I came across this story on the BBC, and I find it fascinating. It has long been suspected that some humans interbred with Neandertals, but a recent discovery found a previously undisclosed type of ancient human in Asia -- and their DNA lives on in at least some modern people.
Here are some details.
Ancient humans, dubbed 'Denisovans', interbred with us
By Pallab Ghosh
Science correspondent, BBC News
Scientists say an entirely separate type of human identified from bones in Siberia co-existed and interbred with our own species.
The ancient humans have been dubbed "Denisovans" after the caves in Siberia where their remains were found.
There is also evidence that this population was widespread in Eurasia.
A study in Nature journal shows that Denisovans co-existed with Neanderthals and interbred with our species - perhaps around 50,000 years ago.