For today’s Buddhist monks, Baishiya Karst Cave, 3200 meters high on the Tibetan Plateau, is holy. For the ancient Denisovans, extinct hominins known only from DNA, teeth, and bits of bone found in another cave 2800 kilometers away in Siberia, it was a favorite rest stop. Last year, researchers proposed that a jawbone found long ago in the Tibetan cave was Denisovan, based on its ancient proteins. But archaeologist Dongju Zhang of Lanzhou University and her team were on a quest for more definitive evidence. So in December, 2018, they began to dig. This week, Zhang’s team reports the first Denisovan ancient DNA found outside Denisova Cave: mitochondrial DNA gleaned not from fossils, but from the cave sediments themselves. Precise dates show the Denisovans took shelter in the cave 100,000 years and 60,000 years ago, and possibly as recently as 45,000 years ago when modern humans were flowing into Asia.
There has been circumstantial evidence that this was the case for a while, but finding Denisovan ancient DNA at a new location with a quite recent timeframe is helpful in expanding our understanding of this archaic species of hominins.