system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do humans develop so much slower than other animals?

Like dogs/horses/cows take almost no time (weeks) to survive in the wild while a human would take years to be self sufficient in the wild.
gpt
Guys, guys, guys... it's not just brain size. You're forgetting the whole 'bipedal' thing.

Humans walk on two legs instead of four. This means that the bone structure of our hips is vastly different than most other animals. One side effect of this, is that the birth canal is much narrower for us than for other animals, and it also puts constraints on the size & position of the uterus.

As a result of these constraints, a human fetus is born when it is smaller than would be expected for closely-related animals of our size. Other animals (like horses & cows & elephants) get to gestate until they're nearly developed enough to walk. A human fetus is pushed out literally as soon as it can breathe (the hormone that initiates labor originates in the fetus' lungs). There is a recent parenting trend of saying a newborn child is in the "fourth trimester"--this perspective has some biological foundation.

In theory, humans could probably have evolved to be more self-sufficent (i.e. ambulatory) at birth despite being smaller. For example, Giant Pandas are stupid tiny when born (4oz--"the size of a stick of butter") and they're crawling around in 2-3 months, although they nurse for 18 months. Our evolutionary path developed social structures, rather than physical changes to newborns, to ensure the survival of such small infants.