Ancient Siberian cave hosted Neanderthals, Denisovans, and modern humans—possibly at the same time

In the past decade, a mere eight human fossils unearthed in the Denisova Cave in southern Siberia have rewritten the human story, from the tiny finger bone that revealed the extinct human Denisovans, to the discovery of a first-generation Neanderthal–Denisovan hybrid. Now a study of DNA in the cave’s soil reveals the complex history of human and animal habitation there. Hundreds of soil samples show a cycle of inhabitants, starting with Denisovans about 300,000 years ago. Different groups of Denisovans and Neanderthals left their marks on the cave, and modern humans appeared about 45,000 years ago.