The theory that Neanderthals and modern humans interbred is being called into question through research by Cambridge University researchers.

Dr Andrea Manica, from the University of Cambridge, who led the study said: “Our work shows clearly that the patterns currently seen in the Neanderthal genome are not exceptional, and are in line with our expectations of what we would see without hybridisation. So, if any hybridisation happened – it’s difficult to conclusively prove it never happened – then it would have been minimal and much less than what people are claiming now.”

The theory goes that Neanderthals (which populated Europe) and modern humans (which populated Africa) were not freely mixing. The DNA of Africa’s modern humans simply retained the ancestral DNA they shared with Neanderthals. It’s more likely, according to researchers, that Neanderthals of Europe—which might have had a lot of regional diversity—were interbreeding, while African humans were doing the same.

In short, when humans migrated out of Africa, they did not likely interbreed with European Neanderthals to any great extent, but merely carried with them the latent ancestral DNA the two species shared.

Dr Manica added:

Thus, based on common ancestry and geographic differences among populations within each continent, we would predict out of Africa populations to be more similar to Neanderthals than their African counterparts – exactly the patterns that were observed when the Neanderthal genome was sequenced; but this pattern was attributed to hybridisation. Hopefully, everyone will become more cautious before invoking hybridisation, and start taking into account that ancient populations differed from each other probably as much as modern populations do.

So there you have it: humans and Neanderthals probably didn’t make sweet love. And if they did, it was probably just the tip.