Human brains make synaptic connections throughout much of childhood, and the brain’s plasticity enables humans to slowly wire them based upon experiences, contrary to how chimpanzees develop. Humans and chimpanzees share 98.8% of the same genes, but scientists have been looking for what drives the unique cognitive and social skills of humans.
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This makes perfect sense. The simian brain has to be fully developed faster so that it can make its way through the world sooner and without care of parents, otherwise certain death would occur. Humans have the advantage of being taken care of through a longer development phase thus offering the opportunity to form more and complete synaptic networks.