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Black Death Predated 'Small World' Effect, Say Network Theorists
KentuckyFC writes "Epidemiologists know that modern diseases can spread almost simultaneously in different parts of the planet because an individual who becomes infected in Hong Kong, for example, can infect friends in New York the following day. This is known as the small world effect. It is the same property that allows any individual to link to another individual anywhere in the world in just a few steps. But in the 14th century, the Black Death spread in a very different way, moving slowly across Europe at a rate of about 2 kilometers a day. Now network theorists have simulated this spread and say it is only possible if the number of long distances travelers in those days was vanishingly small. In other words, people in medieval society were linked almost exclusively to others nearby and so did not form a small world network. That raises an interesting question. If society in 14th century Europe was not a small world but today's society is, when did the change occur? The researchers say the finger of blame points to the invention of railways and steamships which allowed large numbers of people, and the diseases they carried, to travel long distances for the first time."
That's the most interesting question this makes you think of?
The study assumes people did not have long distance links. Alternatively, they had long distance links, but did not travel when they were infected with the bubonic plague.
Some people die at 25 and aren't buried until 75. -Benjamin Franklin
but it was just gas
Dave Matthews Band definitely spread diseases.
Dave Matthews Band
Um, no. It was originally done by Steve Miller (aka 'The Steve Miller Band').
This is either a horrible summary or a waste of research money. You're telling me that Eurpoean society in the 14th century didn't travel a whole lot?
Wow. Water *is* wet
um, wasnt that Steve "Guitar" Miller
The Bubonic plague was carried by the rats. It can only be transmitted human to human in it's final stages and the fleas can't survive long on human body. Two km a day seems about right for rats.
Boats have been around for thousands of years and move faster than the 2km per day spread the study shows.
From TFS:
Um, who exactly is this news to? Historians and sociologists have known this for decades.
The researchers say the finger of blame points to the invention of railways and steamships which allowed large numbers of people, and the diseases they carried, to travel long distances for the first time.
Or sick people didn't travel. Or the long-distance traveler stopped traveling after they became ill. Or a horse drawn cart didn't hold as many rats as ships or trains.
It would be neat to see a visualization of the spread of various diseases in our known history.
So it's true that I could catch some disease if I go out then?
Through extensive simulations I have discovered an important exception to the small world effect, which I call the Madagascar effect.
Roughly speaking, my theory states that diseases carried by travellers can spread quickly to anywhere in the world, except for Madagascar. If they shut down their harbors, you're fucked.
What if human beings were not, in some way, a vector?
[opening of "Survivors" from the 1970s]
I recommend they publish this in Duh: The Journal of the Insipidly Obvious. Does anyone really believe you need to be a medievalist to know that communication and travels was much slower in the middle ages than it is in the modern day? Simulations of how the disease spread are interesting from a historical point of view, but it's not even like we're talking about a time when humanity was on the cusp of "small world" connectiveness.
The "small world" nature of modern travel is a double edged sword. Yes, infectious diseases can spread rapidly and can quickly affect people over long distances, but because societies are constantly interacting with other societies, a large segment of the population is able to develop immunities to a large number of pathogens. When Europeans first came to the Americas, large numbers of the native populations were decimated by smallpox and other diseases. Because they had never been exposed to these diseases before and had no immunities built up to defend against it, a whole villiage would be wiped out within a short time. I have heard that far more Native Americans died from diseases this way than were ever killed during wars.
the small world effect is possible by low cost and fast transportation. The same holds true for tourism. So the intrepid British explorers who started early in the 18th century to roam all across Europe are the first indicators of this change. Look how old Thomas Cook (the company) is (Link: http://www.thomascook.com/thomas-cook-history/)
You know it's time for the next revolution when your rulers' names end with roman numerals.
...or the ones that survived the smallpox.
Laughter is the Spackle of the Soul.
\m/
Srry mates, it's friday...
-- 29A the number of the Beast
The rate of spread of the Black Death versus the rate of spread of other plagues at different times?
There's the third pandemic of the bubonic plague which spread from Pakhoi, China in 1882 to Hong Kong in 1894, then from (probably) Hong Kong to western India in 1896.
Pakhoi, China to Hong Kong is a pretty short distance, yet it took the plague many years to travel that route.
