Honest question that keeps bothering me.
In the absence of reasonably strong natural selection pressure to select for IQ, how could IQ not be falling over time?
replies(5):
In the absence of reasonably strong natural selection pressure to select for IQ, how could IQ not be falling over time?
Academics often stereotype “jocks” and high social status seekers as stupid. However, it often requires brains to succeed in sports and social interactions. But it is technically difficult to measure high “intuition”. I know some very very smart people that fail academically (I know they are smart because I see them achieve seemingly impossible outcomes, not because I have their skills). I strongly suspect that selecting for high non-academic skills will select for general intelligence. If one lacks skill X (e.g. the stereotypical nerd[1] with low social skills) then one usually lacks the ability to recognise people that are highly skilled in skill X (and worse often assumes the skill is useless or denigrates those with the skill or thinks they could be highly skilled if they wanted to).
There could be bubbles of selection pressure - subgroups where high IQ leads to having more kids. So long as the subgroup intermingles, then there is a population level pressure for higher intellect.
It is possible that unsmart people remove themselves from the gene pool before reproduction, or unsmart people reproduce less.
One or two outlier smart men that have thousands of children could have a massive selection pressure. Are we not all descended from Ghengis Khan?
Smartness has thousands of factors, and selection pressure on some hidden factors could easily have an outcome on general intelligence.
[1] Counterpoint “Being smart seems to make you unpopular” implies popular people are not smart: http://www.paulgraham.com/nerds.html