Eating Plants in the Chinese Paleolithic

Around the world, evidence for the processing of plant food in the Paleolithic, especially the grinding of seeds, continues to mount:

Li Liu of Stanford University and colleagues studied three grinding stones from China's Yellow River region. They bear residues showing that they were used to process millet and other grains, as well as yams, beans and roots. The stones date from 23,000 to 19,500 years ago, late in the last ice age. But the earliest archaeological evidence for crop cultivation in China is 11,000 years old, suggesting that farming was slow to emerge from ancient traditions of plant use.

So much for the grain-free "paleo diet." The techniques being used to identify plant residues are new and experimental, but in a way the grinding stones speak for themselves. The facts of our own physiology -- whatever the "best" diet turns out to be, we can certainly be very healthy eating a grain-rich Mediterranean or Japanese diet -- also argue that we have been eating grains and beans for a long time.