Our ancestors sure were a promiscuous lot. But they didn’t just limit themselves to sleeping with our own species, as ancient humans are known to have mated with other species of human. New evidence now shows that when our ancestors got to Asia, they simply couldn't resist the ancient Denisovans who were already living there, and mated with them in at least two separate events.
We have only been able to discover the existence of the Denisovans due to the advancement in genetic sequencing seen over the last decade or so. This makes the hominins one of the most intriguing species of humans discovered in recent times, and possibly ever.
It all started when archaeologists uncovered a scattering of ancient human remains in a remote cave in the Altai Mountains, dating to roughly 40,000 years ago. The unassuming fossil of a tiny finger bone and a few teeth were nothing special, but then a team of researchers decided to see if they could extract any DNA from them. The results rocked the world of anthropology.
They showed that the bones once belonged to an entirely new species of hominin, distinct from Neanderthals and modern humans who were also known to be living in the region at the same time. Considering they didn’t have a full skeleton to go on (in fact, we still don’t) this was an extraordinary conclusion. It was made more incredible when the genome of the Denisovans was compared to modern humans living today.