The mitochondrial DNA of a femur 400,000 years old cofuses the picture of who is our grandma:-"The team sequenced most of the femur's mitochondrial genome, which is made up of DNA from the cell's energy-producing structures and passed down the maternal line. The resulting phylogenetic analysis ­— which shows branches in evolutionary history — placed the DNA closer to that of Denisovans than to Neanderthals or modern humans. "This really raises more questions than it answers," Pääbo says."-http://www.nature.com/news/hominin-dna-baffles-experts-1.14294?WT.ec_id=NATURE-20131205