I would imagine the argument is as follows: Climate, along with dozens of other factors, produced variations in human traits. Some of them, like skin color, he

I would imagine the argument is as follows: Climate, along with dozens of other factors, produced variations in human traits. Some of them, like skin color, height, etc. are obvious to everyone. Others, including intelligence, are not so obvious. But the idea that IQ is inheritable and variable between ethnicities is not too terribly controversial, even though it is politically taboo to mention. Thus, you'd find that some groups are more likely to dominate fields than others (due to nature) and not 100% because of societal differences (i.e. nurture). So the actual question for a society in a competitive global economy to ask is what proportion of limited resources are used to help those in the rear catch up vs what proportion is used to push the most gifted farther ahead.