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."

Comments

Long distance travel

[schneidafunk]

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.

Re:Long distance travel

[Ultra64]

>Alternatively, they had long distance links

Do you know of some secret mode of transportation that has been lost to historians?

Re:Long distance travel

[schneidafunk]

You mean like horses?

Re:Long distance travel

[rubycodez]

and rats like ships

Re:Long distance travel

[Richy_T]

Though it would seem likely that some of the spread was due to traveling to get away from the plague when one was (unwittingly) infected with it.

Re:Long distance travel

[Mobster75]

I would suspect the major factor back then on why the plague didn't spread so far, so quickly was that while they had long-distane trade links, the time period during which the plague would incubate and ultimately kill someone was far shorter than the time it took to travel great distances. I'm sure that if someone in a travel party began exhibiting symptoms of the plague, they were rather quickly left to die on their own in some remote location to avoid infecting the rest of the party.

Re:Long distance travel

[Ultra64]

Yes. Thank you people, I know about ships and horses.

Explain how a person with bubonic plague is going to survive traveling long distances on one of those.

Re:Long distance travel

[Sarten-X]

Horses are expensive to maintain, and have a rough daily limit of about 30 miles. In comparison, a human walking at 3 mph can go the same distance in only 10 hours. The difference, of course, is that horses can carry more and get there faster, before taking more time to rest.

For the peasants who made up the majority of the population during the 14th century, a horse was a good tool for farmers or messengers, but regular travel would best be done on foot with a light pack and a steady pace.

Re:Long distance travel

[Anonymous Coward]

Exactly! Don't you idiots learn anything about history in school? People travel for long distances all the time in World of Warcraft and Game of Thrones, and those are both fairly realistic depictions of the 14th century.

Re:Long distance travel

[icebike]

You have to evaluate the transit time required via any given mode of transportation, compared to the time it takes to incapacitate a person after initial infection.

That limits the distance a lone carrier could spread the disease. People going to the next village to trade, or (once the danger becomes apparent) to request help or warn them would be the likely rural vectors, and that sounds like the two km / day limit. People could obviously walk farther in a day, but didn't need to. The next village or settlement was the extent of their every-day wandering).
That assumes foot traffic as the default mode of transportation.

However when horses became affordable for everyday travelers, as well as wagon freight transport, and carriage travel became common between villages, you would expect that distance could be pushed out to 18 to 25 miles per day. Either on horseback or by carriage or wagon, it was typical to cover about that distance in a day.

This would be the first time non-human disease carriers (rats) would become a significant vector, as wagon cargo could deliver rats, dead or alive, over distances of 100 miles or more in 7 or 8 days.

So I don't believe you have to postulate the existence of rail travel to see much wider spread over the gestation period. All you need to is assume some goods might be transported (in bulk big enough to accidentally include rats) over several days of journey. Rats in cargo, even if dead, would typically arrive at their destination regardless of how long the trip took. and 7 or 800 miles would not be unreasonable in harvest times.
 

Re:Long distance travel

[Anonymous Coward]

This could actually speed the spread, if people fled while not realizing it was rat fleas that carried the plague. Plague-stricken victims don't get far, but people with fleas & flea eggs in their clothing trying to get away from the Black Death can.

I don't know if this particular reaction was a contributing factor in the spread, however.

Re:Long distance travel

[icebike]

Ships can deliver rats a long distance. As can wagon loads of produce.

Re:Long distance travel

[damienl451]

There are other ways that the plague could spread. Yes, someone infected with the plague would die before reaching their destination. However, ships also carried cargo, which could be contaminated. Standard procedure was to quarantine ships and their cargo but, understandably, there could be pressures to rush things because people didn't like their precious fabrics to be kept on an isolated island for forty days, especially since they could easily get damaged in the process.

This is how the Great Plague of Marseilles began: a ship laden with cargo belonging to important people was not quarantined according to procedure. Unfortunately, it had come from the Middle East where the plague was rampant and it starting spreading through the city.

Re:Long distance travel

[H0p313ss]

Rats

Re:Long distance travel

[Optali]

Don't forget "the ship" another mythical contraption

Re:Long distance travel

[Optali]

Very good point.
And sum to it that people had a very good reason to do that as many laborers mved from place to place for the harvests.

Here in Central Europe young men used to travel long distances during their time of apprenticeship in the different guilds, this tradition is still held in Germany (Wanderschaft). Guilds like the stonemasons travelled from Spain to Cenral Europe and you can find their guild emblems in Romanic and Gothic buildings across the whole continent. Some may even have been in Africa with the Arabs during the period of Al Andalus.

Re:Long distance travel

[Optali]

Fuck mate, but that's only newbs until they get a decent flying mount.

