In 1856, some curious remains turned up at a limestone quarry in the Neander Valley in Germany. While the skull fragment and bones vaguely resembled those of modern humans, the brow was too robust, and the bones were too hefty. It took eight years for scientists to recognize the fossils as the first evidence of a whole other species of ancient human, Homo neanderthalensis.

Further discoveries have since revealed much more about the Neanderthals, including where they lived, how they cared for their young, and perhaps even their artwork. Now, using ancient DNA extracted from a pair of European Neanderthals, scientists are getting a more detailed picture of the species’ journey across our prehistoric planet.

The predecessors of