Hong Kong to western India is about 2,000 miles at the crow flies. Assuming it took exactly two years for the plague to travel that distance, it averaged about 3 miles a day.
So, was southern China a "small world" in 1882? How about Hong Kong and the ports of British India? I could see it being very likely that there was regular traffic between Hong Kong and British India, yet the plague traveled slowly between the two points. Perhaps the plague isn't as quickly traveling as human beings, for various unknown reasons.
My hometown (Weymouth, Dorset) has the dubious distinction of being the port where the black death entered England. Cool huh?
With the creation of planes, boats, trains, cars, and more and more improved versions every few decades, it becomes a much smaller world.
I won't be hard to imagine that in a century, people will have good friends _in another country_ and for that to be quite common.
"Just popping out to the friends mom.", 30 minute supergodliketurbomegaultra plane remix HD from one side of the planet to the other to hang out.
Hell, who knows, science might surprise us and we might even invent teleportation.
That is, the kind that doesn't clone and kill you, or maybe actually the kind that does clone and kill you, nobody will ever know since everything that gives you your external image as far as everyone else is concerned has been replicated, all that you are, all the memories, etc.
The only thing that might not be replicated is YOU specifically. It would be like a new session, a twin, not you. (sorry for that bomb of philosophical comments in 3...2...1)
Delay makes life difficult for diseases. I read once that in the era of sailing ships, immigrants to Australia from the UK tried to keep a cowpox infection going for the length of their voyage, passing it from volunteer to volunteer to bring the smallpox inoculation down under.
Try though they might, they weren't successful. The voyage was simply too long. Now the same trip might take about a day. It's a different world.
Ships spread infested rats from port to port. So it was a small world network in the technology of the day.
Did they factor in other vectors? Birds, weather, insects etc.
"If any question why we died, Tell them because our fathers lied."
I wonder how today's societies would react to the modern day equivalent of one of these plagues.
"If any question why we died, Tell them because our fathers lied."
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
You mean to say that the jet set didn't exist in the 14th century? But how did the elite socialites ever find each other??!!!!!
Passenger airline traffic has the potential to disperse a world wide plague more deadly than all past wars combined. It is another issue which is shrouded by deliberate blindness as the cure would be very disruptive.
Here in Washington state at one point there was a study which put tags on salmon hatchlings and asked people to report where they found the tag. One was found in a tree In New Zealand. The conclusion was that a bird had a snack during its annual migration. Humans aren't the only vector for long distance infection. In medieval times birds probably beat ship going rats for speed of global transmission.
England was also Feudal at the time, meaning most people were tied to the land. Most didn't have freedom of movement even if they wanted to visit other areas, marry in other areas, or visit relatives who had, there were none. So that kind of cramped movement too. There was a small world effect.. disease would spread like wildfire around your own town.
Almost nobody had horses back then, compared to the 19th century. Working the land was done manually, or with the aid of oxen and such. Horses were more or less used as battle transportation and sometimes very important couriers. There was occasional other use for them, but horse ownership was usually reserved to the nobility and rich cities due to the cost of maintenance in the times that the black plague was hitting Europe.
Keep in mind that the black plague was spread by fleas that favoured rats, cats, dogs and such as hosts. They would choose humans as hosts, but were repelled by horses and their smell. As such, people that lived in horse staples and worked with horses, or rode them to the next town, most often were spared. If a lone person travelling on horse back would come from an infested city and was not bitten by an infested flea by the time he left that city, he wouldn't be carrying any infested fleas or the bacteria by the time he arrived in the next town. The spread of the virus might have actually occurred without any human interaction whatsoever in a lot of cases where fleas just infected rodents living in the wild, or actually by people that travelled by foot and brought their dogs and such along.
I was promised a flying car. Where is my flying car?
The question is not whether some people traveled long distances. The question is whether they did it *quickly*.
If people are traveling sufficiently slowly that they cannot cover a long distance before the disease becomes noticeable/disabling then the disease will not travel quickly. What spreads diseases quickly today is that one can contract a disease and then travel to a distant location before the disease becomes noticeable.
So yes, while there were long-distance trade routes in the 14th century, they took a sufficiently long time to traverse that people who contracted a disease either stopped their traveling, or were avoided by others, before they had traveled very far. Therefore, the diseases spread more slowly.
