks.
Just like a well built man with masculine skeletal feature gives the man social dominance , a man with full beard is also perceived to have social dominance, and perceived to be aggressive when compared to a man with clean shave.
The presence of full beard on a well developed facial bone will ordinarily give the man an intimidating look when compared to others. Could it be said that the beard serves as protection for the man facial bone, his throat and jaw during a fight? Well, i have only seen few boxers with beard. Most do have clean shave. In a research report, it was demonstrated in the laboratory how models were used to illustrate the impact of blow on full beard, trimmed beard and hairless faces.
In the research, short fiber epoxy composite bone which has same properties to human cortical bone was covered with sheep fleece and it was well conditioned to resemble human facial bone covered with beard. Two others were designed in such a way that it resembled clean shaved face and another one that resembled trimmed facial hair. The three models were subjected to an heavy impact which weight is 4.7kg. The three experienced the impact but according to the report, the epoxy composite bone covered with the sheep fleece was able to diffuse the impact more than the two other models which represent clean shaved and trimmed facial hair. The full beard model was able to reduce the impact as a result of the fleece thereby reducing the impact of the blow on the epoxy composite bone which act as the bone. That was not the case with the remaining two.
Though it can not be authoritatively said that presence of full beard on the face can be an advantage during professional or amateur fight, as there are other report that do not substantiate the claim, but one can say that the presence of the hair on the face might prevent laceration or fracture depending on the thickness of the hair.
Parting Word
Would you leave your beard to grow and if you do, for what purpose?
Mind you its main reason might be for ornamental purpose as rightly put by Charles Darwin to show some form of dominance or you would just leave it to protect your MANDIBLE from being dislodged during a fight. Who knows you might need it one day
https://www.livescience.com/beards-protect-face-punches.html?
https://academic.oup.com/iob/article/2/1/obaa005/5799080
https://www.livescience.com/46216-male-faces-evolved-for-fighting.html