Did a rapidly changing climate make early humans smarter?

A new study points out that a constantly shifting environment may have forced us to get smart or die trying

Africa's Olduvai Gorge: The birthplace of humankind?
(Image credit: CC BY: Noel Feans)

The question: Scientists are always on the hunt for clues in our evolutionary history that might help explain why we have such highly advanced brains. Some have pointed to the advent of cooked food as a tipping point, giving our brains the nutrients and proteins needed to grow. Others say it's the invention of agriculture, which diverted our attention away from merely surviving to more intellectual pursuits. Now, scientists from Penn State University think the rapidly fluctuating climate some 2 million years ago may have forced homo erectus — a direct ancestor of modern humans — to change their behavior as they migrated from the forest to the dry, flat grasslands and back again. Did climate change spark a period of major intelligence gains?

How it was tested: Researchers focused on a region in Africa called the Olduvai Gorge — an area where humankind is thought to have originated. Scientists believed that the area began drying up 3 million years ago in something they call the "Great Drying," robbing the area of trees and other lush plant life. Biochemists used techniques like gas chromatography and mass spectrometry to analyze carbon isotopes from wax leaf samples. With that data, they were able to create a timeline for the amount of vegetation in the area over a period of 200,000 years.

Subscribe to The Week

Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

SUBSCRIBE & SAVE
https://cdn.mos.cms.futurecdn.net/flexiimages/jacafc5zvs1692883516.jpg

Sign up for The Week's Free Newsletters

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

Sign up
To continue reading this article...
Continue reading this article and get limited website access each month.
Get unlimited website access, exclusive newsletters plus much more.
Cancel or pause at any time.
Already a subscriber to The Week?
Not sure which email you used for your subscription? Contact us
Chris Gayomali is the science and technology editor for TheWeek.com. Previously, he was a tech reporter at TIME. His work has also appeared in Men's Journal, Esquire, and The Atlantic, among other places. Follow him on Twitter and Facebook.