re: #600 LudwigVanQuixote

I have heard that the early humans who came out of Africa interbred with the so called Cro-magnon in Europe.

Unfortunately, the worst sorts of people take this hypothesis and make up terrible things with it.

But this is wrong. The Cro-magnons were modern humans, homo sapiens sapiens, not Neanderthals, and not native to Europe. They are the descendants (apart from a small admixture of Neanderthal) of the humans who left Africa some 70 thousand years ago, give or take a lot…the date is up in the air.

The real story is that the humans coming out of Africa interbred, enough that the consequences are evident in our genomes today [contribution of from 1 to 4 percent], with Neanderthals, another species. Quite possibly, also with some of the various homo erectus strands that were still on the scene, outside Europe—-that research has not come in yet.

Nothing much is known about whether the Neanderthal contribution was of any advantage to those who got it. If there was a harmful component, it probably got winnowed out as evolution did its usual stuff. If there had been any exceptionally helpful component, it would have swept the genome of the population that came in contact; this doesn’t seem to have happened.