But east-Asians do better than Europeans, and Europeans better than others, on average. The argument is that north-east-Asians have the highest IQ due to selective pressure in an Ice Age high latitude arctic environment, Europeans next highest due to Ice Age sub-arctic arboreal environment, etc. Like I said, I'm unconvinced as I don't think the evidence is strong for all significant human evolution being back in the Ice Age.
Your sources are?
If it's Phillipe Rushton or anyone else with Pioneer Fund backing, you've essentially been duped by racists -- the Pioneer Fund is basically a well-heeled hate group. Since this is basically where these assertions come from, the chances are high that you've made this mistake.