Yet our physiology is tuned to become parents at 16 rather than 40.

I think nature doesn't care whether it's easier or better or whatever. It only cares for _more_ children to survive until their own time to have children.

you just restated what i said. perhaps i could have been more clear.

by whatever mechanism, humans can breed at a much younger age than they can feasibly take care of their offspring. Up until maybe 75-100 years ago, "it takes a village" wasn't just a trite canard, it was actually how you raised children. I just finished watching a youtuber explain that raising children after having had to move away from your extended family because of affordability is suck and "maybe that's why young people are waiting to have kids, because there's no village anymore."