Human evolution has gone through four long stages: ape human, primitive human, intelligent human and modern human. But have you ever thought about what kind of human will evolve in the future? This problem is not only Xiaobian wants to know, but also scientists are full of curiosity about it.
Therefore, they have done a lot of research, analyzed the human body condition, future lifestyle and environmental changes, and made a bold speculation: in millions of years, the Y chromosome will disappear!
As we all know, the human body has 23 pairs of chromosomes, including 22 pairs of autosomes and one pair of sex chromosomes, and the existence of sex chromosomes determines the human sex.
The male sex chromosome is XY, the female sex chromosome is XX, and the male sex is determined by the Y chromosome. If the Y chromosome disappears, does that mean that men will also disappear? The whole world has become a “daughter country”!
According to the research on the evolution and variation mechanism of sex chromosome, the evolution rate of Y chromosome is much faster than that of X chromosome, and it is constantly degenerating and mutating, which will lead to a sharp reduction of genes on Y chromosome. In this way, the Y chromosome may disappear completely, so we can speculate that men will disappear with it.
At present, this is only a conjecture. The disappearance of the Y chromosome, which determines the sex characteristics of men, may not mean that men will disappear completely.
The complete disappearance of the Y chromosome does exist in some mammals, such as the mole, for example. The sex determination system of mole vole and two species of Japanese Citellus has developed into XO, which indicates that its sex determination function has been replaced by other genes.
In other words, if the human Y chromosome disappears completely, it may be replaced by a new gene that determines reproduction, and then let the human continue to maintain the function of reproduction.
Although from the evolutionary point of view, the Y chromosome has been getting shorter and shorter since its appearance, it is uncertain whether the Y chromosome will develop as predicted due to the changes of various external factors.
In fact, whether the Y chromosome will disappear or not in the future, we must firmly believe that through more and more mature scientific and technological means, human beings are fully capable of genetic modification and replacement to solve this crisis, so there is no need to worry that men will disappear from the world.