Further, as I understand it, nurture are huge factors, if not the biggest. Poverty, abuse, pollution, zip code, etc.

Noob me: Sure, some fraction of IQ is hereditary for individuals. But there's no correlation between hereditary (genetic) IQ and group sizes larger than families, and mosdef none at population levels.

PS- Reprehensible is the nicest adjective I can think of for those retrograde beliefs.