When our ancestors first migrated out of Africa around 60,000 years ago, they were not alone. At that time, at least two other species of hominid cousins walked the Eurasian landmass—Neanderthals and Denisovans. As our modern human ancestors migrated through Eurasia, they encountered the Neanderthals and interbred. Because of this, a small amount of Neanderthal DNA was introduced into the modern human gene pool.
Genetics tell us something of our origins. People who have Neanderthal DNA in their genetic makeup can be identified. And, since the discovery of a small bone inside the Denisova cave, a third group can be identified.
Inside the cave, and how the archeologists work.