Lead
"How do humans lose their hair, and what do we still have hair for?
Why can't we take out our hair, armpit hair, and pubic hair when it's so hot in the summer?"
These questions have always bothered Xiaole, so he began to look through various books and materials to find answers.
Xiaole knew that humans originally had a lot of hair, but in Darwin's theory of evolution, human hair gradually decreased, and eventually evolved into light and short hair, which is also a sign of the gradual evolution of humans from animals.
But what is the purpose of the gradual loss of human hair?
Xiaole wanted to find out, so he came to the ocean of knowledge to explore and learn.
First, the role of hair.
Hair on the human body is not useless, whether it is on the body of humans or animals, hair has a certain purpose.
Hair has many functions on animals, such as keeping them warm, keeping them warm in the cold season, and it can also help animals camouflage them from predators.
In addition to the above functions, hair also has a protective effect.
Hair can protect the animal's skin from the external environment, and can also help the animal sweat and excretion.
Hair can also help animals defend themselves against predators, and hair can also provide nutrients for animals.
From the above several functions, it is clear that hair is very important for animals.
At first, human beings had a lot of hair, but as humans evolved, the hair gradually became less and less, until it became what it is now.
In the process of human evolution, the role of hair has gradually weakened, but there are still some hairs on human bodies, and what are these hairs for?
In Darwin's theory of evolution, human hair is gradually decreasing, but the head, armpits, and pubic hair are not changing, why is that?
Why do human heads, armpits, and pubic hair remain?
Are there any special uses?
Xiaole was very curious about this, so he decided to continue his studies to find the answer.
2. Causes of human hair loss.
In Darwin's theory of evolution, human hair evolves gradually.
As human beings become more and more capable, the role of human hair on the body has gradually weakened, but human hair has not completely disappeared, which shows that human hair still has a certain use.
How did human hair evolve over time, and what did it exist for?
Evolutionary theory suggests that human hair gradually decreases and eventually evolves into light and short hairs, mainly to dissipate heat and improve endurance for long-distance running.
In the tropics, the climate is very hot, and if there is more human hair, it will inevitably cause a decrease in the body's ability to dissipate heat, so it is easy to suffer from heat stroke.
In addition, when running long distances, it is easy to affect the speed of hair more, so gradually reducing hair is to better adapt to the climate and environment of the tropics.
In addition, it is easy to get sick because of the large number of hairs, such as lice and bacteria, so in order to reduce the chance of getting sick, human hairs are gradually decreasing.
The role of hair is gradually diminishing and decreasing, but there are still some hairs on human bodies, and what are these hairs for?
Xiaole continues to explore to find answers.
When humans run long distances, a lot of sweat comes out, which leads to the loss of water and electrolytes.
In order to maintain the balance of water in the body, the body temperature of the human body rises rapidly, which puts the human body at risk.
In order to better adapt to the tropical environment, human beings will produce a lot of sweat, which will lead to the human body in a state of lack of water, in order to be able to better survive, human hair will gradually decrease, to adapt to the climate of the tropics.
3. The role of hair.
In humans, the amount of hair is the largest.
And there are still differences in the number and density of hair, for example, in the northern region, people's hair will be longer and thicker, while in the southern region, people's hair will be shorter and sparse.
When did human hair start to decrease?
On the top of the human head, the hair is the most, and in the lower part of the hair, the hair will gradually decrease, until there is none, Xiaole is very curious, in terms of the role of hair, what is the role of human hair?
On the top of the human head, hair is the most numerous, which means that hair is very important, so how did hair originate?
According to evolutionary theory, human hair evolved gradually.
In the process of evolution, the amount of hair has gradually changed in response to changes in the environment.
In the beginning, humans existed in the form of apes, and their hair was very thick, because apes lived in the forest, and their thick hair could protect their scalps from being harmed by vines and beasts in the dense forest.
When humans left the forest and began to live on the plains, human hair began to decrease.
This is because when humans are hunting, it is easy to become a target for animals to catch when they have more hair, so gradually reducing the hair can protect the head from being scratched by the animal's claws.
With the change of human living habits, the number of hairs is gradually decreasing, because the hair is easy to breed lice, bacteria, etc., so that humans are prone to diseases.
Therefore, in order to better protect the head and reduce the chance of getting sick, human hair is gradually reduced.
However, there will be more hair on the top of the head and forehead in direct sunlight, which is to protect the head from the sun.
When it is cold, the hair will play a certain role in keeping warm, which can protect the head from the invasion of the outside cold, so the hair gradually increases.
Also in the hot summer, the hair will play a certain role in heat insulation, which can protect the head from direct sunlight, so the hair will gradually increase.
In the northern region, the living environment of human beings is relatively cold, and in the southern region, the living environment of human beings is relatively hot, so in the process of migration, human beings will change the amount of hair according to the living environment to adapt to the living environment.
Fourth, the role of armpit hair.
In human armpits, there will be less armpit hair, which has a lot to do with the environment under the armpits.
In the human armpits, the sweat glands are more developed, so the sweat will be secreted more, in order to be able to better perspire, the armpits will become more humid, so that bacteria, fungi, etc., will breed, so the armpit hair will be relatively less.
In the absence of hair under the armpits, it will perspire better and will not breed bacteria, fungi, etc., so the armpit hair will gradually decrease.
There is also a benefit to having less armpit hair, because more armpit hair is easy to breed bacteria, fungi, etc., which can easily cause inflammation, so gradually reducing armpit hair can reduce the occurrence of inflammation.
There is also an advantage of less armpit hair, that is, it can well avoid the armpit hair being pulled, so that people will not feel uncomfortable and will not easily cause inflammation.
5. The role of hair in private parts.
There is very little hair in the intimate area, because less hair in the intimate area is cleaner.
When humans reproduce, they need to combine sperm and eggs in order to give birth to new life.
When there are no clothes, human beings live naked, so in order to better reproduce offspring, there will be less hair in the private parts, which can help the sperm and egg to combine without being affected.
When there are no clothes, humans live naked, and the increase of hair on the private parts will cause discomfort such as itching, so the hair on the private parts will gradually decrease.
At the same time, the hair of the private parts also has a certain protective effect, which can well protect the private parts from external damage.
During sex, the hair on the private part will play the role of a sheath, which can protect the genitals from the invasion of bacteria, and can also reduce friction for better sex.
epilogue
In the process of gradual reduction of human hair, it may be affected by many factors, such as the environment, behavioral habits, etc., which will change the number and density of hair, so in the process of gradual evolution of hair, it is necessary to consider comprehensively, and not to see many.
The function of hair may also change with the development of human society, and some functions may no longer be important in modern society, so we still need to learn and explore in many aspects.
There are still many unknown factors in the evolution of hair, which requires more people to explore and study.