So yes, IQ is a measure of (g) which is a synthesis of verbal(feminine bias) vs

So yes, IQ is a measure of (g) which is a synthesis of verbal(feminine bias) vs spatial(masculine bias) and it’s literally a measure of neural adaptivity. It’s really not much more than the friction or lack of it in neural connectivity.
The science is a little confusing, but it appears that even in twins it can vary quite a bit. The reason being that neural formation in utero is only probabalistic, and the first two years after birth continue the trend. So even in identical twins you can have quite a bit of variation just because they shared a womb with some variations.

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