Teeth from China Reveal an Early Human Trek out of Africa

Teeth from a cave in south China show that Homo sapiens reached China around 100,000 years ago—a time at which most researchers had assumed that our species had not trekked far beyond Africa.

“This is stunning, it’s major league,” says Michael Petraglia, an archaeologist at the University of Oxford, UK who was not involved in the research. “It’s one of the most important finds coming out of Asia in the last decade.”

Limestone caves pockmark Daoxian County in Hunan Province, China. Recent excavations of a cave system there extending over 3 square kilometres discovered 47 human teeth, as well as the remains of hyenas, extinct giant pandas and dozens of other animal species. {snip}

The teeth are unquestionably those of H. sapiens, says María Martinón-Torres, a palaeoanthropologist at University College London who co-led the study with colleagues Wu Liu and Xie-jie Wu at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. {snip}

Determining the age of the teeth proved tricky. They contained no radioactive carbon (which has almost vanished after 50,000 years). So the team dated various calcite deposits in the cave and used the assortment of animal remains to deduce that the human teeth were probably between 80,000 and 120,000 years old.

Early trekkers

Those ages buck the conventional wisdom that H. sapiens from Africa began colonizing the world only around 50,000–60,000 years ago, says Martinón-Torres. Older traces of modern humans have been seen outside Africa, such as the roughly 100,000-year-old remains from the Skhul and Qafzeh Caves in Israel. But many researchers had argued that those remains were only evidence of unsuccessful efforts at wider migration.

“This demonstrates it was not a failed dispersal,” says Petraglia, who has long argued for an early expansion of modern humans through Asia on a southerly route. {snip}

Without DNA from the teeth, it is impossible to determine the relationship between the Daoxian people and other humans, including present-day Asians. {snip}

It is also not clear why modern humans would have reached East Asia so long before they reached Europe, where the earliest remains are about 45,000 years old. Martinón-Torres suggests that humans could not gain a foothold in Europe until Neanderthals there were teetering on extinction. The frigid climate of Ice Age Europe may have erected another barrier to people adapted to Africa, says Petraglia.

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