Why do couples with distant blood and geographical location give birth to smarter offspring?

The reason why the offspring of couples with farther blood relationship and geographical location are smarter is that the genes between them are more differentiated and easy to combine to produce better genes, while those harmful genes are not easy to pass on to future generations. So generally speaking, people who are not related by blood and geographically far apart are more beneficial to future generations after combining.

First of all, there must be no blood relationship. As we all know, inbreeding is easy to produce offspring with birth defects, because the genes of the two people who are combined are too similar. Everyone has 23 pairs of chromosomes, of which 22 pairs are autosomes and one pair is sex chromosomes. When two people combine, chromosomes will combine in pairs.

If two people are related by blood, and the structure and arrangement of their genes are very close, then it is easy to keep harmful genes, especially those recessive genes, and there is a greater chance to show them, that is, there is a greater risk of getting sick in the future.

However, two people who are geographically far apart are definitely not related by blood, and the farther away they are, the greater the difference in gene arrangement and structure. When such two people are combined and the genes are paired, even if one of them has recessive harmful genes, it will not be shown, and it will even be gradually eliminated in the process.

Moreover, the diversity of genes will also make their offspring have stronger thinking ability and higher IQ. Of course, this is compared with people who are married by close relatives. It doesn't mean that children who live far away are necessarily geniuses, just compare them with ordinary people. A child's IQ still depends on the genes of both parents. If both parents are not very smart, they will not give birth to a gifted baby, but their IQ may be slightly higher than their parents'.