How can research claim the genetic component of IQ is so high when there are so many environmental variables that have to be accounted for in order for the genetic component to even be able to manifest?

For example, if two identical twins are separated at birth. If one is raised in an educationally rich and nurturing environment and the other is raised in a horribly abusive and neglectful environment, then I am not sure the two would probably score the similarly on any given IQ test despite their genetic commonalities. Meanwhile, I imagine things like eye color, hair color, etc. which have a strong genetic component would remain consistent between the two.

▲

EnPissant 3 days ago | parent [-]

Here is a twin study that places the heritability of IQ to be around 80%: https://www.cambridge.org/core/journals/twin-research-and-hu...

	▲	matthewdgreen 2 days ago \| parent [-]
		My understanding is that’s way at the upper end and there are other reputable studies (which you can search for) that put it down around 50% in twin studies, which doesn’t necessarily mean you’re going to be smart just because your parents are. But that’s irrelevant. The question being asked was: if IQ is genetic, why do we need teaching? This is like asking why you’d need ever need gas if you had extra-large fuel tank installed in your car.