After removing several metres of sediment from an ancient, underground river bed deep inside a limestone cave in Bijie, Guizhou, a team of researchers led by Professor Zhao Lingxia discovered three human teeth.

Anatomically, they resembled those of modern humans, but dating of the sediment showed they were buried 112,000 to 178,000 years ago, before the first modern humans walked out of Africa, around 75,000 years ago.

The team’s discovery three years ago, detailed in a paper in the journal Acta Anthropologica Sinica earlier this year, added a new piece to the puzzle of Chinese origins but not the full picture, in the absence of DNA analysis.