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Plague is a serious disease caused by the bacterium Yersinia Pestis. It is rare nowadays but was responsible for the Great Plague of London in 1665, for example. Looking further back, most people have assumed it presented as the Black Death in the Middle Ages, but with some scholars unconvinced until relatively recently. More daringly, some have wondered if the pandemic that took place in the reign of the Roman emperor Justinian might be the same disease.

Recent work with datable human remains makes it almost curtain that Y. Pestis is indeed what caused all three of these plagues with a small ‘p’. Blood flows into a living tooth, and a pathogen in the blood may be in the teeth of a person when they die. Tooth enamel is very resistant and fragments of pathogen DNA can survive in the tooth for thousands of years.

Researchers have collected DNA samples by drilling into ancient teeth and used computers to reassemble the fragments and look for a sequence that identifies Y. Pestis. Results show that almost certainly the Great Plague of London, the Black Death, and the Justinian plague were the same thing.

And here’s a big surprise; it turns out the bacterium has been about for some 5000 years at least. But it only changed into the deadly form about 4000 years ago, when it swapped in a gene from some other bacterium.

See Ancient Plagues Shaped the World, Scientific American, November 2020.


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Richard Walker


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Edited by Richard Walker, Friday, 18 Mar 2016, 11:54


A hand-axe but a headache too. 

What was it used for?

  • Cooking
  • Leatherworking
  • Carpentry
  • Some other craft
  • Gardening
  • Forestry
  • Hunting
  • Fighting

or some combination of these? Or some other purpose?

Was it fitted to a wooden handle ('hafted')?

If so was it?

  • Bound into a split in the handle
  • Fitted into a socket

Or perhaps it was just hand-held.

Where was it from?

Here we are on firmer ground. It was

  • Found in North Hertfordshire or South Bedfordshire 30+ years ago
  • Made about 4000 years ago in a stone axe factory in North Wales, at Penmaenmawr. BBC 'A History of the World' shows a very similar object. But the BBC site says that axe is made of a rock 'similar to slate'; I'm not sure that's right. I think it may be diorite; any geologists are watching please write in! My hand-axe also seems smaller, about 12 cm.

So it had travelled 200+ hundred miles.

How did the owner lose it (or didn't they?)

The cutting edge is sharp and the polished faces on either side unscratched. So perhaps

  • A stone-axe trader dropped it
  • The owner dropped it on the way home from the local axe-sharpener
  • The owner deliberately discarded it as a offering to supernatural beings. (But it was such a votive offering we would expect to find other objects nearby, and it was found in isolation.)
  • A hunter threw it at a prey animal, missed, then couldn't find the axe again.

We can never know exactly.

The history of objects

When anyone brings an object like this into my local The Moon Under Water, many people ask to see it. Their first question is always 'How old is it?' 

'About 4000 years.' 

'Can I touch it?


And then, reverentially, 

'So apart from you I'm the first person to touch it for 4000 years.' 


Everyone is very quiet and thoughtful at that point. I find the respect they display is very moving. It shows that the human race is noble, in spite of everything.

Permalink 1 comment (latest comment by Cathy Lewis, Saturday, 19 Mar 2016, 18:52)
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