This 2015 George Washington study compared human and chimpanzee brain attributes to find:
“The morphology of the human cerebral cortex is substantially less genetically heritable than in chimpanzees and therefore is more responsive to molding by environmental influences.”
From the news coverage:
“We found that the anatomy of the chimpanzee brain is more strongly controlled by genes than that of human brains, suggesting that the human brain is extensively shaped by its environment no matter its genetics.
Though our findings suggest that the increased plasticity found in human brains has many benefits for adaptation, it is also possible that it makes our brain more vulnerable to many human-specific neurodegenerative and neurodevelopment disorders.”
The study demonstrated an aspect of how natural selection of species leading to Homo sapiens – after humans and chimpanzees shared a common ancestor – favored our increased capacity to adapt to our environments.
http://www.pnas.org/content/112/48/14799.full “Relaxed genetic control of cortical organization in human brains compared with chimpanzees”