“Remember how heritability works. If environments improve, genetics will explain more and more of variance. It’s Liebig’s barrel. Shared-environment in the USA is very small.”
I’m not sure that this can be assumed true (and forgive me if the point is addressed elsewhere. I have mostly only read this comment). If someone is phenylketoneuric, improved environment will eliminate what would otherwise be a profound difference between them and their cohort.
Harsh environments tend to accentuate differences, including genetic differences. There’s been some push to put lab animals through more rigorous trials to better observe subtle differences between them.
If genetic susceptibilities to environmental insult explains many differences between populations then it’s entirely possible for environments which address those susceptibilities to reduce the apparent portion of differences which are viewed as “genetic.”
We can’t begin to predict whether improved environment will increase or decrease the differences due to genetic variance until we address the specific mechanisms underlying that variance. (And, in a kind of Catch-22 once we understand the underlying mechanisms we’re very close to addressing the issue through some kind of direct intervention (like genetic editing of embryos.) )
This makes prediction even harder, since self-modifying systems are hell to reliably forecast till they reach some kind of equilibrium.
I’m not sure that this can be assumed true (and forgive me if the point is addressed elsewhere. I have mostly only read this comment). If someone is phenylketoneuric, improved environment will eliminate what would otherwise be a profound difference between them and their cohort.
Harsh environments tend to accentuate differences, including genetic differences. There’s been some push to put lab animals through more rigorous trials to better observe subtle differences between them.
If genetic susceptibilities to environmental insult explains many differences between populations then it’s entirely possible for environments which address those susceptibilities to reduce the apparent portion of differences which are viewed as “genetic.”
We can’t begin to predict whether improved environment will increase or decrease the differences due to genetic variance until we address the specific mechanisms underlying that variance. (And, in a kind of Catch-22 once we understand the underlying mechanisms we’re very close to addressing the issue through some kind of direct intervention (like genetic editing of embryos.) )
This makes prediction even harder, since self-modifying systems are hell to reliably forecast till they reach some kind of equilibrium.