Eve: How the Female Body Drove 200 Million Years of Human Evolution

by Cat Bohannon

Instead of twisty trapdoor vaginas, we now have the Pill and the diaphragm. Instead of the Bruce effect, we have methotrexate and misoprostol. Instead of waiting for a less dangerous birth canal to evolve, we have midwives who help our newborns squeeze through the gauntlet and the miracle of modern C-sections.[*37] When, in other species, physiological evolution would have created a newly evolved feature to enable female reproductive choice, hominins used behavioral innovations instead—some of them social and others involving new tools and pharmaceuticals. That control we have over the most powerful levers of our evolutionary fitness got us to where we are today. It allowed the early human population to finally explode, expanding into nearly every ecological niche our ancestors stumbled upon. It also improved the survival rates of every pregnant female with a too-narrow pelvis and a greedy placenta.