[zozbot234]

IQ results are meaningful, but there's nothing 'biological' about them. Variation in IQ is heavily influenced by all sorts of social factors, and variation across social groups even comes with difficulties in measurement. The meme that 'IQ is biological' is just that, a baseless urban legend.

[SamReidHughes]

Don't be ridiculous. Performance on IQ tests is highly heritable and is also severely affected by metabolic disorders, childhood iodine deficiency, and sleep deprivation. That's biological.

[centimeter]

It's funny when people are so uniformly wrong but write with such confident language. Most estimates based on twin and sibling studies place 60-80% of variance in intelligence as genetically heritable, with a single-digit percentage of adult IQ attributable to known environmental factors.

[zozbot234]

Twins-vs.-siblings studies are irrelevant to variation across large social groups. There's no way anyone can "write with confident language" about any of that variation being biological in nature, given that the social milieus are so starkly different.

[zo1]

Twin vs sibling studies aim at quantifying what effect genetics has on IQ rather than environmental conditions. If there are hereditary components to it, then they most certainly can be mapped to some extent across population groups, as have a lot of other "traits". There are only so many ways to slice this, but it is unfortunately a delicate topic.

[diffrinse]

Question, are the studies telling us IQ is heritable or telling us a dumb person can't have smart kids?