If you compare the human brain with that of other animals, you will see it is significantly bigger. For quite a long time, researchers have been debating the origin of its size and of human intelligence and offered mainly social explanations. Now, a scientific team from St. Andrews University in Scotland came up with a new explanation. There might have been ecological factors like difficulties in finding food and harsh weather that prompted the human brain to evolve.
Why is the human brain bigger than that of other animals?
As the first early humans emerged, they also evolved a brain that had about triple the size of that of Australopithecus afarensis, one of our ancestors. Scientists regarded this change as really interesting and started debating on possible causes for it. They offered three hypotheses: the changes have been driven by social factors, the environment played a role in it, or the human brain evolved as we started eating meat.
Of course, given the intelligence of humans, scientists preferred the social explanation and said our brain got bigger when we faced social challenges. However, there were others who were a bit more skeptical, so Scottish researchers decided to find the truth. To do it, they ran a few mathematical simulations of how the human brain evolved throughout millions of years.
A harsh environment is the biggest contribution to a bigger brain
They took all three hypotheses into consideration and discovered more factors that prompted the growth. Whenever individuals face harsh environmental conditions and are exposed to conflict but also to cooperation, they start developing their brain. However, only one of these has a main contribution, and that is the environmental factor.
When the early humans started migrating further away from the equator, they had to face less friendly conditions. The weather got less warm, and they suddenly found less food than before. As a result, the human brain started increasing in size. However, there was one condition for the brain to get bigger. Each individual need to acquire new skills and improve its capacity throughout their young years.
The study on the wonders of the human brain was published in the journal Nature.
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