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Why did the Plague spare Poland?
The Black Death skipped certain parts of Europe - and that could be a lesson for today's coronavirus epidemic
- Calm down, we're not comparing COVID-19 to the Plague.
- Well, not literally. But this map raises an interesting question: Why were some parts of Europe spared of the Black Death?
- And can that tell us something about where the coronavirus will or won't spread?
The doctor will see you now
Engraving of 'Doctor Schnabel' ('Dr. Beak'), a plague doctor in 17th-century Rome, wearing the typical mask with which caregivers sought to keep the 'bad air' at bay that they held responsible for the spread of the disease.
Image: Paulus Fürst, ca. 1656 - public domain
The Black Death was a ruthless killer – and, if you were lucky, a swift one. Its more fortunate victims "ate lunch with their friends, and dinner with their ancestors in paradise," wrote Giovanni Boccaccio, who lived through the initial wave of the Plague as it struck Italy in the 1340s.
What does that have to do with the coronavirus? Not a whole lot, fortunately. Except that the brief of this little corner of the internet is to look for strange maps, and one map led to another.
The Plague was brought from China to Europe in the 1330s by rodents hitching rides with traders. The infection with the Yersinia pestis bacterium was typically transmitted to humans by fleabites. The Plague's three manifestations were bubonic (causing painful swellings), septicemic (infecting the bloodstream) and pneumonic (choking off breathing, and transmittable via coughing). Left untreated – as was necessarily the case in the Middle Ages – bubonic plague had a mortality rate of about 50%, for the other two, it's virtually 100%.
Bocaccio's Italy was hit hard by the epidemic. Cities like Venice and Pisa lost three-quarters of their population. The disease followed the traditional trading routes north, racing forward each spring as a new generation of fleas was ready to spread the infection.
The Plague afflicted most of Europe in a relatively brief period. It's estimated that it killed as many as 25 million – a third of Europe's population at the time – in just five short years.
Absent explanations and remedies, Europe's populations turned to God for hope, and victimized outsider groups as scapegoats. Some of Western Europe's worst anti-Jewish pogroms before WWII took place during outbreaks of the Plague.
In just a few years, the Plague had moved from its entry points on the Mediterranean as far north as Scandinavia.
Image: Andy85719 - CC BY-SA 3.0
This map shows the progress of the Plague, from its arrival in the Mediterranean:
- First afflicted (in 1347) were Asia Minor, and the islands of Sicily, Sardinia and Corsica, with just small bridgeheads on the European mainland: Marseilles and environs, Calabria (the tip of Italy's shoe), and the southern shore of what is now Turkish Thrace (i.e. European Turkey).
- By the next year (1348), the disease had achieved a firm foothold in Europe, reaching as far as the gates of Toledo and Paris.
- In early 1349, the Plague had overwhelmed London and Frankfurt, and was poised to pounce Vienna and Bucharest. Later that year, it reached as far as Ireland and Norway.
- Its relentless march north continued. In 1350, it hit Lübeck and Copenhagen, reaching high into Norway. In 1351 and thereafter, it swept further north, touching the entire continent.
But as this map indicates, the Plague spared certain areas (marked green on the map) on march of destruction:
- an area in Italy centered on Milan;
- small, contiguous parts of Spain and France, on either side of the Pyrenees;
- an area in the Low Countries around Bruges;
- a large area in Eastern Europe, stretching from Magdeburg to beyond Warsaw, taking in most of present-day Poland, plus some surrounding areas.
Why? First off, the map is slightly misleading. Green does not mean 'safe', just 'less deadly'. Milan, for example, only lost about 15% of its population. Horrific by today's standards, but a mere trifle compared to the almost wholesale extinction of Italy's other cities. In Poland and the other 'green' areas too, people did die of the Plague, albeit in much lower numbers than elsewhere.
Blues vs. Greys
Interconnected equals infected, and vice versa.
One main reason why Poland escaped relatively unscathed, was the decision by Poland's king, Casimir the Great, to close the country's borders – and set up internal quarantines.
This increased Poland's natural isolation, both from the outside world and between the settlements within the country – generally smaller and less connected than elsewhere in Europe. Prague to Krakow took eight days on horseback. People infected took between 24 to 72 hours to get sick. So the issue would 'resolve' itself well before the danger reached the Polish border.
Isolation plus quarantine certainly helped spare Poland from the worst of the epidemic. One more spurious explanation is that Poland had more cats than other parts of Europe, and thus less disease-carrying rats…
Milan's significantly lower mortality rate may also be down to the city's stricter quarantine measures: The houses of infected families were simply bricked up (with the infected left to die inside).
