We know that humans and Neanderthals met and integrated in Europe, but we don't know in which specific regions this actually happened. The study, which was published in the journal Scientific Reports1, did not provide evidence that humans directly interacted with Neanderthals around 42,000 years ago, but earlier genetic research has shown that they must have at some point. Though prior fossil evidence has revealed that modern humans and Neanderthals wandered the Earth at the same time for millions of years, the precise timing of this event has also been elusive.

The team examined radiocarbon dating for 56 artifacts from 17 sites in France and northern Spain, 28 of which were Neanderthal artifacts. Bones and unusual stone knives said to have been created by some of the last Neanderthals in the area were among the artifacts found. After then, the researchers utilized Bayesian modeling to select a smaller range of possible dates.