I hear of women in my community and across the world either having stillbirths or dying during the process of birth all the time. Why?
How can a dog or a cow give birth in the dirt and turn out fine, but if humans did the same, the mom/infant have a higher chance of dying? How can baby mice, who are similar to human babies (naked, gross, blind), survive the “newborn phase”?
And why are babies so big but useless? I understand that babies have evolved to have a soft skull to accommodate their big brain, but why don’t they have the strength to keep their head up?
In: Biology
Bipedalism (walking on two legs) forced the birth canal of hominids (human ancestors) to narrow. A feedback loop between improved cognitive abilities and being better adapted to exploit the environment caused our ancestors’ brains to grow. Between the narrow birth canal and enlarged brain, human babies have to be born less mature than other apes. That’s why they aren’t able to hold themselves up quickly like a baby chimpanzee can. Our social adaptations mean that mature humans can continue “gestating” babies outside the womb. So, it isn’t a perfect system, but it is successful enough (aka highly successful) that despite the issues and limitations it wasn’t ever selected against evolutionarily.
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