This is a very complex question, but let’s go at it another way. The races that we experience today didn’t really come from Adam and Eve. You know why? Because everybody on the face of the earth got drowned, except for Noah and his three sons, and their wives. So, all the races came from Noah and Mrs. Noah, and the three little junior Noahs: Shem, Ham, and Japheth. And they were all, you remember, rescued in the flood, and they came back and began to populate the earth.
The best we can tell, Shem located with his people in the Middle East, and are the Semites: Jews and Arabic people. It’s a huge part of the world--huge population. Ham, in most studies (and I’m reflecting back a few years in reading things like Oliver Buswell III, and others who dealt with these issues, and some other books on the tables of nations), it seems that Ham became a more servile people and may have moved south and wound up in Africa. The descendants of Ham and Japheth seem to have colonized Europe. It’s very difficult to know all of that specifically, but they obviously, through the years, adapted themselves to their areas. They of course began to develop and all the races eventually came.
But, apart from what might be the scientific and historical explanation, is the statement of Acts 17, where it says, “The God who made the world and all things in it, since He is Lord of heaven and earth, does not dwell in temples made with hands; neither is He served by human hands, as though He have need of anything; He made, from one, every nation.” So, that’s the best answer. Acts 17, verse 26, God, from Noah and Mrs. Noah and Shem, Ham, and Japheth, created the nations.
Now, one major component in that happened at the Tower of Babel of course, where God scattered all the nations all over the face of the earth and changed their languages. So, the best answer is right there in Acts 17--God did it. And God sort of tweaked their ears and tweaked their eyes, and their nose, and the color of the skin, and all those genetic unique things, in His creative power, through the process of providential genetics, to create all the different races.