That is a logical possibility, yes. Imagine a town with a tradition of hitting each other on the heads with baseball bats.

In terms of differences in individuals, empirically 60%-80% appears to be genetic: https://en.wikipedia.org/wiki/Heritability_of_IQ

But the individual is never the focus on these arguments. You refer to countries having higher intelligence. We have many towns where I live where education and smarts are mocked. The countries with higher intelligence revere education and ensure children are cared for. And the genetic component of the principal factor of taking intelligence tests as children could easily be weird traits like a slower rate of neuronal death during adolescence or not having a fear. Also most of the tests can't actually get a good number for individual variance due to the many subgroups with many related environmental factors. So you have a mathematical artifact of tests with poor experimental conditions getting .6 to .8 hereditabilty. And then you claim we can make a population that is multipme standard deviations away from the biological norms? It seems like a cool sci-fi stretch more not public policy ready.

How do you explain the rise in IQ scores over time ? Better genetics?

ZhuanXia never refers to countries having higher intelligence, but to them gaining higher intelligence through engineering.

True. I guess my point is that intelligence being heritable in individuals does not directlt imply that we can now use genetic techniques to improve the average IQ. Inheritability is perfectly consistent with the group average (modulo the environme t) already being as high as possible. 'Too many people with eidetic memories and the group looses topological intuition. Too many Gauss level brains and we lose the ability to do carpentry or CSS.' Maybe not but the evidence needs to be shown. Extraordinary claims and all that.

>"my point is that intelligence being heritable in individuals does not directlt imply that we can now use genetic techniques to improve the average IQ"

Depending on what you mean by 'genetic techniques', it sure does. Here's a genetic technique: Test everyone for IQ and only breed the top ten percent. Average IQ will obviously improve. This is just old fashioned selective breeding. It can be done, and in fact has been done (unintentionally) in places like Israel, where average IQ is notably higher.

Whether that would unbalance society in some sense ("lose the ability to do carpentry") is another question. I think society is actually unbalanced now; we have more stupid people than we need because new technologies have shifted the IQ demands upwards. There's no use for dumb brutes any more; we have machines to do the physical work they used to do. But we have tons of use for smarty-pants; so much that we can't get enough of them. Increasing average IQ wouldn't unbalance society; it would re-balance it to the new demands of the modern world.

Unless you think mind skills/IQ are determined by just 3 or 4 genes you will be very sad at the rate of genomic shift by selective breeding. Elsewhere people are claiming hundreds of genes. That is looking at hundreds of generations to remove the weaker version even assumong you have only a bad dominant version and a good recessive version. One generation to eliminate all the bad dominant copies for one gene. And at the cost of reduced genetic and mental variability which seems likely to reduce population fitness.

however, the current picture of vertabrate development makes it seems like such a simple genetic model for mind skill traits is hopelessly unlikely. You have weird crap like receptors being used for different functions in different areas of the brain. And they migrate / gene activate at different times of development in response to genetic expression partially determined by environmental conditions. Its a big ugly undocumented hack. I tend to assume we are all SWE but if you are not, there is human created code so unmaintainable the cost to fix/understand is easily 10x the cost to create. Evolution i guess has no reason to make it easier on gene engineers. Unless you hope the human brain ends up being kike particle physics with a few elegant math laws that make the apparent complexity simple.

That's not how selective breeding works. There's no rule where it takes one generation per gene. With a large population you can find individuals who gain many generic improvements in one generation. With sexual reproduction you can combine advantageous gene lines. Finally, note that we're starting with a huge amount of diversity so we don't need to create new genes, just select the best ones we already have.

Or environmental lead exposure? Or a tradition of reading to children at a young age?