I'm asking if there is a rational non-meta reason to believe they do "stop at the neck" even if we throw away all the IQ/nations data.

Of course there are. The standard argument is that the history of human evolution suggests that increased intelligence and favorable personality traits were strongly selected for, and traits which are strongly selected tend to reach fixation rather quickly.

But then the difference in intelligence would be almost completely shared + nonshared environment. And twin studies suggest it's very inheritable. It also seems to be a polygenic trait, so there can be quite a lot of new mutations there that haven't yet reached fixation even if it's strongly selected for.

Open thread, Apr. 18 - Apr. 24, 2016

by MrMind 1 min read18th Apr 2016176 comments

2


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