The spread of domesticated rice in eastern and southeastern Asia was mainly demic

The Neolithic transition, i.e., the shift from hunting and gathering into farming, had a major impact in many aspects of human societies, from economics to demography and from health to ideology. There are two main models of Neolithic spread. The demic model assumes that the Neolithic spread mainly due to the diffusion of farming populations, whereas the cultural model considers that it was essentially due to transmission of cultural traits (domesticates and knowledge) from farmers to hunter-gatherers (without substantial diffusion of farmers themselves). Here we estimate the spread rate of the Neolithic transition in eastern and southeastern Asia, using Early Neolithic dates of 201 archaeological sites with domesticated rice (Oryza sativa). We show that domesticated rice, a staple Neolithic crop in eastern and southeastern Asia, spread at a rate of 0.72–0.92 km/yr (95% confidence level). Comparing these results to the predictions of a demic-cultural model implies that demic diffusion explains more than 76% of the spread observed rate, whereas cultural diffusion played a secondary role.