Like Poland, the French-Spanish area, corresponding to the then-kingdom of Navarre, may have benefited from its relative isolation. Why the area around Bruges – then a thriving port with connections to the Mediterranean – might have been spared, is more of a mystery.
So, what's the lesson, if any? Isolation definitely helps against infectious diseases. But that's about the only advantage of being isolated. Take this map of the spread of COVID-19 as of 11 am on 5 March. If you had to divide the world into 'fun' and 'no fun' halves, they would correspond quite well with the blue and grey zones on this map, respectively.
For example, one sure-fire way to limit your exposure to the outside world is to have a bloody civil war – see Yemen, Libya and Syria. Another is to be a destination as out of the way and unconnected as Paraguay, the Central African Republic or Mongolia.
If it's the price of living in an interconnected world, then perhaps there are worse things than having to fight off a slightly deadlier iteration of the flu. Praise globalization and pass the hand sanitizer – with your elbows, please!
Strange Maps #1014
Got a strange map? Let me know at firstname.lastname@example.org.
Evolution doesn't clean up after itself very well.
- An evolutionary biologist got people swapping ideas about our lingering vestigia.
- Basically, this is the stuff that served some evolutionary purpose at some point, but now is kind of, well, extra.
- Here are the six traits that inaugurated the fun.
The plica semilunaris<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgwMS9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY3NDg5NTg1NX0.kdBYMvaEzvCiJjcLEPgnjII_KVtT9RMEwJFuXB68D8Q/img.png?width=980" id="59914" width="429" height="350" data-rm-shortcode-id="b11e4be64c5e1f58bf4417d8548bedc7" data-rm-shortcode-name="rebelmouse-image" />
The human eye in alarming detail. Image source: Henry Gray / Wikimedia commons<p>At the inner corner of our eyes, closest to the nasal ridge, is that little pink thing, which is probably what most of us call it, called the caruncula. Next to it is the plica semilunairs, and it's what's left of a third eyelid that used to — ready for this? — blink horizontally. It's supposed to have offered protection for our eyes, and some birds, reptiles, and fish have such a thing.</p>
Palmaris longus<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgwNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzMzQ1NjUwMn0.dVor41tO_NeLkGY9Tx46SwqhSVaA8HZQmQAp532xLxA/img.jpg?width=980" id="879be" width="1920" height="2560" data-rm-shortcode-id="4089a32ea9fbb1a0281db14332583ccd" data-rm-shortcode-name="rebelmouse-image" />
Palmaris longus muscle. Image source: Wikimedia commons<p> We don't have much need these days, at least most of us, to navigate from tree branch to tree branch. Still, about 86 percent of us still have the wrist muscle that used to help us do it. To see if you have it, place the back of you hand on a flat surface and touch your thumb to your pinkie. If you have a muscle that becomes visible in your wrist, that's the palmaris longus. If you don't, consider yourself more evolved (just joking).</p>
Darwin's tubercle<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgxMi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0ODUyNjA1MX0.8RuU-OSRf92wQpaPPJtvFreOVvicEwn39_jnbegiUOk/img.jpg?width=980" id="687a0" width="819" height="1072" data-rm-shortcode-id="ff5edf0a698e0681d11efde1d7872958" data-rm-shortcode-name="rebelmouse-image" />
Darwin's tubercle. Image source: Wikimedia commons<p> Yes, maybe the shell of you ear does feel like a dried apricot. Maybe not. But there's a ridge in that swirly structure that's a muscle which allowed us, at one point, to move our ears in the direction of interesting sounds. These days, we just turn our heads, but there it is.</p>
Goosebumps<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMxNC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNzEyNTc2Nn0.aVMa5fsKgiabW5vkr7BOvm2pmNKbLJF_50bwvd4aRo4/img.jpg?width=980" id="d8420" width="1440" height="960" data-rm-shortcode-id="8827e55511c8c3aed8c36d21b6541dbd" data-rm-shortcode-name="rebelmouse-image" />
Goosebumps. Photo credit: Tyler Olson via Shutterstock<p>It's not entirely clear what purpose made goosebumps worth retaining evolutionarily, but there are two circumstances in which they appear: fear and cold. For fear, they may have been a way of making body hair stand up so we'd appear larger to predators, much the way a cat's tail puffs up — numerous creatures exaggerate their size when threatened. In the cold, they may have trapped additional heat for warmth.</p>
Tailbone<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMxNi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3MzQwMjc3N30.nBGAfc_O9sgyK_lOUo_MHzP1vK-9kJpohLlj9ax1P8s/img.jpg?width=980" id="9a2f6" width="1440" height="1440" data-rm-shortcode-id="4fe28368d2ed6a91a4c928d4254cc02a" data-rm-shortcode-name="rebelmouse-image" />
