At least on a country level, the correlation between IQ and fertility is strongly negative:
Worth noting that, within countries, this varies by culture. I don’t have the graph on hand, but, for males, the fertility/IQ slope inverts depending on American political affiliation[1]. It’s negative for women either way, unfortunately, but the slope is a lot flatter if they’re Republican, to the point where I’d expect the positive correlation for men to cancel it out and yield a positive overall coefficient.
I would expect similar splits within other countries, and within America along other axes. For example, some religious groups and regional subcultures would probably demonstrate a positive IQ/fertility curve that dominates political affiliation.
Moreover, they don’t include South Korea, which has seen massive decline in fertility
South Korea has started to go back up. I think “let’s be the ones who show up to the future, whatever it takes” is a really romantic idea, and apparently some proportion of Koreans do too. A massive selection effect for romanticism may not be the primary effect of this bottleneck, but it does feel like a silver lining.
Intuitively, smarter people are more agentic, and thus better at putting their stated values into practice. A clever Republican will find ways to make pro-natalism work, and likewise a clever Democrat will find ways to avoid unplanned pregnancies. Your reasoning on breadwinners also tracks with this data, though.
Worth noting that, within countries, this varies by culture. I don’t have the graph on hand, but, for males, the fertility/IQ slope inverts depending on American political affiliation[1]. It’s negative for women either way, unfortunately, but the slope is a lot flatter if they’re Republican, to the point where I’d expect the positive correlation for men to cancel it out and yield a positive overall coefficient.
I would expect similar splits within other countries, and within America along other axes. For example, some religious groups and regional subcultures would probably demonstrate a positive IQ/fertility curve that dominates political affiliation.
South Korea has started to go back up. I think “let’s be the ones who show up to the future, whatever it takes” is a really romantic idea, and apparently some proportion of Koreans do too. A massive selection effect for romanticism may not be the primary effect of this bottleneck, but it does feel like a silver lining.
Intuitively, smarter people are more agentic, and thus better at putting their stated values into practice. A clever Republican will find ways to make pro-natalism work, and likewise a clever Democrat will find ways to avoid unplanned pregnancies. Your reasoning on breadwinners also tracks with this data, though.