[hn_throwaway_99]

> Correlation does not equal causation.

The fact that you have said this makes me think you have misunderstood my point.

I am not arguing that genetic differences are responsible for any change over the past couple generations. I am strongly arguing that there is now an enormous new selection pressure, i.e. a new factor that strongly affects fertility rates, and over time (and, perhaps a very long time) that genetic inheritance will respond to that selection pressure. That is inherently how evolution works.

People love to say "correlation is not causation", but all evolution really works with in the first place is correlation. That is, the environment changes, and then organisms that happen, through "the genetic lottery", to not be able to reproduce in that new environment are outcompeted by those organisms that do. My argument is that the environment that determines whether humans reproduce has changed drastically over the past ~100 years or so, and that this will affect which genes are likely to be more prevalent in the future. I am not arguing this genetic change has already happened.