Image source: Decade3d-anatomy online via Shutterstock<p>Way back, we had tails that probably helped us balance upright, and was useful moving through trees. We still have the stump of one when we're embryos, from 4–6 weeks, and then the body mostly dissolves it during Weeks 6–8. What's left is the coccyx.</p>
The palmar grasp reflex<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMyMC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjY0MDY5NX0.OSwReKLmNZkbAS12-AvRaxgCM7zyukjQUaG4vmhxTtM/img.jpg?width=980" id="8804c" width="1440" height="960" data-rm-shortcode-id="67542ee1c5a85807b0a7e63399e44575" data-rm-shortcode-name="rebelmouse-image" />
Palmar reflex activated! Photo credit: Raul Luna on Flickr<p> You've probably seen how non-human primate babies grab onto their parents' hands to be carried around. We used to do this, too. So still, if you touch your finger to a baby's palm, or if you touch the sole of their foot, the palmar grasp reflex will cause the hand or foot to try and close around your finger.</p>
Other people's suggestions<p>Amir's followers dove right in, offering both cool and questionable additions to her list. </p>
Fangs?<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Lower mouth plate behind your teeth. Some have protruding bone under the skin which is a throw back to large fangs. Almost like an upsidedown Sabre Tooth.</p>— neil crud (@neilcrud66) <a href="https://twitter.com/neilcrud66/status/1085606005000601600?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Hiccups<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Sure: <a href="https://t.co/DjMZB1XidG">https://t.co/DjMZB1XidG</a></p>— Stephen Roughley (@SteBobRoughley) <a href="https://twitter.com/SteBobRoughley/status/1085529239556968448?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Hypnic jerk as you fall asleep<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">What about when you “jump” just as you’re drifting off to sleep, I heard that was a reflex to prevent falling from heights.</p>— Bann face (@thebanns) <a href="https://twitter.com/thebanns/status/1085554171879788545?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script> <p> This thing, often called the "alpha jerk" as you drop into alpha sleep, is properly called the hypnic jerk,. It may actually be a carryover from our arboreal days. The <a href="https://www.livescience.com/39225-why-people-twitch-falling-asleep.html" target="_blank" data-vivaldi-spatnav-clickable="1">hypothesis</a> is that you suddenly jerk awake to avoid falling out of your tree.</p>
Nails screeching on a blackboard response?<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Everyone hate the sound of fingernails on a blackboard. It's _speculated_ that this is a vestigial wiring in our head, because the sound is similar to the shrill warning call of a chimp. <a href="https://t.co/ReyZBy6XNN">https://t.co/ReyZBy6XNN</a></p>— Pet Rock (@eclogiter) <a href="https://twitter.com/eclogiter/status/1085587006258888706?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Ear hair<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Ok what is Hair in the ears for? I think cuz as we get older it filters out the BS.</p>— Sarah21 (@mimix3) <a href="https://twitter.com/mimix3/status/1085684393593561088?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Nervous laughter<blockquote class="twitter-tweet" data-lang="en"><p lang="en" dir="ltr">You may be onto something. Tooth-bearing with the jaw clenched is generally recognized as a signal of submission or non-threatening in primates. Involuntary smiling or laughing in tense situations might have signaled that you weren’t a threat.</p>— Jager Tusk (@JagerTusk) <a href="https://twitter.com/JagerTusk/status/1085316201104912384?ref_src=twsrc%5Etfw">January 15, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Um, yipes.<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Sometimes it feels like my big toe should be on the side of my foot, was that ever a thing?</p>— B033? K@($ (@whimbrel17) <a href="https://twitter.com/whimbrel17/status/1085559016011563009?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Are we enslaved by the finer things in life?
- The Roman writer, Tacitus, argued that the Roman Empire was built by enslaving conquered people who became accustomed to fine living and luxury.
- Technology today has become so essential to our daily lives that it seems impossible to break free of it. It's as much a cage as a luxury.
- Being dependent on a thing gives it power over you. To need something or someone is, for better or worse, to limit yourself.
- There was a massive die-off of marine life 359 million years ago, and nobody knows why.
- A new study proposes that the Late Devonian extinction may have been caused by one or more nearby supernovae.
- The supernova hypothesis could be confirmed if scientists can find "the green bananas of the isotope world" in the geologic record.
Fifty years of research on children's toy preferences shows that kids generally prefer toys oriented toward their own gender.