A site in northern China sheds light on ancient human migration into East Asia 45,000 years ago and highlights a unique convergence of culture and technology.

The site’s discovery challenges conventional beliefs about how Homo sapiens dispersed around the world.

An international team of researchers examined a trove of ancient human artefacts from the Shiyu site near the city of Shuozhou, about 350km west of Beijing. The research is published in Nature Ecology and Evolution.

The team used radiocarbon and luminescence dating methods to determine that stone and bone tools from the site are 45,000 years old.

The site is the eastern-most and oldest of its kind.

Obsidian was transported from sources hundreds of kilometres away to craft the tools. This indicates advanced resource collection strategies among the ancient people.

Among the tools are a mix of different technologies, such as Levallois and Volumetric Blade Reduction. Levallois reduction is an innovation associated with the Middle Palaeolithic which spanned from 300,000 to 50,000 years ago. But other blade reduction techniques and symbolic tools found at the site are characteristic of the Upper Palaeolithic – roughly 50,000 to 12,000 years ago.

Other Shiyu objects reflect core-flake crafting found elsewhere in China dating to about 40,000 years ago.

Unique artefacts such as a shaped graphite disc and bone tools were also uncovered.

This blending of different technologies illustrates a cultural mixing and adaptation. “The amalgamation of diverse cultural traits signifies a complex and innovative adaptation by our ancestors during their expansion,” says senior author Dr Shi-Xia Yang of the Chinese Academy of Sciences.

Homo sapiens are known to have migrated to eastern Asia at least 45,000 years ago. One 2015 study suggests Homo sapiens teeth found in the Fuyan Cave in southern China date back 80,000–120,000 years.

But when and how ancient humans migrated to East Asia remains a mystery. The Shiyu site suggests it was a complex process.

"he site reflects a process of cultural creolisation – the contact between societies and relocated peoples – blending inherited traits with novel innovations, thus complicating the traditional understanding of Homo sapiens’ global expansion," says co-author Professor Francesco D’Errico of the University of Bordeaux, France.