Re:Long distance travel

[Optali]

Tell that to Ghengis Khan.

Re:Long distance travel

[Optali]

Incubation period?

And note that the fact that the Black Plague was actually the bubonic pest is not yet confirmed, we can't thus be sure if there may have been people infected with the plague while being asymptomatic.

 

Re:Long distance travel

[Optali]

The problem with rats is that they tend to be more sedentary than humans.
Modern bubonic pest (endemic in some parts of India until recent times) has only been able to infect small numbers of people, despite a much higher population density and a similar degree of (in)salubrity.

Birds maybe? (if the Plague was not the bubonic pest, as we know it at least)

Re:Long distance travel

[MightyYar]

But surely it would fall off of the edge of the earth! Dragons!

Re:Long distance travel

[Shinobi]

Even up until WW2, the horses were what limited the rate of advance for armies, including the german invasion of Belgium and France, since horses were what pulled the majority of the logistics train.

Also, in regions where roads were not common, or in VERY bad shape, you usually had no horse depots, meaning that humans were much faster, especially over broken terrain

Re:Long distance travel

[khallow]

Horses are expensive to maintain, and have a rough daily limit of about 30 miles. In comparison, a human walking at 3 mph can go the same distance in only 10 hours.

That's not comparable. The horse could do that forever (for example, see this US cavalry manual which stipulates cavalry can go 35 miles a day, six days a week indefinitely - page 152) while the person would not be able to maintain that sort of pace for more than a few hours to a day unless they were in really good shape.

In comparison, typical indefinite marching rates for an army were about 10 miles a day (both for roman legionaires and US soldiers).

Re:Long distance travel

[Optali]

Maybe.

And I don't really understand the whole point of the study... if people weren't able to travel far they did not infect too many others... yet the plague wiped Europe clean, Wikipedia says it killed 75-200 million people... in 2 years !!!

So... what's the point of the study then?

Re:Long distance travel

[dpilot]

> but did not travel when they were infected with the bubonic plague.

Or at least not far. Any idea what the incubation time of the plagues were, or how that time compared to how long a trader would spend in one market before moving to the next? In other words, were they in one spot long enough to get infected and start showing symptoms before they would have been scheduled to move on.

Another thought... Someone once wrote about mapping plague outbreaks to elevation in London - really to river and sewer rats carrying the fleas that carried the plague. There is a preference to make roads follow higher ground, to avoid getting mired. Traders might have generally accidentally avoided the plague because of this.

As for shipping, you probably couldn't go far before falling sick with the plagues, so this might be one more cause for shipping loss back then.

Re:Long distance travel

[Quasimodem]

IIRC the incubation period between exposure and first symptoms of bubonic plague is approximately six days, which would mean a determined walker could cover over 100 miles spreading his disease wherever he stopped to eat, converse, and sleep. Retarding that spread would be the fact that most travelers were not traveling any great distance. Serfs and peasants were tied to the land, seldom traveling further than the nearest market, but there were peddlers, pilgrims and couriers, as well as the upper classes and their servants, who were more mobile.

All things considered, two miles a day does not seem too unbelievable a pace if the disease was spread by human vectors. And yes, of course, railroads and steamships were the catalyst for the great nineteenth century human migrations and, naturally, their diseases.

Re:Long distance travel

[swb]

I've read that most of the road network in Europe at this time was originally built by the Romans and Roman armies would basically build a fort at the end of every day's march; these forts would be the basis of towns along the road. This meant that the nearest village was basically a day's walk.

I would argue that they didn't have much reason to travel even to the next village. At best they would trade for agricultural products or craft goods they didn't have or have enough of (pottery, animals, wood goods, ground flour maybe, wine or beer). There really wasn't anything else to buy even if they had gold because they wasn't that much else made.

It really wasn't a consumer products society. People made what they needed.

Re:Long distance travel

[icebike]

That sounds reasonable. So how far apart did they build them?

As north america was being settled, horses were in wide use, by every household. Walking was less of an influence.

The average distances between towns averaged 18 miles, the distance you would want to travel on horseback per day. Someone did some research on the distances horses could cover in a day, given the conditions of un-improved trails and found that pretty much agreed with historical records of the location of Roadhouses, which tended to spring up near where common camp sites were, and towns sprung up around the Roadhouses.

This distance, variable by type of terrain, held true as settlement progressed all the way across the continent, EXCEPT for those towns that sprung up along rail lines through mostly un-populated territory. Those tended to spring up near spaced to where steam engines needed to replenish their water and fuel.

So even in Washington, Oregon, and California, towns tended to be on average 18 miles apart. Roadhouses would spring up at that distance, supplies would be transported that far, and stores would appear.

