On the one hand, this design should take into account the basic characteristics that human beings must have on the earth, that is, they must have a head, a trunk and limbs, but they must walk upright and have a developed nervous system. Therefore, the cranial cavity central nervous system must maintain a certain amount, and it must be delivered from the vagina like the earth creatures. So through the timing design of gene expression, the skull is designed into several pieces. Before birth, there was no calcification in the seam, and only a basic number of neurons developed in the nervous system. After birth, a large number of nerve fibers, synapses, nerve endings and receptors, nerve endings and effectors are developed according to the interaction between individuals and the environment and the nutrients ingested by individuals. Nerve fiber myelin sheath and neuromuscular junction, in this process, the central nervous system and receptor effector form a complete information processing system. Just like our computers, there are also input systems, such as keyboards, output systems, such as printers, and complex information processing systems, such as central processing units.
The time sequence of this development is as follows in the sports system: two lifts, four turns, six sittings, seven rolls, eight crawls and walks.
That is to say, unlike quadrupeds such as wildebeests, people are born with mature nerves to control muscles, so they will run when they are born. Humans are born with the need to promote the development and maturity of nerve fiber myelin sheath and neuromuscular junction by ingesting nutrients in order to exercise. This developmental neural sequence is also related to location. That is, the neck neuromuscular motor system matures in two months, the head can be lifted, the trunk muscles can develop in four months, the trunk muscles can turn over in six months, sit still, roll over in seven months, and crawl in coordination with the upper and lower limbs as part of the muscle development of the lower limbs in eight months. At the age of one, the whole body is mature in coordinated movement and can stand and walk independently.
However, there are some fallacies in modern times, such as adding complementary food for 4-6 months and egg yolk allergy. I even heard that when I was one year old, I added whole eggs, which caused a lot of malnutrition. This malnutrition is characterized by normal height and weight, but the motor coordination ability of the nervous system lags behind. For example, you can't lift your head for two months, you can't sit up for six months, and you can't walk independently at the age of one.
The development of myelin sheath in nervous system needs a lot of cephalin and lecithin, so I feed the egg yolk at the full moon and steam the egg soup for three months according to the traditional parenting method of the elderly in China. The staple food of four-month-old children is eggs and rice porridge.
Nowadays, it is popular on the Internet to feed only milk powder and inferior rice flour for four months, which leads to normal height and weight of children and malnutrition of nervous system everywhere. Neuromuscular motor system and children with bradykinesia abound.
My children eat three more meals, four meals a day, one stool a day, two sleeps a day, four hours in the afternoon and eight hours in the evening. I used to eat fish soup and fish for four months, but now I can't feed salt at the age of anti-science My children are fed egg soup for three months without salt. How can I eat egg soup?
I feel that some people have committed some fallacies, instilled wrong knowledge and misled young people. Lead to this generation of children's nervous system development retardation. If it can lead to the slow development of the nervous system of most children in a country, then this country is in danger!
It's not easy!
[Covering your face] This problem is estimated to be that when God created man, he drank, and when he was drunk, he forgot to design, which made people feel less painful. [Laugh] [Laugh] [Laugh]
Other mammals have less pain during childbirth than human women. ...
Many scientists believe that this is caused by the huge brain (skull) of human babies ... In fact, the mortality rate of dystocia in human women is also the highest among mammals ... (Before the rise of modern medicine, the mortality rate of dystocia in women reached 2- 15%, and childbirth was like the door of death ... But with the improvement of medical level, the maternal mortality rate has now dropped below two ten thousandths ...)
Other animals, such as deer and sheep, basically grew up in their mothers' wombs. They can walk independently for several hours after birth, but human babies can't walk until they are raised for a year ... so some scientists think that human beings are absolutely immature. ...
Why can't humans grow up in their mothers' wombs before they are born? Because at that time, the baby's skull will be too big to be born. ...
So, human beings have evolved. We should give birth to semi-finished babies before the children grow up to reduce the mortality rate of women. ...
Nevertheless, the head and body of a human baby can still reach the level of one to one ... although the skull of an animal is very small. ...
In addition, to correct a problem, human beings have not evolved for hundreds of millions of years, and it has been about 5 million years since they started walking with their feet. ...
Walking upright will also make human pelvis narrow, making it difficult to have children. ...
Moreover, the brain capacity of early humans was very low (the brain capacity of modern humans was 1500ml), and the skull of primitive humans was not as big as it is now, so it was relatively easy for them to have children. ...
For example, the brain capacity of Australopithecus is only 500 ml. ...
Later, with the gradual enlargement of human brain, only women who are used to premature delivery can avoid dystocia. ...
Generation after generation, it has evolved into our modern people (late Homo sapiens) ...
However, some scientists insist that it was 1 10,000 years ago that when humans began to use grain, the fetus became bigger, which led to birth difficulties. These scientists oppose the "premature birth theory" of human beings and think that compared with animals, especially with relatives of other primates, human beings spend a lot of time with their mothers. ...
Of course, the scientific community has not yet reached an agreement on the specific reasons. ...
Childbirth is always painful and happy.
I think people who can lead a normal life are actually not as painful as those depicted in TV dramas.
May and I have three children: two women and one son. When Mei gave birth to her eldest daughter, her stomach just started to hurt, which was completely tolerable.
She said: I'm afraid it's going to give birth, and the little thing is tossing in the face!
It was ten o'clock at night, and I suddenly felt.
I said: Does your stomach hurt?
She said: not very painful, bouts.
Until dawn, I quickly borrowed human tricycles and dragged her to the hospital.
I was just 3 1 year old that year, and Mei was only 22 years old.
She was lying on a stretcher and was about to be pushed into the delivery room by a white coat, but she held my hand tightly.
The white coat said: what are you doing as a big man when a woman gives birth to a child? Wait outside!
May said, let him in. I'm afraid not. ...
Look at her in a white coat, then at me, acquiesced.
At 9: 35 in the morning, the eldest daughter gave birth and was red all over!
The obstetrician said: this anger is heavy and the whole body is red!
So I looked into Ya's eyes, and the baby didn't cry, but looked around with black-eyed beans.
The doctor added: fortunately, I didn't blink!
Mei didn't seem to hurt her vitality, just smiled and said, I can't eat anything without her!
After leaving the hospital for three days, Mei walked down the first floor from the sixth floor to the street, and then took a taxi back to the rental point.
When I got to the house, Mei sat on the bed and smiled at me: She slipped and came out where there were hands and feet in the hospital!
When she has a daughter, Mei still goes to work by bike every day until she can't move.
Mei gave birth to three children and didn't feel very painful. The evolution of human beings, I think that the brain and human body structure is more intelligent, more reasonable and more elegant, and it must be realized by squeezing children out of the birth canal. Caesarean section with a knife, I think there is no natural and smooth production science. As far as safety is concerned, being stabbed is not conducive to the postpartum recovery of the body unless absolutely necessary.
The process of life is like a seed taking root and sprouting. No matter how it evolves, the physiological structure of the human body cannot be reduced, and it must always maintain the needs of life.
That's a blessing, and I can have two babies. Ligation. Medical science
The premise is wrong, there were no humans 100 million years ago!
What can't be born or dystocia now is evolution. As a result, human beings continue to interfere, so it is more difficult to be born or dystocia in the future.
This is a natural choice. Maybe it will become smaller if the evolutionary conditions are met. For example, when people walk upright, the tail is useless and will disappear with time.
In fact, people are getting more and more melodramatic.
The pain is getting worse.
There are not so many facilities for animal delivery, such as manpower and material resources.
Let's just say that pain has evolved.