Limitations of carbon dating

Beside a slab of trilobites, in a quiet corner of Britain's Oxford University Museum of Natural History, lies a collection of ochre-tinted human bones known as the Red Lady of Paviland.

In 1823, palaeontologist William Buckland painstakingly removed the fossils from a cave in Wales, and discovered ivory rods, shell beads and other ornaments in the vicinity.

He concluded that they belonged to a Roman-era witch or prostitute.

Buckland's immediate successors did a little better.

They determined that the Red Lady was in fact a man, and that the ornaments resembled those found at much older sites in continental Europe.

Then, in the twentieth century, carbon dating found the bones to be about 22,000 years old — even though much of Britain was encased in ice and seemingly uninhabitable for part of that time.

When Higham eventually got the bones, his team came up with a more likely scenario: they were closer to 33,000 years old and one of the earliest examples of ceremonial burial in Western Europe.

“It is another sobering example of cocked-up dates,” says Higham, whose laboratory is leading a revolution in radiocarbon dating.

By developing techniques that strip ancient samples of impurities, he and his team have established more accurate ages for the remains from dozens of archaeological sites.

In the process, Higham is rewriting European history for around 30,000–50,000 years ago — a time referred to as the Middle-to-Upper Palaeolithic transition — when the first modern-looking humans arrived from Africa and the last Neanderthals vanished.

Higham thinks that better carbon dating will help to resolve debates about whether the two ever met, swapped ideas or even had sex.

It might even explain why humans survived and Neanderthals did not.

“I admire him,” says Paul Mellars, an archaeologist from the University of Cambridge, UK, and an expert on this period in Europe, for “the sheer doggedness and sense of vision” he has for improving radiocarbon dating of the Palaeolithic.

That vision sometimes clashes with other scientists' views, but Higham makes no apologies for his interpretations as long as the dates are solid.

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