Ken, although I distinctly recall reading about the 2% genetic diversity and also heard Genetics and Biology Professors repeat that number, I just did a little checking and found estimates ranging from .1% to over 10%. Here's a link reporting on some recent research claiming that the percentage is actually much higher than previously believed:

http://www.sciencedaily.com/releases/2006/11/061123115741.htm

No matter though. What matters is that a very small amount of genetic variation expresses itself as almost every difference we see within races or groups or individuals that cannot be attributed to physical injury or cultural upbringing. Everything from skin color to skull shape to susceptibility to Sickle Cell Anemia, Tay-Sachs disease, or BRAC II induced breast cancer is genetic. An Eskimo infant raised from birth at the equator will still have Eskimo features and a thicker layer of subcutaneous fat. Dwarf parents are much more likely to have dwarf children even though the gene for dwarfism is highly recessive. A specific number and order of gene sequences can give a person Einstein or Stephen Hawking intelligence... or the Mongoloid intelligence level of Caitlyn SKB. I have read about the Toba volcano near-extinction event, but over 2000 generations have passed since then giving ample opportunities for natural selection and natural mutation to create radical differences among the world's human population. The Toba volcano may have been the driving force behind food shortages that compelled humans to migrate to every corner of the planet. We clearly see those resulting differences, and only uninformed and agenda driven Libtards are hell bent on blaming recognition of the facts on white Republicans who create biased I.Q. Tests designed to keep people down. Generalizations are difficult because, as I pointed out earlier, one black could have abnormally high intelligence because a recessive gene from Thomas Jefferson expressed itself. It's just as possible that Thomas Jefferson inherited his intelligence from some long ago Asiatic ancestor. The opposite could also be seen when the offspring of genius level parents turns out to be well below average because there was a clinical idiot in one or both parent's ancestry. It's mathematically unlikely, but two brown haired dark skinned parents could produce a light skinned red-headed child if that recessive gene expresses itself. But it is much more likely that highly intelligent parents will produce highly intelligent offspring, and all the nurturing and teaching in the world will not turn a low intelligence baby into a Mozart or a DaVinci.

A true sign of mental illness is any gun owner who would vote for an Anti-Gunner like Joe Biden.