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Source: Zhihu.
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Hair itself is long to protect the animal body, but because of the great evolution of human brain and the development of science and technology, human beings no longer need some body hair, but need to continue to evolve completely.
The existing ones also have their functions, just like the appendix. Without the appendix, the risk of cancer is greatly increased.
In addition to men's personality traits, beards also have the characteristics of adsorbing harmful substances.
Recently, foreign experts found that beards have the characteristics of adsorbing harmful substances. When people breathe, they can discharge a variety of harmful chemical gases, all of which can stay on their beards; The atmosphere contains a variety of heavy metal particles, especially in busy streets, polycyclic aromatic hydrocarbons and lead emitted by automobile exhaust will also be adsorbed by beards; Smokers, carcinogens such as benzopyrene in smoke, will also stay on their beards. In addition, the epidermis of the beard secretes more oil, so it is often difficult to wash your face with water at ordinary times. Studies have shown that oil has the property of adhering to dust and microorganisms.
Foreign experts analyzed the shaved beard with gas chromatograph and found dozens of harmful substances, such as carbon dioxide, nitrogen oxides, benzopyrene and lead. Under the microscope, you can also see a large number of microorganisms on the beard.
It can be clearly seen from the shape of beard and respiratory airflow that the function of beard is to absorb harmful substances and prevent inhalation, and there is almost no obstacle to exhaled gas.
Historically, men have generally exercised much more than women, and men need beards more, which is basically the case now. Women also have beards, and scientific research shows that there are five grades of gender, so it is not surprising.
At the same time, beard is one of the gender symbols of men, and it is also the embodiment of the charm of mature men. China has a saying that "no hair on your mouth, no practical work". Scientifically speaking, it is proved that men secrete more hormones and do more things. Men's beards have also been given a deeper meaning. After cutting it off, the sign is gone, and a bar is missing.
Transferred from Zhihu
Personally, I think that in fact, at first, a person's beard should be a kind of protection like a long-haired beard. A man with a beard is a man, isn't he? O(∩_∩)O~