And yes, obviously it was the advent of rapid transport mechanisms, such as trains and steam engines, to started moving people fast enough that they could travel a significant distance before a contracted disease would manifest itself.
We've known this for quite some time. The only people who travelled any distance were merchants. Nobility had horses and moved around their country, though normally from the capital to their province, and the average person might make a couple long distance trips in their lifetime, (including crusades, which was typically one trip down and one trip back). A lot of surnames came from the guy who moved from one town over.
Imagine how increased leisure time and affordable long-distance travel could somehow increase the world's interconnectivity. IT'S IMPOSSIBLE!11!!1
Before the pathological evil of what we know as the industrial war machine, with broadcast technologies and deployment tactics that could harness fear and loathing to politics everywhere at once--- and the tireless drudges who worship them came to the fore---
We were becoming increasingly cyclical, distracted by moment, swaying in tighter rhythms while not dancing -- a bad sign. Hypnotized by the leafspring, the mainspring, the ratchet, the pendulum and most obnoxious of all, an hour-bell that means something besides nothing.
Between brutal wars -- merely pathological, in a cute sort of way. The animals kept us sane.
Despite ages of civilized existence -- it has scarcely been one hundred years since our clocks and calendars, biological and practical, were last paced by animals. And what a time it has been.
Rome built the roads; but it was always horses and oxen that set the pace. Oxen and people, measured seasons of growing in the fields. Even on the ocean do we find animal companions, for in the days when sails took us to places unknown, animals were aboard to ensure survival. But the wind itself is like an ox, with moods that paced the journey.
History has always moved in waves legions of soldiers traveling light and fast as wind, settlers burdened with goods at a snail's or oxen-pace. On a smart strong horse riders could doze and daydream, the beast's eyes as fixed on the horizon as the rider. In the far north dogs, rivers and caribou set the pace; in Summer mosquitoes kept everyone on the run.
Was a time we'd foretell the seasons by the birds as they got ready to travel, there were places for them to roost. Migrating birds and the moon and the stars to guide them were featured in theaters of sky and morning and evening and darkest night.
People cast tiny flickering shadows on land that went out with sleep -- not the lidless throbbing glimmer of busy continents today.
And news flowed like the tides -- news from over the ocean, of country and world gathering in eddies of pulp presented, like sermons, in their own time and place of reading. Local news and affairs churned with comfortable babbling regularity: ripples of gossip, stories heard in tavern and meeting-house and church. Rumor from afar came through with strangers and gathered rapt attention for telling and re-telling. Church it was that harnessed the calendar at first -- but it took a whole week for the tides of morality to flow round again -- plenty of time left for fun.
Where days full of task might stretch a bit here and there played themselves out, church bells gave us the first hint of regimentation to time. A manageable affair, for even old rural school-house days could hold more leisure within the hours, and there was more mixing between the ages during the process of learning. Apprenticeships. Though even in the age-segregated electric-bell'd warrens of today a good teacher can still open vistas; but like all modern animals even teachers are challenged by pace and environment. They're only human.
Even our busiest cities were townish -- wide avenues for horses, slow moving newspapers and the ever-present lure to market-place, wharf and concert hall tugged at us, kept us moving between meetings.
Those on long journeys tended to be out in the open. They set sights on destination more so than the calendar; getting there was the thing even if the journey was not. And long many-people journeys were actually moving cities -- where one or two people drift into dream-time, whole families and groups illuminated the trail with their own culture and hobby. We sang along the rivers, played music in time with horses' hooves. Children sought adventure on the fringes of camp.
Weather was the ocean we lived in, not the comforting or annoying visitor it is today. If you spot people-dots in a model of society you'll find us traveling more distance but moving around less than ever before. Everything is piped in, even things that shouldn't have been.
Farms have be
<blink>down the rabbit hole</blink>
...the Black Death.
The plague marked the begining of the end of the feudal system (at least in Western Europe). Due to the shortage of agricultural workers, peasants were no longer serfs, effectively owned by a landowner. They could (and did) migrate in search of better pay & conditions.
Sailors, seasonal workers, miltary movements, the great seasonal markets, etc. Medieval Europe isnot rural America.
The Black Death was spread by rats, fleas on rats to be precise, not so much person to person. So 2 km per day might be about as fast as the rate of rat travel in 14th century Europe. (Rather rat to rat to fleas to humans travel... or whatever)