Study finds prevalence of incest among Neanderthals

Researchers studying the DNA from the fossilised toe of a 50,000 year-old Siberian Neanderthal woman have concluded that she was the child of two closely related parents.

The findings, published in the scientific journal Nature, point to the prevalence of incest among Neanderthals, the nearest extinct relatives of modern humans.

The toe bone was recovered by Russian archaeologists from a Siberian cave in 2010, and allowed scientists to extract, sequence and analyse the woman's genome.

The researchers ran the information through a series of simulated inbreeding scenarios, which revealed that her parents were either half-siblings who shared the same mother or double first cousins.

The genetic clues pointed to the possibility of her parents coming from different generations of the same extended family.

According to one of the researchers, University of California at Berkley population geneticist Montgomery Slatkin, this could include an aunt and nephew, an uncle and niece, a grandfather and granddaughter or a grandmother and grandson.

According to deputy director of the University of Adelaide's Australian centre for ancient DNA Jeremy Austin, given the odds of randomly finding the only Neanderthal bone with evidence of incest was slim, this toe bone likely told a common story of inbreeding.

He added the woman lived close to the period of shrinking population, when the Neanderthals went extinct, which would have offered limited partnering opportunities.

Neanderthals once dwelt across a vast area ranging from Europe to the Middle East to western Asia.

Meanwhile, a Neanderthal skeleton first unearthed in a cave in southwestern France over a century ago was intentionally buried, according to a new 13-year reanalysis of the site.

The finding confirms that careful burials existed among early humans at least 50,000 years ago, and that the companions of the Neanderthal took great care to dig their dead a grave and protect their bodies from scavengers, according to the study authors in the Proceedings of the National Academy of Sciences.

Led by New York University paleontologist William Rendu, the study marks a closure to a long-standing debate about the Neanderthal site and its remains.

National Geographic quoted Francesco d'Errico, an archeologist at the University of Bordeaux in France who was not involved in the study, as saying there had been a tendency among researchers working on this topic to discard all evidence coming from old excavations just because the excavations were done long ago.

Most anthropologists are now in agreement following evidence collected from 20 or so grave sites throughout Western Europe, that the closest evolutionary relatives of humans buried their dead at least some of the time.