If you're actually interested in seeing what experiments have been done and what the results are, this [1] lengthy but also plain english study provides an exce

If you're actually interested in seeing what experiments have been done and what the results are, this [1] lengthy but also plain english study provides an excellent overview of some 30 years of research results and what has been discovered. It goes over common misconceptions and arguments in quite extensive detail. IQ is dominantly heritable. The consensus on heritability (that is the percent of deviation that's explained by genetics alone) has been increasing over time. It used to be believed to be 'only' around ~60% whereas more recent results have shown it to be upwards of 80%. There are lots of strange things about IQ that can lead to poor measurement, like the fact that environmental roles can play some in young children, yet play a negligible role for people as early as adolescence. Anyhow, that paper again provides a great overview of all the issues here. If you're not up for it, Wiki has a page on it [2]. But I'm already cringing there. On the first page, I noticed some editor apparently and literally thinks regression to the mean means two people with high IQ are more likely to produce children of average IQ... Wiki has gotten really quite awful, but I digress! I'm unsure what you think you're referencing with the "Asian diaspora" or twin study data. Twin study data is conclusive on this topic. I could spam you with sources here, but seriously just searching (google scholar is a useful tool) for iq twin study will lead to a very one-sided picture. If you can provide some papers on the "Asian diaspora" that'd be appreciated, though. [1] - https://www1.udel.edu/educ/gottfredson/30years/Rushton-Jensen30years.pdf https://www1.udel.edu/educ/gottfredson/30years/Rushton-Jense... [2] - https://en.wikipedia.org/wiki/Heritability_of_IQ https://en.wikipedia.org/wiki/Heritability_of_IQ