Much of the recent physical morphological change in people's bodies is due to C-section selection.

C-sections are performed on women with tall narrow "anthropoid" hips. These hips are built for narrower heads with smaller brains. They are also more common on African women, and least common among Asian.

When a woman with anthro hips has kids with a big-brained man, the baby cannot make it out of her pelvis due to shape mismatch. Thus, the woman dies in childbirth, and the baby often dies too.

C-sections disrupt this natural selection process, enabling these smaller-brained, anthro-hipped women to be several times more fertile than usual. Almost everybody survives a C-section since antibiotics came out.

The effect is that we get more small-brain and narrow-hip genes in our population. And that is exactly what we see.