Cooking: The 1-Million-Year-Old Technology

An archaeological dig of a cave in South Africa provides evidence of "burning events" 600,000 years older than other conclusive sites.

RTR25DZB.jpg

Reuters

In 2009 Harvard anthropologist Richard Wrangham offered a novel theory on the evolution of humans: Homo erectus could not have evolved nearly two million years ago without consuming cooked food. No way, he argued, could raw food have provided the calories necessary for the development of the human brain. Its digestion alone requires too much energy. But cooked food changed everything. It's much easier to digest, freeing up energy to fuel our brains, not our guts. "The extra energy gave the first cooks biological advantages," he wrote. "They survived and reproduced better than before. Their genes spread. Their bodies responded by biologically adapting to cooked food, shaped by natural selection to take maximum advantage of the new diet. There were changes in anatomy, physiology, ecology, life history, psychology and society."

But there was one small problem with Wrangham's theory: Cooking food requires fire, and the oldest unequivocal evidence for human control of fire only ("only") dates to 400,000 years ago. No fire, no cooking. The few archaeological sites in Africa, Asia, and Europe with trace fire evidence dating back to 700,000 to 1.5 million years ago are open air, meaning wildfires cannot be ruled out, or are inconclusive for other reasons.

Now a new paper published this week provides what the authors call "unambiguous evidence in the form of burned bone and ashed plant remains" that "burning events" occurred in Wonderwerk Cave, an archaeological site in South Africa, one million years ago. The archaeologists -- led by Francsco Berna of Boston University -- have been working in the cave, "an approximately 140-m-long phreatic tube," since 2004. Kate Wong explains at Scientific American:

Berna's team obtained blocks of sediment from a layer in the cave that contains stone tools made in the so-called Acheulean tradition, which is believed to have originated with the early human ancestor Homo erectus. Studying thin sections of the sediment blocks under a microscope, the scientists observed lots of ashed plant remains and tiny fragments of burned bone. Further analysis of the thin sections using Fourier transform infrared microspectroscopy, which reveals molecular structure, showed that some of the bones had been heated to temperatures of around 500 degrees Celsius. Preliminary data suggest that leaves and grasses, rather than wood, fueled these ancient fires. All told, the burned remains appear to have been the products of repeated, local combustion episodes that occurred in the vicinity of where the remains were discovered, 30 meters in from mouth of the cave.

Additionally, the team did not find traces of berlinite and hydroxylellestadite, two minerals that "characteristically form during spontaneous combustion of bat guano -- a rare event but one documented inside caves" (a very wonderful phrase if there ever was).

Evidence for the earliest stone tools still predates the control of fire, by hundreds of thousands of years, but the authors of the paper believe that the techniques they used to study the Wonderwerk sediments may result in discoveries of even earlier "burning events."

Presented by

Rebecca J. Rosen is a senior editor at The Atlantic, where she oversees the Business Channel. She was previously an associate editor at The Wilson Quarterly.

Things Not to Say to a Pregnant Woman

You don't have to tell her how big she is. You don't need to touch her belly.

Join the Discussion

After you comment, click Post. If you’re not already logged in you will be asked to log in or register.

blog comments powered by Disqus

Video

Things Not to Say to a Pregnant Woman

You don't have to tell her how big she is. You don't need to touch her belly.

Video

Maine's Underground Street Art

"Graffiti is the farthest thing from anarchy."

Video

The Joy of Running in a Beautiful Place

A love letter to California's Marin Headlands

Video

'I Didn't Even Know What I Was Going Through'

A 17-year-old describes his struggles with depression.

Video

Google Street View, Transformed Into a Tiny Planet

A 360-degree tour of our world, made entirely from Google's panoramas

Video

The Farmer Who Won't Quit

A filmmaker returns to his hometown to profile the patriarch of a family farm

Video

Riding Unicycles in a Cave

"If you fall down and break your leg, there's no way out."

Video

Carrot: A Pitch-Perfect Satire of Tech

"It's not just a vegetable. It's what a vegetable should be."

More in Technology

Just In