7,000 years ago there was a crazy phenomenon happening to men around the world that until now science still doesn't understand why

At one point in the past, the number of men declined to only 1:17 women. What happened?

The history of world biomedical history has recorded strange phenomena so strange and this 7,000-year-old event is a very typical example.

Specifically, this is a time to witness a terrible collapse in the number of genes of . men, lasting up to 2,000 years. According to a new study published in Nature Communication, the chromosome (Y chromosome) has been missing for generations. At one point in time, the number of men in the Old World was only 1:17 compared to women.

Old world: The name Earth was known by Europeans before Christopher Columbus discovered America in 1492. The former world includes: Europe, Asia and Africa (also known as the African continent- Asia-Europe) and the surrounding islands.

The question is why, and what caused this phenomenon. In fact, this is not a new phenomenon mentioned, when there has been quite a lot of research to confirm that Y chromosomes have disappeared a large number in the past. However, the conclusion about the cause is not the same.

In 2015, a British study published in Nature first mentioned this phenomenon. They argue that a large number of men disappeared by the time people moved from hunting - gathering to farming and farming.

The hypothesis is that at this point, some men become dominant in power, and they impose, dominate the fertility of the under-residing population.

This does not necessarily mean that the total number of men decreases. The problem is that conception and the birth of a boy are hindered, causing the Y chromosome to gradually shrink. As a result, the genome also collapsed.

The most reasonable hypothesis is available

Their conclusions received the approval of many historical experts. However, the research team from Stanford University did not think so. Recently, they turned the issue over with a different approach.

Using mathematical models and computer simulations, they trace back to the tribes that caused a lot of war to seize resources, and track Ys across the entire population.

The ancient tribal wars make the gene allocation narrow.

For those who do not know, the old lineages often follow patrilineal ancestors, meaning that these tribes already have a low Y allocation rate because all lineages depend on several men in power. And through Stanford research, these wars actually caused the distribution of chromosomes to fall even lower.

In biology, this is called the "bottleneck" phenomenon - occurs when the biodiversity of a population is reduced.

War causes death - whether men, women or children. But because the proportion of men is always the majority in the army, the proportion of men dying is also more skewed. Therefore, after the war, the number of women is usually higher than that of men.

Moreover, the old wars are extremely barbaric. The winner often destroys the loser, and that may be the reason for the "bottleneck" phenomenon.

Experts are behind research.

But even so, this conclusion is still a lot of loopholes and cannot be affirmative. Even experts from Stanford have just said that this is a hypothesis, no more.

Just knowing that historical facts only confirm that there is a bizarre phenomenon happened to men, but does not show why. And the confirmation of the cause is still lowering the resolution.