Indeed you're right about running, Chuck, despite popular belief, men also are on average faster at ultramarathons as well, despite women sometimes winning them. This article explains it quite well:
https://trainright.com/women-faster-than-men-ultramarathon/
The female advantage in endurance is on a like-for-like level, so pound for pound. That's why women get closer the longer the race, but never fully close the gap because they can't match men for size.
Women also have an advantage, like said in the post, at the non-maximal output level. So, walking versus trying to set as fast a time as you can. Here women suffer less fatigue than men, so recover faster, even if carrying a child.
Also, when it comes to swimming, women come out on top at long distances. This is because their greater fat levels provide greater buoyancy and body temperature control.
So, the female endurance advantage when it comes to staying power, is complex, but very much real.
I'll be writing a post about the swimming advantage in the not too distant future!
Hope that all makes sense, thanks for the comment!