Optically stimulated luminescence dating of Paleolithic sites reveals population shifts in North China during the last glacial period

The Greater Khingan and Yanshan mountain ranges in northern China not only constitute a significant physical obstacle to the northward movement of monsoon circulation, but also represent a natural barrier for human migration and cultural interactions between in-migrating Paleolithic populations and those indigenous to East Asia during the Late Pleistocene. We dated two Paleolithic sites, Yangzhuangxishan and Taiziling, located in the southern piedmont of the Yanshan Mountains with artifacts typified by simple core and flake technology associated with foraging populations, to ∼39–29 ka and ∼ 52–47 ka respectively, using the optically stimulated luminescence dating method. Our results indicate that northern China as far south as the Yanshan Mountains was occupied mainly by autochthonous East Asian Paleolithic populations using a core and flake lithic technology, although during this period Initial Upper Paleolithic (IUP) modern humans and Mousterian populations dispersed into East Asia. By synthesizing and integrating the ages of Northeast Asian Paleolithic sequences during the last glacial period (ca. 70–10 ka), we analyzed spatio-temporal variations in Late Pleistocene human populations during relatively cold stadial events (MIS 4 & 2) and warmer interstadials (e.g., MIS 3), revealing an “ebb and flow” pattern for migrations of Western IUP/Mousterian populations and indigenous core and flake technology populations in East Asia corresponding to the advance and retreat of the East Asian monsoon regime. The subsequent extremely cold climate phase engendered a major population shift during the Last Glacial Maximum (ca. 26.5–19 ka) which drove the reduction of both these Paleolithic populations, but afterward facilitated the emergence and rapid dispersal of microlithic technologies in East Asia. The peoples associated with microlithic technologies achieved their maximum geographical extent after the Bølling-Allerød Late Glacial interstadial event (ca. 14.7–12.9 ka) and then gradually decreased, perhaps due to the development of agriculture after ∼13 ka with concomitant increasing settlement stability.