The human brain is complex and more complicated than any other organ in the human body. Albert Einstein once said that if our brain were too simple, we would be too simple to analyze it (paraphrased). Although no different link was found between the size of brain and its behavior, researchers conducted a study with over 94 fossils of human species as per which, the size of the brain has increased gradually to become three times compared to our ancestors of three million ago as well as bonobos, chimpanzees which are few of our closest relatives.
Researchers conducted the study on 94 fossils belonging to 13 human species including Australopithecus who lived more than 3.2 million years ago to pre-modern Homo erectus that lived over 500,000 years ago. As per the study, human brains have been increasing consistently over a massive period of time. Earlier, assumptions were that human brains underwent evolution with step-like increments in a matter of three million years. The study published in “Proceedings of the Royal Society B” evaluated that the trend of increasing brain size came to be with the increasing population including the addition of species with a larger brain and finally extinction of the species with a smaller brain.
Andrew Du, a Ph.D. scholar at the University of Chicago stated that the brain size of a human is what makes us humans. A brain is a complex machine working our culture, language, tool making, contemplating and anticipating, and millions of other tasks. He elaborated that the size of the brain of hominids living millions of years ago was that of chimpanzees and that is why it is crucial to know what actually happened during the process.Bernard Wood of George Washington University stated an instance where there are two ways to enter into a building. One is through the ramp and another is through steps depicting the consistent and step-like increments in the brain size respectively.
During the study, researchers segregated the species based on descending order in terms of a common ancestor. Then, an average was calculated based on the data acquired which hinted towards increased in size of the brain over a matter of three million years. There are other factors too which dimmed the brain to be larger or acted as a catalyst. It is due to the introduction of new species with larger brain size, increase in population with larger brain size after evolution and finally the extinct species with smaller brain sizes.