The world's oldest louse has been found, in Carlisle. And history, or at least a bit of it, may have to be rewritten.
Archaeologists who found the 2,000-year-old fossilised bug, just one millimetre long, believe it is the first evidence that Romans in Britain, despite their relatively sophisticated lifestyles, had a problem with pubic lice, or crab louse, or Pthirus pubis L.
"It is a big piece of information," said Dr Harry Kenward, a palaeo-entymologist and senior research fellow at York University who was in the team of scientists who helped to discover the Roman bug.
"When we are talking about what it is like to be Roman and trying to make history come alive, we now know it had an itchy-scratchy dimension. We now know they were probably a pretty lousy lot.''
The evolution of Pthirus has long mystified researchers. While the history of the human flea and bed bug are well-documented, ancestors of the crab louse, a slow-moving bug that infects hair on the body rather than the head, has until now kept at least one hop ahead of detection.
Indeed, until the Carlisle louse was unearthed, the oldest ones known to man were found in Iceland and dated from a mere 300 years ago. The previous oldest British louse was aged only 200 years or so and was last alive and thriving in 18th-century London.
Scientists have been looking for early evidence of the louse for many years. Bodies from bogs and mummies of several kinds have been examined, but without success, and the only other animal to suffer with pubic lice is the gorilla.
Dr Kenward, who reports the discovery in the archaeological journal, Antiquity, says the fossil found in a Roman tip also sheds new light on how and when man acquired parasites. It is already known, for instance, that the human flea, which can be traced to Neolithic times, almost certainly came from an animal or a bird before latching on to humans.
The big task Dr Kenward faces now is discovering whether the Romans brought the louse with them, or whether it was already here.
He is now looking for a pre-Roman, Iron Age site, preferably waterlogged, where he and his team can look for the final missing link.