Chimpanzees are intelligent animals capable of working with tools and solving problems but regardless of how smart the chimps are, their brain power pales when compared to that of humans.
Several factors make the human brain superior to that of chimps but findings of a new research reveal this also has something to do with our brains being more responsive to environmental changes compared with the chimps' brains.
In a new study published in the in the journal Proceedings of the National Academy of Sciences on Nov. 16, researchers conducted an analysis of 218 human brains and 206 chimpanzee brains and found that compared to the chimp's brain, the human brain exhibits more plasticity, or the brain's tendency to change in structure, size and shape in response to external factors.
To determine how genetics may shape the brain, the researchers examined the brains of the two species using MRI scans. The researchers likewise used information from detailed family trees of chimps to measure the similarity in brains of genetically related individuals. MRI scans from related humans such as twins were also intentionally chosen for the study.
The findings revealed that closely related individuals in both species have similar brain volumes but this does not hold true in terms of brain structure.
The brain structure in chimps was mostly inherited just like with the brain size but the structure of the human brain was less influenced by genes, which means that the human brain is more susceptible to external influences such as experience, environment and social interactions.
"We found that the anatomy of the chimpanzee brain is more strongly controlled by genes than that of human brains, suggesting the human brain is extensively shaped by its environment no matter its genetics," said study lead author Aida Gómez-Robles, an anthropologist at George Washington University.
The team said that humans being born with underdeveloped brains may have contributed to increased neural plasticity. Having less developed brains at birth may render humans more helpless but this allowed for more postnatal brain growth that can be largely influenced by the outside world.
The researchers said that this increase in plasticity is likely one of the defining features that made our hominid ancestors better than other primates in terms of intelligence.
"A major result of increased plasticity is that the development of neural circuits that underlie behavior is shaped by the environmental, social and cultural context more intensively in humans than in other primate species, thus providing an anatomical basis for behavioral and cognitive evolution," the researchers wrote in their study.
Photo: William Warby | Flickr
