I find it interesting that so many acknowledge that genetic factors account for a wide range of characteristics among humans and their diverse races, such as athletic ability, hair color, sweat-gland concentration, body-shape, height etc, but that somehow genetics mysteriously plays no role in intelligence.
It is silly to believe that we are all equal mentally. That we are unequal physically is a readily noted fact-- no one has any qualms about saying that an African makes a better basketball player than a Caucasian. That we are unequal mentally is a hot potato that no one wants to touch because being labeled a "racist" ruins lives, ruins careers, and ruins your own self image.
So don't be ridiculous. Various environments and their obstacles forced some populations to strain their bodies and their minds more than say a flat savanna where animals, water, and vegetation were all readily available. Migrate to the mountains or the tundra and suddenly the task to survive requires more mental prowess.
The answer to your question is yes.