Interesting, I hope they do in-depth study. I wonder how they'd deal with this issue from that article.
"But what is also obvious is that it can be very difficult to untangle mom and dad’s contributions because they tend to track together in age. Older dads tend to have children with older moms."
"But what is also obvious is that it can be very difficult to untangle mom and dad’s contributions because they tend to track together in age. Older dads tend to have children with older moms."
It's a pretty big confounding variable.