WTF are you going on about?
that at a time (not that long ago) when europe was under developed, when europeans were filthy savages that shat in the streets and tortured each other, when the IslamIC African Moors who ruled Spain were pursuing art, music, philosophy, and science --- that at a time like this, i would have liked to see the results of a similar study comparing the average mental capacity of different racial groups.
my point being, just in case anyone a bit thick in the head has any problems figuring it out (or more likely intentionally misinterpret the above), that europeans would have undoubtedly scored much lower in such a test during that time period.
and this demonstrates that
1. the results of such tests have no bearing what so EVER on any geneticist model, and
2. has
everything to do with environment, culture, circumstance, and the conceit/prejudice of those who happen to have the upper hand (just so happens those conducting the tests).
500 years ago most Europeans were agricultural labourers, so of course they were bound to be darker-skinned than modern Europeans.
surely that is one factor. but the study i heard about had to do with a particular freakish mutation which made europeans so pale, besides the effects of the sun.