If humans and chimpanzees evolved from the same species, then what allowed us to have a higher intelligence level? How did humans become so smart?

As homo sapiens evolved into advanced societies, the complexity of our brains also increased to match the intelligence level required for innovation and daily tasks.

Across the first two-thirds of human history, our brains were easily comparable to that of a chimpanzee, both in size and neural connections. However, the human brain has nearly tripled in size over the past seven million years, most of the increase in size occurring over the past two million years. As this growth occurred, our fun-loving cousins stayed pretty much the same. But why?

The reason for this is actually quite simple. Humans' and chimps' genes split from the same species about five to seven million years ago. Since then, only humans have evolved into the machine-like masterminds that have forever changed the world.

When our genes split, humans' brains (overtime) became larger and more complex. To this day, the average chimpanzee has the basic intelligence level of a four-year-old human. Therefore, you're probably wondering why humans are so much smarter.

Most research shows that this tends to depend on some sort of mathematical law having to do with the ratio of brain size and intelligence level. "Species with bigger-than-predicted brains would be smarter than average, while those with smaller-than-predicted brains would be dumber.", says Dutch anatomist, Eugène Dubois. However, this isn't always accurate. Let's use the classic Tyrannosaurus Rex as an example. I'm sure you've heard at least a million times that the T-Rex has a brain the size of a walnut. Although, recent research suggests that this isn't actually true. Some paleontologists even argue that this so-called "stupid" dinosaur has a similar level of intelligence to a chimp.

So, what is this implying? The answer would be that basically nothing - in terms of an exact science - determines the size of an animal's brain. Now that we know why humans are so smart, what's left is how it happened.

As our genes split from chimps, humans started to develop more white matter in their temporal cortex, the lower/bottom-front part of the brain. This meant that we could produce more connections between the nerve cells, therefore, improving overall intelligence and memory ability. A coincidental study also proves that as our brains grew, so did the temperatures. According to the Smithsonian Institute of Natural History, "Human brain size evolved most rapidly during a time of dramatic climate change. Larger, more complex brains enabled early humans of this time period to interact with each other and with their surroundings in new and different ways. As the environment became more unpredictable, bigger brains helped our ancestors survive." Could this be the reason for the excessive growth in size and intelligence that overcame our brains?

Interesting enough, the human brain, after undergoing a series of developments and changes in size, has shrunk slightly over the past 10,000 years. John Hawks, a professor of anthropology at the University of Wisconsin–Madison states that "With some evolutionary irony, the past 10,000 years of human existence actually shrank our brains. Limited nutrition in agricultural populations may have been an important driver of this trend." It's hard to believe, especially considering the advancements we are making in technology day after day. However, it has the world wondering "Could this reduction be continuous?" What would happen if humans went back to being average?

Over the past seven million years, our brains have tripled in size, leaving behind our lower-level cousins, the chimps. As we became smarter, so did the world around us. Climate change, new neural connections, and split genes all contribute to the fact. Artificial intelligence, virtual reality, and much more is beginning to replace and perfect what the human brain can't. Could this increase in smart tech be responsible for the decrease occurring in our brains? Is it possible that what we thought was the missing piece of a superior future awaiting us could really be the downfall of our society?

And, in an ultimate conclusion, was this change in size and intelligence of the human brain truly for the best?