Childhood for humans is considerably a lot longer than for other mammals including our closest living primate relatives. There is a long period of immaturity in humans even when taking into consideration our relatively long lifespans. However, stretching out the maturation may have given humans a unique evolutionary advantage. Humans and chimpanzees split off between six to seven million years ago and have been evolving separately ever since then. Early human fossils showed that humans had short growth periods which are a lot more similar to chimpanzees nowadays then modern-day humans. There is slow maturation in children nowadays that is linked to human’s emergence in society, this long period of maturation allows for an extended period of education. Humans are able to learn more and develop their brains better than other primates allowing them to “live slow and grow old.”
Comments
Suggestion
I would re-read some of your sentences and try to make them less wordy. It makes the flow of the paragraph less smooth. For example, your first sentence reads, "Childhood for humans is considerably a lot longer than for other mammals including our closest living primate relatives." Where it could say something such as, "Childhood for humans is considerably longer than for other mammals including our closest living primate relatives."
suggestion
I'm not sure why "live slow and grow old" is in quotations, is it referencing something? If it is, maybe you should remark where that came from.
Rewording
It's good to add the "when" at the beginning of the sentence, like "nowadays, ..." instead of saying "nowadays" in the middle of a sentence