New evidence from the Qugong site in the central Tibetan Plateau for the prehistoric Highland Silk Road

Located in the central Eurasia, the Tibetan Plateau (TP) is a key area for the spread of culture, technology, and species. However, the Plateau's role in the prehistoric food globalization has been underestimated due to the lack of archeological materials. The Qugong site was the only scientifically excavated site in the central TP up to now. It is the earliest and among the most important prehistoric settlements in the central TP, with charcoals dated to 3750-3500 cal. BP. Wild deer (Cervidae) and domesticated yak (Bos grunniens) and sheep (Ovis aries) remains were unearthed, but no archeobotanical studies had been conducted. Here we present new radiocarbon dating from charred seeds and archeobotanical data of the Qugong site. Dating back to 3400 cal. BP, there were foxtail millet (Setaria italica), broomcorn millet (Panicum miliaceum), wheat (Triticum aestivum), hulled barley (Hordeum vulgare), naked barley (Hordeum vulgarevar.nudum), and bitter buckwheat (Fagopyrum tataricum) identified at this site. We propose millets in the central TP came from the eastern TP, while wheat and barley here probably came from northern South Asia. It indicates that the Eastern and Western cultures arrived in the central TP in prehistory via different routes in late fourth Millennium BP. The intercultural communications not only flourished the prehistoric central TP but also laid the foundation for the later 'Highland Silk Road'.

Automated summary

This study highlights the significance of the Tibetan Plateau in prehistoric food globalization through the examination of the Qugong site, revealing the diverse plant remains and potential sources of grains in the central Tibetan Plateau. It suggests that millets in the region may have originated from the eastern Tibetan Plateau, while wheat and barley likely came from northern South Asia, indicating the complex intercultural exchanges that occurred in prehistory in the region.