3. A too-narrow pelvis Problem: Childbirth hurts. And to add insult to injury, the width of a woman's pelvis hasn't changed for some 200,000 years, keeping our brains from growing larger. Fix: Sure, you could stretch out the pelvis, Latimer says, but technologists may already be onto a better solution. "I would bet that in 10,000 years, or even in 1,000 years, no woman in the developed world will deliver naturally. A clinic will combine the sperm and egg, and you'll come by and pick up the kid."