A review on the spread of prehistoric agriculture from southern China to mainland Southeast Asia

The origins and spread of agriculture was one of the milestones in human history. When and how prehistoric agriculture spread to mainland Southeast Asia is highly concerned, which contributed to the formation of modern Austroasiatic in this region. Previous studies mainly focused on the time and route of rice agriculture's introduction into Southeast Asia while millet agriculture was not paid proper attention. Here we analyze 312 C-14 dating data yielded from charred seeds of rice (Oryza sativa), foxtail millet (Setaria italica) and broomcorn millet (Panicum miliaceum) from 128 archaeological sites in China and mainland Southeast Asia. The result shows that millet farming was introduced to mainland Southeast Asia in the late third millennium BC and rice farming was in the late second millennium BC. The agriculture of mainland Southeast Asia might originate from three areas, Southwest China, Guangxi-West Guangdong and coastal Fujian. The spread route of ancient agriculture in Southwest China is close to the "Southwest Silk Road" recorded in literature, which implies there was possibly a channel of cultural exchanges on the eastern margin of Tibetan Plateau already in the late Neolithic period, laying the foundation for the Southwest Silk Road later.