After analyzing 47 teeth discovered in a karst cave in southern China, researchers have revealed that anatomically modern humans reached the area between 80,000 and 120,000 years ago. That means the first humans out of Africa ventured into China – and not Europe. The findings were published in Nature this week.
Our species originated in Africa nearly 200,000 years ago, but when and through what routes Homo sapiens dispersed onto other continents is still debated. Some believe an initial failed dispersal meant we didn’t move out and eastward until around 60,000 years ago. There hasn’t been much to go on in the fossil record between the eastern Mediterranean and southeast Asia for the Late Pleistocene, between 12,000 and 126,000 years ago. In fact, well-preserved Homo sapiens fossils older than 45,000 years have been rare, until now.
Between 2011 and 2013, excavations in a 3,000-square-meter (30,000-square-foot) area within Fuyan Cave (pictured below) in Daoxian County of Hunan Province have yielded a trove of 47 human teeth, along with other mammal fossils. These included mostly more teeth from the ancestors of giant pandas, hyenas, tapirs, and ancient mammoth relatives. No stone tools have been found yet, suggesting that the humans didn’t actually live there.
By dating the stalagmites that formed after the fossils were buried, an international team led by Wu Liu and Xiu-jie Wu from the Chinese Academy of Sciences and University College London’s María Martinón-Torres found the teeth to be at least 80,000 years old. The associated Late Pleistocene mammals suggest that the teeth are no more than 120,000 years old.
There was no genetic material, but a detailed morphological analysis – including overall shape, crown dimensions, and cusp measurements – indicates that the Daoxian teeth belonged to members of our species. That makes these the earliest, unequivocal evidence of modern humans in southern China. The teeth resembled those of people today as well as Late Pleistocene Europeans. They were smaller than Late Pleistocene dental samples from Asia and Africa, and less primitive than those of populations in central and northern China during that same time period. Homo sapiens may have left Africa several times.
The findings indicate that humans with fully modern features were living in southern China 35,000 to 75,000 years earlier than in the eastern Mediterranean or Europe. This is not surprising, University of Exeter’s Robin Dennell writes in an accompanying article. Since Homo sapiens originated near the tropics, it makes sense that the initial dispersal was eastwards rather than northwards to below freezing winter temperatures.
Additionally, since there’s no evidence that our species entered Europe before 45,000 years ago, the team thinks that Neanderthals may have been a barrier for modern humans. It’s possible that the species couldn’t settle in Europe until the demise of Neanderthals had already begun.
Geographical location and interior views of the Fuyan Cave, Doaxian with dating sample (lower left), plan view of the excavation area with stratigraphy layer marked (center), the spatial relationship of the excavated regions and researcher finding human tooth (right). Y-J Cai, X-X Yang, and X-J Wu