eli5: why do human babies take so long to mature and develop whilst most animal babies can do things on their own very shortly after birth?
In: Biology
Some animals have lots and lots of babies all at once, while others have just a few but take really good care of them. These two ways of raising young are called different life strategies.
The first strategy is used by animals like frogs and flies. These animals have a lot of babies at one time because they know that many of them won’t survive. For example, a frog will lay hundreds of eggs in a pond, and many tadpoles will be eaten by bigger animals. But, because there are so many, some will grow up into frogs. These animals don’t take care of their babies after they are born—they just lay the eggs and hope for the best. They usually grow up quickly and don’t live very long. This way of raising babies is all about having lots of young at once, knowing that only some will make it.
The second strategy is different. Animals like elephants and humans have fewer babies, but they take really good care of them. An elephant might only have one baby at a time, and that baby stays with its mother for a long time, learning how to find food and stay safe. Humans do the same thing, putting a lot of effort into making sure their children grow up healthy and safe. Animals that use this strategy usually grow more slowly and live longer lives. This way is all about focusing on just a few babies and making sure each one has the best chance to grow up well.
Humans’ biggest strength is our brain, which, for being so smart, has to be big. So big that, were it to mature any further before birth, we could not make it out of our mothers.
Solution: Human babies are actually purposefully born rather underdeveloped relative to other animals.
Human babies take comparable time to develop as chimpanzees, that is withuth compensating for the difference i how long we live. They remain in practical constant contact with their mother the first year, by two years they start to move out of arms reach from their mother and by four to six they are weaned and infancy ends. They remain juveniles until they are nine years old. This is not that different to humans
It is herd animals that will need to move with the herd directly after they are born that evolve to do that, horses for example when it takes hours for a foal to walk.
If you look at predators the young are typically a lot more helpless at birth, they can hide or the mother protect them. Cats and dogs are examples of this and it takes a couple of weeks for them to walk.
Humans and other primates have offspring that take a very long time to move by themselves safely but at the same time the mother has the ability to carry them with their hands
One of the reasons is that primates and specially humans have huge brains that take a long time to develop, To develop longer in the mother the head and baby would need to be larger and birth is hard enough as it is for humans because if how the body layout with bones.
Humans and other primates have evolved to use intelligence that takes a long time to develop at a way to survive, a drawback is that it results in infants that the mother needs to take care of for a long time. It is the large skull and wide shoulders that is problematic to pass through the birth canal.
Our survival strategy is to have big brains and rely on our social group to keep the kids alive long enough that they can fully brain.
Most animals survival strategy is “welcome to the world, don’t get eaten, it’s time to run for the life you just got cause a predator watched you be born. ”
To do the same as a human you’d have to give birth to like a 2 year old or something. We’d need hips that are wildly wider than humans have today to evolve like that. WILDLY wider.
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