In arid northwest China and Korea, millet, rather than rice, formed an important part of the prehistoric diet. Now, new evidence from dated plant remains from a Neolithic site at Dadiwan, in western China, shows that millet was being consumed as early as 7,900 years ago. Initially it was not clear from the Dadiwan remains whether millet cultivation and consumption was small-scale or large. Now a study of the carbon isotopes in dog and pig bones from the site suggests that both species were fed on a millet-rich diet. Seth Newsome, co-author of the study, carried out at the Carnegie Institution’s Geophysical Laboratory, argues that ‘if the dogs were consuming that much millet, their human masters were probably doing the same’.
Of the plants that grow in this part of China, millet is one of the few that contains the heavy carbon isotope known as C4 — most other plant foods have the lighter C2 isotope. The researchers found that most of the dog bones dating right back to the earliest phases at the site bore the C4 isotopic signature, suggesting that they were domesticated and being fed by humans (millet is not a grain that wild dogs eat in large quantities).
Bones of pigs from the site tell a slightly different story. The Phase 1 pig bones (7,900 to 7,200 years ago) showed no signs of millet in the diet, whereas the Phase 2 bones (6,500 to 4,900 years ago) do, suggesting that the earlier bones are of wild pigs and that pigs had been domesticated by the later phase of occupation.
‘Our results help fill in the picture of how agriculture arose in this part of the world,’ says Newsome. ‘There has been speculation that agriculture spread north from southern rice-farming areas, but the Phase 1 people were experimenting with agriculture by cultivating local grains. This simple system was later replaced in Phase 2 by a much more developed agricultural system.’ •
This article is an extract from the full article published in World Archaeology Issue 35. Click here to subscribe