A new study claims that he first humans often engaged in sexual activities and interbred several times over more than 35,000 years.
It was previously thought that sexual interactions between Neanderthals and other primitive humans were quite rare but new results point to a completely different direction. DNA analysis revealed that modern humans come for Africa and they started to migrate towards Asia and Europe almost 75,000 years ago.
Collected samples from over 1,000 genomes project hint that early humans were very promiscuous. They used to have a vast network of relationships where members of one group had constant intercourse with other members of the group or even other hominid species.
Researchers now believe that almost any contact between two groups led to mating at some point. The main problem here is that due to lack of evidence it is very hard to identify one group from another.
Data also suggests that interbreeding was a widespread phenomenon back in those days. Contact between different hominid groups may have led to interbreeding between Neanderthals and the modern humans that were beginning to surface.
Another study discovered that Denisovans, a relative of Neanderthals, also had intercourse with them and other hominid species. The Denisovans were discovered in the South of Siberia ten years ago, and feature distinctive genetic differences that separate them from Neanderthals and other humans.
When our modern ancestors left Africa and reached Europe and Asia they stumbled upon Neanderthals. This can be observed in our genetic making since approximately 2% of our DNA comes from Neanderthals.
At first researchers believed that only one interbreeding session took place. Samples from East Asia have a higher amount of Neanderthal DNA, hinting that more encounters may have taken place.
While it was already known that modern humans are the result of mixture between early humans and Neanderthals the higher ratio of Neanderthal DNA in the case of East Asia cannot be explained at this point as further research is needed.