Via Sully, I find this fascinating article on race and IQ. Read both pages, as the second gets into why environment is important.
I’ve been thinking about this subject for some time. Here are some random thoughts.
No matter how you twist the data, someone with a low IQ doesn’t necessarily have it because of genetics. There are a number of environmental factors that have proven connections to IQ and it seems most of them are negative (and far more prevalent among blacks). Malnutrition, illness, neglect, drugs and poor education can all drive IQ down. These are not factors passed on to children — well, at least not in their genes. The Flynn Effect, the sharp rise in western IQs over the last century, is clearly environmental (and larger than the present black-white IQ gap). Evolution doesn’t work that fast.
Moreover, the drive to reproduce and create a new generation is, in my mind, a far more important characteristic than intelligence. What good is having a high IQ if you can’t pass it on? People complain about the fertility-intelligence anti-correlation. I complain about it all the time when I go to social functions and find I am the only scientist who has spawned. But in a way, this is nature telling us something important — high intelligence (as opposed to slightly above average) isn’t a survival characteristic. If it were, high IQ people would have more kids.
Update: RPL points out, quite correctly, that the opportunity cost of having children is higher for high-IQ people. Agreed. But that opportunity cost is lower than it has ever been. And the reason for not having kids that I hear most often has nothing to do with career, but lifestyle.
It would be interesting to compare the career achievement of high-IQ people with kids to those of high-IQ people without. My personal experience is that my work ethic improved after having a kid. Others’ mileage my vary.
Update: One thing I thought I’d ad: IQ can only get you so far. I work in a high-IQ profession and it’s my experience that smartness helps, but had work and perseverance are the deciding factors. Progress in science, especially, is driven more toil than flashes of inspiration. What was it Edison said about invention?
Always remember, Charles Darwin didn’t have a high IQ. And he glimpsed the inner workings of the world — through years and years of hard work.