According to a new study, analysis of genetic material from a 40,000-year-old Romanian human jawbone gave evidence of sex between Europeans and Neanderthals.

The DNA tests suggested that the man had two to four times more Neanderthal DNA than any other modern human tested.

He inherited the DNA when an ancestor had sex with a Neanderthal about 200 years earlier, or four to six generations back in his family tree. This indicated that the earliest Homo sapiens to settle in Europe from Africa interbred with local Neanderthals.

Although Neanderthals went extinct approximately 40,000 years ago, their DNA lived on. Europeans and Asians inherited between 1% and 4% of Neanderthals' genetic material.

It was previously thought that early humans migrated out of Africa mixed with Neanderthals in the Middle East some 55,000 years ago, before spreading to the rest of the world. They did not mix again with Neanderthals.

Scientists have named this human "Oase 1," after the cave in which he was found. The extracted jawbone from the Romanian has been claimed to come from the oldest modern human found in Europe.

Lead author, David Reich of the Howard Hughes Medical Institute at Harvard Medical School said, “The sample is more closely related to Neanderthals than any other modern human we’ve ever looked at before".

He said the man was part of an early migration of modern humans to Europe and might have interacted closely with Neanderthals.