Neanderthals died out thousands of years earlier than we believed

Neanderthal fossils believed to belong to the last survivors of their species are thousands of years older than scientists once believed.

The Neanderthal fossils in Spy Cave in Belgium were previously dated using radiocarbon, but new tests show that they are actually 44,200 to 40,600 years old.

That is far older than earlier dating, which suggested the bones might be 24,000 years old but was contaminated by what the researchers believe was a glue made from cattle bones, used to preserve the sample.

The new dating by Oxford's Radiocarbon Accelerator suggests that early humans and Neanderthals "overlapped" in Europe - meaning they possibly mated, or interacted with each other.

The research was published in PNAS.

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Professor Tom Higham, of the University of Oxford, said: "Dating is crucial in archaeology, without a reliable framework of chronology we can't really be confident in understanding the relationships between Neanderthals and Homo sapiens as we moved into Europe 45,000 years ago and they began to disappear.

“That's why these methods are so exciting, because they provide much more accurate and reliable dates.

“The results suggest again that Homo sapiens and Neanderthals probably overlapped in different parts of Europe and there must have been opportunities for possible cultural and genetic exchange."

The researchers found that a Neanderthal scapula from the Spy Cave that had been dated as being 28,000 years old was heavily contaminated with modern bovine (cow) DNA.

The researchers believe that the bone may have been preserved with a glue made from cattle bones.

These results suggest that the bone had been preserved with a glue prepared from cattle bones.

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The researchers used "liquid chromatography separation" to extract a single amino acid from the Neanderthal remains and date it.

This helps to exclude contaminants, the researchers said.

Lead author Dr Thibaut Deviese said: "The new chemistry methods we have applied in the case of the Spy and other Belgian sites provide the only means by which we can decontaminate these key Neanderthal bones for dating and check that contaminants have been fully removed.

“This gives us confidence in the new ages we obtained for these important specimens."

Gregory Abrams, of the Scladina Cave Archaeological Centre in Belgium, said: "We also (re)dated neanderthal specimens from two additional Belgian sites, Fonds-de-Foret and Engis, and obtained similar ages than those from Spy. Dating all these Belgian specimens was very exciting as they played a major role in the understanding and the definition of Neanderthals.

“Almost two centuries after the discovery of the Neanderthal child of Engis, we were able to provide a reliable age."

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