Ship's rats preserved in tar since 1373. Analysis of Black Death bacterium.

Scientists hope to be able to found out which variant of the Black Death bacterium caused one of the deadliest pandemics in human history. They have discovered two rats preserved in tar in a shipwreck recently uncovered in Estonia.

The date of 1373 is ideal because that is in the middle of the era of the Black Death in Europe. The scientists want to find out the variant of the bacterium which killed so many people. You may remember that at the time people thought that cats spread the disease but it was humans (see below) so by killing the cats they made things worse. However, it is a myth that there was a mass culling of cats.

The discovery of this ship containing two preserved rats is revealed in the second episode of the Channel 4 series Bettany Hughes' Treasures of the World. It will be aired on April 13.

Image created by the masterful DALL-E. 

Bettany Hughes said that she heard about the unbelievable discovery of the ship and she told The Times (the source of the story for me): "It's the biggest archaeological maritime find on land ever. Then, a few months before we were due to be filming in Estonia, we heard about this incredible discovery of the rats. A barrel of tar had fallen over and mummified them. So they have been preserved in tar. You don't get organic material like that preserved from the fourteenth century. It's almost unheard of."

She added that, "It's the first time we've got a potential candidate for the Black Death carrier. It's bang on the absolute peak of the Black Death surge in Europe, so it would be extraordinary if the rat turns out not to have it."

They've already analysed their hair and stomach contents. The stomach contents would also tell us about the diet of the sailors on the ship at the time.

They hope that the rats test positive for the bubonic plague and if so they will be able to discover the variant that caused the pandemic.

It's believed that the ship was part of a powerful trading network called Hanseatic League. It was discovered in 2022 during construction work in Tallinn, the capital of Estonia.

The area was once underwater. The ship had sunk close to the mouth of the River Harjapea.

The ship has overlapping planking, sealed with animal hair and tar. "We have found wool material used for packing, we have also found some tools and fragments of mediaeval leather shoes." - Bettany

The Bacterium

The Black Death, a devastating pandemic that swept through Europe during the 14th century, claimed an estimated 25 million lives between 1347 and 1351. Historically, rats have been blamed for spreading this deadly disease. However, recent research challenges this assumption.

Yersinia pestis, a bacterium, is the culprit behind the Black Death. In 1894, bacteriologists Kitasato Shibasaburo from Japan and Alexandre Yersin from France independently identified this pathogen. They discovered that it was carried by fleas, which acted as parasites on both rats and other small rodents ¹. These infected fleas, in turn, sought out and bit humans, transmitting the disease.

Contrary to popular belief, rats weren’t the primary carriers of the plague. Instead, it was humans who facilitated its spread. Simulations conducted by researchers revealed that the model focusing on fleas and ticks on humans best explained the disease’s transmission in European cities. The plague moved too swiftly for rats to be the sole culprits. If rats were the main cause, we would expect more archaeological evidence of dead rats, but historical and archaeological records provide little support for this claim ².

So, while rats play a role in the Black Death narrative, it was ultimately human interactions that allowed the bacterium to wreak havoc across the continent. The fleas, hitchhiking on humans, acted as the bridge between rodents and people, leading to one of the most devastating pandemics in history.

Today a simple course of antibiotics cures the Black Death. This critically important drug was unavailable at the time.

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P.S. please forgive the occasional typo. These articles are written at breakneck speed using Dragon Dictate. I have to prepare them in around 20 mins.