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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

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