The Evolution of the Human Brain: How It Differs from Our Ancestors and Why?

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The Evolution of the Human Brain:
How it Differs From Our Ancestors and Why?
The human brain is a feat of evolution: it has allowed humans to have complex thoughts, conscience, build tools, create fires, and much more. Humans did not acquire this simply by chance. Evolution throughout our ancestral past has shaped and moulded the human mind to its state. The earliest of ancestors, including apes, had very small brains, but as evolution progressed, so too did the human brain. The rapid progression of human intelligence has been attributed to environmental changes causing humans to change with their surroundings for survival. This lead to the expansion of specific areas of the brain, vastly differing maturation of humans compared to our
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Almost ten percent of all human genes have implication in intellect function, and just a single mutation can result in a disability. Based on estimates, the occurrence of harmful mutations in the gene structure of a human is highly likely within 3000 years of modern man, and individuals may sustain two or more deleterious mutations to the intellect or emotional functions. (Crabtree, 2012)
Despite the evolutionary many benefits and gradient expenses with human intelligence, increased brain size did not occur because it was able to expand by itself. Environmental factors are what led to the evolutionary changes. A fundamental principle of evolutionary theory is that evolution is the balanced outcome between costs and benefits. Since the price of maintaining a large brain is greater, it is inherently improbably that expansion of the brain will evolve without a selection factor being adequate to overcome the high expenses. (Dunbar, 2007) There has been a strong correlation between increased temperatures in the global climate and increased endocranial volume. Over the past three million years, the average global temperature has been steadily increasing, as well as the braincase of human ancestors. Strong evidence of this is seen between the period approximately 200,000 to 800,000 years ago where the Earth’s climate experienced the greatest temperature fluctuations which
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