New research suggests that our ancestors may have been more skillful in the kitchen than we thought. A team of Italian scientists has found what may be the oldest direct evidence of humans grinding plants into flour, suggesting that grains were on the menu 20,000 years before farming became the norm.
The idea of "man the hunter" dominates popular preconceptions of early humans. But that's grossly oversimplified, says lead author Anna Revedin of the Italian Institute of Prehistory and Early History in Florence. Although meat was a crucial part of the early human diet, she says, plants were necessary fare as well. Plant remains don't last as long as bones, however, and even though some studies have found evidence of potential grinding tools in prehistoric sites, the stones may have been used just to crush red ochre for cave or face painting.
That's why the new find is so important, says Revedin. Her team has discovered ancient starch grains on grinding tools buried at three prehistoric settlements in the valleys and floodplains of Italy, Russia, and the Czech Republic. The researchers calculated the ages of the artifacts by carbon dating charcoal found in the same layers. The oldest samples were from the Russian site and roughly 32,000 years old, Revedin and colleagues report online today in the Proceedings of the National Academy of Sciences. This makes them the oldest in Europe and possibly the oldest in the world; a 1997 study found evidence of seed grinding in Australia at just under 31,000 years ago. What's more, the discoveries suggest that humans were cooking with grains long before agriculture took over roughly 10,000 years ago.
The grains came mostly from roots, stems, and leaves of cattail and fern plants, not the typical wheat and barley of modern farmers. After grinding, the early chefs most likely added water and cooked up a flatbread or soup, says co-author Laura Longo of the University of Siena in Italy. Because gathering and cooking were largely women's work, Revedin says evidence of grinding indicates an increasingly vital role for women in prehistoric societies.
It's an important finding, and in general the study is solid, says Lisa Kealhofer, an anthropologist at Santa Clara University in California. But she cautions that the word "flour" is a bit of misnomer, because the starch grains weren't what 21st century people normally associate with bread making. She also says that without knowing the amount of starch in the surrounding soil, it's difficult to be sure that the grains came from human activity and didn't merely stick to the stones after burial. Longo says she's fairly certain that didn't happen; the grains have been deformed, she notes, and they tend to cluster around the parts of the tools used for grinding.
For Ofer Bar-Yosef, an archaeologist at Harvard University who specializes in the Stone Age, the idea that modern humans ground plants more than 30,000 years ago isn't a shock. He says he wouldn't be astonished if our closest cousins also did more than eat their greens raw. "I bet you that even Neandertals had much more complex food-preparation techniques when it comes to plants." (However, new evidence suggests that Neandertals may not have been as sophisticated as we thought.)
Steven Kuhn, an anthropologist at the University of Arizona in Tucson, says he's more impressed with the location of the artifacts than the age. That humans were gathering and grinding plants as far north as Europe, when plants were more common in the warmer south, is a bit surprising. He also says that although the age of the tools is intriguing, "it's a rule in this business that anything you claim is the oldest, somebody is always going to find something older eventually."
* This article has been corrected. Revedin's team discovered ancient starch grains on grinding tools
buried at three prehistoric settlements in the valleys and floodplains
of Italy, Russia, and the Czech Republic, but not in Turkey as originally reported.