Referring to humans that lives 40,000-50,000 years ago as “modern” may be more accurate than you think – just like us they apparently had an insatiable desire to hump whoever was around. A study of one of the oldest-known bones from a modern human in Europe suggests that we were interbreeding with Neanderthals for generations before they went extinct approximately 40,000 years ago.

While scientists have long suspected the two closely-related species exchanged genetic material, it was believed that the two only mixed in the Middle East as early humans left Africa. However, the jawbone of a man who lived in Romania between 37,000 and 42,000 years ago suggests his DNA was 6-9% Neanderthal, indicating he was several generations removed from the original interbreeding.

“The genetic data show that he was a member of a pioneer population of modern humans who got to Europe early, mixed with local Neanderthals and then was displaced by later migrations,” said David Reich, Harvard Medical School professor of genetics, who led the study’s analyses of population history.

The man, whose remains were found in 2002 in Oase Cave, may not have contributed much to humans living in Europe today, but the impact of the interbreeding occurring at the time remains – every present-day human with origins outside of sub-Saharan Africa carries 1-3% Neanderthal DNA in their genomes.

“We have previously shown that Oase is indeed the oldest modern human in Europe known so far, and now this research confirms that the individual had a Neanderthal ancestor. What more could we wish for?” added Romanian researcher Silviu Constantin.

Neanderthal DNA differs from our own by just 0.12%, close enough that some experts consider them a subspecies of modern humans. The latest finds suggest they were just as sophisticated as humans of the time, with the capacity to speak, hunt, grieve for their dead and even build rudimentary sailing vessels. No one’s sure why they went extinct; well-regarded theories suggest they died out due to climate change, newly-introduced diseases from modern humans, interbreeding with modern humans, or some combination of the three.