Earlier this month in Nature, scientists revealed that they’d sequenced mitochondrial DNA from a 400,000 year old fossil dug out of a pit in northern Spain. That gives this team the official record for sequencing the most ancient human DNA yet, but record-smashing was the least interesting aspect of the news.
The previous record was for sequencing 100,000 year old Neanderthal DNA. The result suggested our ancestors may have interbred at least a little with this otherwise extinct lineage. The new sequencing feat promised yet more revelations about a fascinating period, when members of our genus, homo, had ventured out of Africa and started populating Europe and Asia.
What the researchers found was a surprise. They expected Spanish fossil’s DNA to show a close relationship to Neanderthals, but instead it resembled DNA from another group, the Densiovans, whose remains have turned up in Siberia.
The story cried out for some...