What is population genetics and how does it relate to evolution?

What Causes Variety in Races?
When the sperm cell from a man unites with the egg cell of a woman, a new human life is conceived even though the parents are of different races. Yet within that very small cell are thousands of genes, the transmitters of hereditary traits. These traits reflect characteristics seen in the parents or other ancestors.
The genetic makeup of the first man, Adam, was such that extensive variety could develop among his offspring—in such things as skin color, hair color and texture, body size and facial characteristics. This variety was increased by language and geographical differences.
Concerning geographical isolation the Encyclopedia Americana explains: “When lands inhabited by two or more populations are separated by seas, mountain ranges, deserts, or other obstacles to travel, the members of these populations are perforce confined to their respective territories. . . . races will be separated by gene frequency gaps corresponding to the geographical boundaries. . . . this condition is approached in Africa, where the Sahara Desert forms a boundary between the European (white) and the African (Negro) races. The Sahara is very sparsely inhabited and So although the Bible was not written by scientists, yet it was correct in stating that“difficult for man to traverse; it constitutes an isolating agent of long standing.” Therefore genetics, language and geographical barriers help to explain why distinctive racial groups appear in all parts of the earth. So although the Bible was not written by scientists, yet it was correct in stating that “God . . . made out of one man every nation of men, to dwell upon the entire surface of the earth.”—Acts 17:24, 26. Remember evolution is a theory not facts. The question you asked you need to do research for each country.
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