Okay, humans, if we’re so smart, why do our backs hurt so much? Why do we cry? And menstruation, who thought that was a good idea?
Our existence on this planet is the product of chance, timing and a whole lot of evolutionary compromise… Alex Bezzerides knows it well. The Lewis-Clark State College biology professor is fascinated with the imperfect system that is the human body, and he explores and explains it adroitly in his fascinating, funny new book, “Evolution Gone Wrong: The curious Reasons Why Our Bodies Work (Or Don’t).”
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[Mary Elizabeth Williams:] Menstruation, pregnancy, childbirth — they’re all ridiculous. Talk to me about this, Alex. Why do we have periods?
[Bezzerides:] What I came to learn is that the process evolved in a way as a defense for women against these really hyper-aggressive, invasive fetuses humans are. We think that human fetuses are that way because they have to feed this giant, growing, nourishing brain. The only way to do that is to burrow deep inside the woman… One idea for why menstruation evolved is that the woman had to start building up her uterine lining and building up this defense even before pregnancy.