ugh. again, the answer is that the mutation happened in northern europe and moved south with population displacement.

the error in thinking is deeper, though. it's only a contradiction if you take the ridiculous position that every trait is the result of natural selection.

again: that would be a world that was practically created. if you're going to substitute natural selection for god and ignore chance and randomness, you're not really taking the religion hat off, you're just giving it a different name.

biologists need to get it through their skulls that genetic drift is a valid explanation.

the way they should look at it is to assume genetic drift unless evidence exists to justify natural selection. that is, genetic drift ought to be the null hypothesis, and ought to be only overturned under the presence of sufficient evidence.

*that* is a naturalist position.

his hypothesis, though, is worthwhile. i don't, however, see why it should apply specifically to the south.

http://phys.org/news/2014-01-calcium-absorption-evolution-digestion-europeans.html