why some animals learn to walk minutes after they are born, but humans can take a whole year to do that?
In: Biology
It’s because the human brain has evolved to the point where it is too big to pass through birth canal. So to compensate, humans give birth earlier than other mammals. You can think of babies as actually premature. Imagine giving birth to a 2 year old!
Humans have to deliver their babies earlier in the development process than other animals due to our frames or else we wouldn’t be able to actually deliver the baby. Birthing is already hard enough for women. Imagine a toddler coming out.
Other animals are able to more easily pass more developed offspring. This is due to a combination of the way our pelvis is built in order to stand upright and also the large size of our heads that we developed to be able to hold our larger brains.
A developed infant human brain/head/skull is too big to come out of mom fully developed – it would kill her and probably lead to birth complications for the baby (evolution was before C-sections had been finessed). So we have to come out of mom half-developed, when our head is barely small enough to fit through the birth canal. At the equivalent developmental point for other animals, they would still be in the womb, developing.
Check out the new book Seven and A Half Lessons about the Brain. Animal brains don’t develop for as long as humans. So their brains are fully formed at birth.
Most replies here put the cart before the ox. It is more accurate that the fact that primates are generally atricial allowed us to supersize our heads.
What really is the cause for altiriciality is that primates are grabby, and none of them more grabby than homo sapiens. Instead of the mother and the offspring running away from a predator, the mother grabs the offspring (more often though, the offspring is attached to the mother for most of the time) and runs away. This makes it relatively unimportant for newborns to learn how to run quickly, thus this trait was lost tens of millions of years ago.
Human babies don’t need to.
A gazelle needs to know how to move with the herd or get left behind and eaten by lions.
Human babies are protected by the most vicious and effective predator the world has ever known. They don’t need to go anywhere.
Because we have a very big brain, I believe Film theory did a video on this with Baby Yoda.
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