I see how other animals stand and walk literally 10 minutes after they’re born but as babies all we do is cry and eat, why aren’t we like other animals?
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It’s a biological payoff for two things we do that others don’t; walk upright and having larger brains.
Tldr: our species made a compromise by having our babies at a more immature stage and needing more care so we can go on to walk upright and be more intelligent than other species when we grow up. Otherwise most women would die in childbirth when their bodies split out delivering a two year old!
Since we walk upright our pelvises are shaped differently that other mammals, and even different from other primates (similar general appearance but ours are proportionally narrower). Our pelvises are narrower so babies need to be born at an earlier stage of development that other species so that the head doesn’t get stuck.
The other part is that, compared to our body size, we have large heads because we have larger brains that other species. And they will continue to grow relatively rapidly in the first few years of life. If you look at World Health Organisation growth charts the head circumference section only goes up to 2 years of age, as by that point your head isn’t going to get that much. Look at some 2-3 year olds head sizes and think about pushing that through a north canal.
Because of the combination of having bigger brains but proportionally narrower pelvises than other species, evolution compromised and we give birth to offspring at a more immature stage than other mammals.
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