Prehistoric mummy puzzle

Adult female skeleton

Adult female skeleton

7 September 2012 by Tamera Jones

Mummified bodies made of chopped up people? It's not a legend from ancient Egypt but a find from the Outer Hebrides. Tamera Jones finds out how the latest forensic techniques were applied to the mystery of Britain's first prehistoric mummies.

When Professor Mike Parker Pearson from the University of Sheffield started excavating the Bronze Age Cladh Hallan settlement on South Uist, one of the first things his team found was a row of three roundhouses. Radio-carbon dating showed they were built around 1100 BC.

Further digging revealed several burials directly under the houses. Not so unusual in itself, but the archaeologists were surprised by the contorted and scrunched-up positions of the skeletons, which looked similar to mummy bundles found in Peru.

"We also noticed that the male skeleton had a full set of teeth in his lower jaw, but the upper set was completely missing," says Pearson. "Our first thought was that this was some kind of Bronze Age torture victim."

But forensic pathology showed the two jaws didn't match at all. Several months of painstaking analysis revealed that in fact the man's skull, mandible and torso came from three different people.

"It looked like these individuals had been cut up and put back together to look like one person," says Pearson.

Then the mystery deepened even further. When the bodies were dated they turned out to be several hundred years older than the houses, which meant they had been stored for several generations before they were buried.

Adult male skeleton

Adult male skeleton

The position of the bones in both adult skeletons suggested they had still been held together by soft tissue when they were buried, so they had been stored with particular care.

Pearson and biomedical archaeologist Professor Terry Brown from the University of Manchester, took the remains to NERC's Isotope Geosciences Laboratory where scientists used a range of techniques to work out where the bodies might have been kept. These included the rather grisly mercury intrusion porosimetry, which shows how far gut bacteria has eaten into the surrounding bones after death. In this case, not very far; decay had started in the male's torso but then something had stopped it, and there was no sign of decay in the female corpse at all.

Other techniques showed Pearson and his colleagues that the surfaces of the bones had become demineralised, something that happens in an acidic environment. All the forensic evidence suggested that the bodies had been preserved in a peat bog for several months before being taken out and dried. They must then have been stored above ground for hundreds of years before being merged with other mummified individuals and finally buried.

"At the time this was the first ever evidence of mummification outside of South America and Egypt," says Pearson. "Before this, mummification in the British Bronze Age was unheard of."

Most recently, DNA from the female's skull, jaw, arm and thigh bones has shown that, just like the male, the woman's skeleton was made up of at least three individuals - and the cranium and mandible were male.

What led our ancestors to mummify and combine these bodies is anyone's guess. But Pearson thinks it has something to do with merging ancestries.

"Lots of fields and ditches were being built across Britain in the middle Bronze Age", he says. "An obvious thing to do would be to coalesce ancestors' remains as a way of asserting rights over this newly enclosed land."