Archaeologists identified bone fragments of prehistoric modern humans in Germany, suggesting several millennia of coexistence with Neanderthals before the species disappeared

Modern humans had already settled in northwest Europe thousands of years before Neanderthals vanished forever in the southwest of the continent, according to the results of a recent excavation in Ranis, Germany. The new findings offer unprecedented insight into the two species’ interaction, suggesting they lived side by side and might have even interbred.

At the base of a medieval castle, 24 feet deep into the layered sediment of the Ilsenhöhle cave, scientists unearthed leaf-shaped spear points, animal remains and 13 bone fragments identified as early modern humans—evidence that Homo sapiens existed in northern Europe 45,000 years ago.

“Because of the age of this site and location, we know Neanderthals and humans quite definitively had a large overlap,” says study co-author Elena Zavala, a paleo and forensic geneticist at the University of California, Berkeley, to NBC News’ Evan Bush.