Prehistoric Conflict May Have Spurred the Evolution of Humans' Large Brains

Prehistoric conflict may have sped up technological progress and vast social and political changes, but scientists have found out that it may have also done something far more far-reaching. They've discovered that conflict might have contributed to the evolutionary emergence of humans' high intelligence and ability to work together toward common goals.

Researchers have long wondered how humans evolved high intelligence required for complex collaborative activities, despite the various costs of having a big brain. While the brain only represents about two percent of the body's weight, it uses about 20 percent of the energy consumed.

Now, researchers may have an explanation for our big brains. The scientists developed a mathematical model that offers insight into the evolutionary puzzles. More specifically, it shows that intelligence and cooperative behavior can co-evolve to solve the problem of collective action in groups and to overcome the costs of having a large brain.

Collaborative ability evolves easiest if there is direct conflict or warfare between groups. In contrast, collective activities, such as defending against predators or hunting for food, are less likely to result in significant increases in collaborative abilities. This means that human conflict helped spur the evolution of a larger brain.

"Our ability to effectively collaborate with others is largely responsible for what our species came to be," said Sergey Gavrilets, one of the researchers, in a news release. "The big question is how this ability first evolved when there are large metabolic and physiological costs related to human brain size and when collaboration can be easily undermined by free riders. The model offers an answer which emphasized the role of between-group conflicts in shaping unique human features."

The findings reveal that collaboration and the evolution of large brains could be linked. Not only that, but conflict could have sped up this process in humans. The findings lend further insight into human evolution and how society itself came to be.

The findings are published in the Journal of the Royal Society Interface.

For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).