We have all heard that humans are better than other animals because of our big brains, but is that really true?
Mammals have an average brain size of 12 cubic inches, while our human brains have an average size of 73-85 cubic inches (and even, our past ancestors like the Neanderthals had bigger brains). However, modern Homo sapiens had more advanced cognitive abilities even when they were living with the neanderthals. If the hypothesis that a bigger brain leads to a higher intelligence were assumed to be true, the feline family and frogs would also be able to help us do our calculus homework and go to space in rockets. The real reason why huge brains are so rare in the animal kingdom is because they are a major strain on the body.
First of all, a brain is a hassle to carry around, especially because of its surrounding giant skull, and it is even more difficult to fuel. The brain is approximately 2% to 3% of the total body weight for Homo sapiens, yet despite this, it takes up 25% of the body’s energy at rest. In comparison, other apes’ brains only take up 8% of their rest-time energy.
For archaic humans, this meant that they would have to spend more time searching for food to fuel their larger sized brains, and as a result, their muscles atrophied due to energy being divided from biceps to neurons. This was a relatively good survival strategy in the wild, but it still meant that humans were much weaker than their ape counterparts.
Nowadays, our brains have been able to produce cars and guns that have allowed us to overcome and evade chimps and apes who can overpower us in physical combat. So, although it took about a few thousands years before our first Cognitive Revolution, today our extraordinarily large brains have certainly paid off in bettering our survival and life quality.
References
Harari, Y. N. (2018). Sapiens: A brief history of humankind. Harper Perennial.
Comments