Human Brain Vs Human Evolution Essay

As previously learned in class, the definition of evolution is the change in variant frequencies in a population over time. The four forces that evolution acts on are mutations, gene flow, genetic drift, and natural selection. From an evolutionary psychology perspective, the physical structure of the brain has changed over time, thus allowing humans to develop complex behavioral patterns. When comparing brains with primates, humans have a larger and heavier brain. When compared to a chimpanzee, the average adult human brain is approximately 1,352 g whereas the average adult chimpanzee brain is 384 g. Most of the growth is due to the growth of the neocortex; which is involved in higher functioning processes such as sensory perception, generation of motor commands, …show more content…
As the cerebellum began to grow, the complexity of cognition used to make tools also grew. Thus instead of having short, mode 1 tools that were very limited on the number of tasks that could be accomplished, later hominids, such as Homo heidelbergensis, possessed enough cognitive evolution to better adapt and change the way that they gathered food, by developing mode 3 tools, which were used to gather different ranges of food more efficiently. From a human behavioral ecology perspective, the growth of the brain over time can be explained by adaptive behaviors in ecological contexts. It is believed that the size of human brains increased rapidly after they began to walk upright, make tools, and start to face different environments. According to Darwinian theory, or natural selection, it would have been adaptively beneficial for humans to have larger brains so they can achieve complex thinking and analysis. Adaptive behaviors may have been induced by a change in diet, adaption to various gradients, and adaptation to environmental