60秒科学:Grain Use Well before Modern Agriculture（在线收听）

Grain Use Well before Modern Agriculture
A study in the journal Science finds evidence that early modern humans were making use of grains, which required significant processing before eating, 100,000 years ago. Cynthia Graber reports

Some of our early ancestors weren’t just scavenging fruit and nuts and hunting animals. That’s the conclusion of scientists who discovered evidence of the grain sorghum on hundred-thousand-year-old stone tools. The tools were discovered deep in a cave in northwest Mozambique. The research appears in the December 18th issue of the journal Science.

The general belief had been that these ancient people in southern Africa preferred to concentrate on more accessible foods, such as fruit, nuts and roots. They wouldn’t have bothered with seeds and starchy grains, it was thought, because those foods were too difficult to get and prepare. In this scenario, grains would become a regular part of the diet much later in history.

But a researcher [Julio Mercader], from the University of Calgary, decided to survey 70 stone tools found in one of the deep chambers of a long cave. And about 80 percent of the tools contained residues of grains. Grinding and scraping tools showed the most grain evidence. And the grains appear to have been highly processed: boiled, fermented or ground.

Sorghum is still used widely today in Africa. Now it looks as if it might be part of the original family recipe.