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It seems that the idea of free love started a lot earlier than the 1960s. An international team of researchers has found a tiny bone fragment belonging to an ancient hominin, named ‘Denny’ by the team, that had a Neanderthal for a mother and a Denisovan for a father – two of the closest extinct relatives of currently living humans.
Up until around 40,000 years ago, the two groups are known to have lived on the combined continent of Eurasia – Neanderthals in the west of the continent, Denisovans in the east. Previous genetic studies of ancient hominin remains have shown that they sometimes interbred, but Denny is the only known example of a first-generation child with equal parts Neanderthal and Denisovan DNA.
The bone fragment was found in 2012 at Denisova Cave in Russia and taken to the Max Planck Institute in Leipzig for genetic analysis, after being identified as a hominin bone due to its protein composition. It is thought that the bone is a fragment of the arm or leg of a young female, who would have been aged around 13 when she died some 90,000 years ago.
“It is striking that we find this Neanderthal/ Denisovan child among the handful of ancient individuals whose genomes have been sequenced,” said Prof Svante Pääbo at the Max Planck Institute. “Neanderthals and Denisovans may not have had many opportunities to meet. But when they did, they must have mated frequently – much more so than we previously thought.”
Genetic analysis of the bone indicates that the mother was more closely related to the 55,000-year-old Neanderthal remains found in the Vindija Cave in western Europe than those of another, the so-called Altai Neanderthal, that lived in the Denisova Cave at an earlier date. This means that Neanderthals must have at some point travelled between western and eastern Europe.
The team also found evidence in the genome that the Denisovan father had at least one Neanderthal ancestor further back in his family tree – between 8,000 and 17,000 years before Denny lived
“An interesting aspect of this genome is that it allows us to learn things about two populations – the Neanderthals from the mother’s side, and the Denisovans from the father’s side,” said Dr Fabrizio Mafessoni, also from the Max Planck Institute.
“DENNY IS THE ONLY KNOWN EXAMPLE OF A FIRSTGENERATION CHILD WITH EQUAL PARTS NEANDERTHAL AND DENISOVAN DNA”
ABOVE: The bone fragments unearthed in Siberia in 2012 1 cm
BELOW: Work at the cave is still ongoing