DNA analysis of 400,000 year old bones found in Spain, the oldest known human remains, has yielded more questions than answers. The human family tree is now thought to have had many more branches than previously thought after the analysis which was the first time scientists could gain data from this period.
Originally it was thought the bones may have been Neanderthal but instead the bones have a closer relationship to Denisovans, a distinct human sub-species who lived in Siberia. The Denisovans interbred with the Neanderthals and Modern Humans, bones from the other human species found alongside their's, and traces of their DNA remains in humans today. Around 6% of the DNA in Melanesian people (living in places like Papua New Guinea) is shared with the Denisovans. Indeed around 4% of the DNA in non-Africans is Neanderthal.