The bone was no bigger than a coffee bean. It was a bit of pinky from a young girl that could have easily been missed among the thousands of bones dug up by archaeologists at the site each year.
Yet the unassuming fossil made it out of Denisova Cave in Siberia’s Altai Mountains and into the Max Planck Institute’s ancient DNA laboratory in Leipzig, Germany, where in 2010 it yielded a complete genome of a previously unknown type of human.
“No one had suspected such a population was out there,” says geneticist Matthias Meyer, who worked on the specimen.
That partial finger bone was the first evidence of the Denisovans, a distinct branch of the Homo family tree, whose members mated with both Neanderthals and modern humans during the past 100,000 years. Denisovans may have roamed vast expanses of Asia with tools as sophisticated as those made by modern humans at the time. But years have passed since the discovery of the Denisovans, and the only tangible evidence of them is still that pinky nub and three additional molars from the same cave.
The little finger belonged to someone who was still growing, but is otherwise nondescript. The molars are big — larger than those of any recent humans and within the range of pre-human Australopithecines who lived millions of years ago.
