Presumably everyone has seen mixed-race people in life or on TV.
Different races came together because of love, and gave birth to mixed-race children. Their appearance is obviously different from ours, and most of the mixed-race children are very beautiful.
But this also made many people fall into thinking, obviously they are all different races, why is there no “reproductive isolation” between people?
What is reproductive isolation?
The so-called reproductive isolation is also called reproductive barrier clinically.
Biologically, it refers to being affected by reproduction. Even if the geographical relationship is very close, groups of species cannot mate, even after mating. Infertile.
Even if it is fertile, the next generation does not have the ability to continue to reproduce. This is reproductive isolation.
For example, many people have seen a domestic animal called a mule in the countryside, It looks like both a horse and a donkey, but in fact it is the offspring produced by the combination of a horse and a donkey under the condition of human intervention.
However, it has reproductive defects. The pelvis behind it cannot open and close normally, and the mule cannot conceive the next generation. This is a typical reproductive isolation.
This has to mention a substance called gene, according to Darwin From the perspective of the theory of species evolution, the reason why organisms can reproduce is that most of them use DNA as the genetic material, and the structure of DNA is quite stable.
However, under the influence of various factors, it will gradually mutate and develop into a gene mutation, and the gene mutation will continue to accumulate during the evolution process.
Affected by gene mutation, a certain organism has changed from its original family DNA, resulting in reproductive isolation.
Why is there no reproductive isolation between people?
Reproductive isolation is always accompanied by some morphological and genetic changes, but there is no reproductive isolation among humans.
The reason why people are divided into different groups is that race is the result of social intervention and human selection.
According to the difference in skin color, we divide human beings into yellow race, white race and black race, but this is not actually the result of genetic determination.
The common ancestor of human beings, that is, from the African “grandmother” 200,000 years ago, everyone belongs to the human family.
Regardless of skin color and appearance, all human beings are just a subspecies. From a clinical point of view, if a race has different appearances, but there is no reproductive isolation, it means that the separation time between creatures is not long, and the body does not have too many gene mutations.
Or the organisms are affected by various other factors. Although they are divided into different family types, they still maintain a small difference in gene exchange.
As mentioned above, humans originated in Africa and walked out of Africa 65,000 years ago Global development, but human beings still maintain gene exchange.
Affected by the external environment, natural selection, social selection, etc., people living in different regions have huge differences in skin color, appearance, and height, but the differences in genes in the body are not the same. It’s not big, and no special subspecies have been formed. In fact, everyone’s essence is human beings, belonging to Homo sapiens.
Since there is no change in the genes, different skin colors and appearances The combination of people can also give birth to the next generation, and the next generation is also capable of reproduction. After all, the essential DNA of human beings has not changed.
The division of human races is actually meaningless. It is a grandstanding and ignorant clown’s practice to distinguish between people by skin color and appearance. As human beings, we are all equal.