Re:Long distance travel

[rasmusbr]

People have traveled long distances for thousands of years and the way to do it has always been by boat. It turns out that rowing is typically more effective than walking and horseback riding even if the land route is shorter. This is especially true if you assume that the main purpose of the trip is to carry cargo (or loot...).

If you were a young man born and raised near the coast in the bronze age odds are you would end up travelling hundreds of kilometers/miles from home at least once in your life, perhaps as an oarsman for someone who was wealthy enough to own a small boat.

Now for some of my own speculation, I would hypothesize that once sailing was invented and spread across Europe it would have become increasingly unprofitable to row, which then meant that the barrier to entry into meaningful boat ownership would have been raised significantly (a small and simple row boat v.s. a large and complex sail boat) to the point where the only ones travelling long distance were people who were specializing in sailing and trade. It seems reasonable to assume that the average coastal-dwelling man in the bronze age saw more travel than the average coastal-dwelling man in the middle ages. Of course, if you take into account that populations spread further inland between the bronze age and the middle ages it becomes obvious that people must have become more stationary.

Re:Long distance travel

[radarskiy]

"did not travel when they were infected with the bubonic plague."

Mostly irrelevant, since bubonic plague is only rarely transmitted directly from human to human.

The typical vectors is healthy animals (including humans) carrying the infected fleas around.

Re:Long distance travel

[Wycliffe]

Horses are expensive to maintain, and have a rough daily limit of about 30 miles. In comparison, a human walking at 3 mph can go the same distance in only 10 hours.

That's not comparable. The horse could do that forever (for example, see this US cavalry manual which stipulates cavalry can go 35 miles a day, six days a week indefinitely - page 152) while the person would not be able to maintain that sort of pace for more than a few hours to a day unless they were in really good shape.

In comparison, typical indefinite marching rates for an army were about 10 miles a day (both for roman legionaires and US soldiers).

It's very comparable. A human can keep up a 3mph walk forever as well. A 3mph pace is not hard for a human at all and without
a pack 30 miles a day would not be an issue for a human. 35 miles per day, six days a week indefinitely would not be a problem for
the average person either. I don't think a march with camp setup, etc... is comparable to what the original poster was talking about.
I think you underestimate what a human is capable of. When I was in college we went on a hike to the bottom of the grand canyon
for a week. None of us were in great shape, did any training, or probably near as fit as a peasant who worked all day in the field
every day yet we averaged about 20-25 miles a day for a week with heavy packs on rough terrain and making camp each night.
We obviously could have done alot more with a light pack. And again, we were not in shape, didn't train, and most had never even
been backpacking before. For endurance running a human is every bit as good as a single horse. The pony express used multiple
horses because horses are faster over short distances but over multiple days a human is actually faster. A good runner can do alot
more than 35 miles per day. This guy averaged over 50 miles a day for 40 days:
http://www.outsideonline.com/blog/outdoor-adventure/the-human-express-interview-with-karl-meltzer.html
Here is one of many articles that states that humans can outrun every animal on the planet:
http://discovermagazine.com/2006/may/tramps-like-us

Re:Long distance travel

[Sarten-X]

3 MPH is a typical hiking speed. Hiking 10 hours isn't terribly hard, even with a light pack. Armies, especially legionnaires and modern soldiers, do not carry light packs. They carry about 50 lbs or more.

Horses are really beasts of burden, not suitable for speed. In 14th century Europe, they were most useful for trading caravans, whose profit was based on how much they could carry in one trip. They were also useful for nobles, who had to carry all of their regalia. It'd be pretty hard for anybody else to justify the expense of buying a horse just to carry more while traveling.

Re:Long distance travel

[Wycliffe]

Oh, and reading over that article about Karl Meltzer, it says on the 40th day he ran over 100 miles.
I'm not sure a horse is even capable of 100 miles in a single day where here is a person who
did this after running over 2000 miles in the previous 39 days.

Re:Long distance travel

[cusco]

Wagon freight and carriage travel didn't become common until the late-7th/early-18th century, as the Roman road system had collapsed from lack of maintenance and was never repaired outside of urban areas. It wasn't until later than that when horses became common, and really the late 19th century before riding horses became widely available to anyone beyond the aristocracy.

Re:Long distance travel

[icebike]

Yes, but much of Europe is served by river and canals, and has been for a long time before rail came into existance.

Most of the canals began construction in the 16th century in some parts, and really took off in the 19th.
But rivers were the highways, an Europe has many long rivers that cross borders, and goods transport on them was bound to include rats.
Further it was easy, so even mildly sick people could use this means.

Re:Long distance travel

[lennier]

But surely it would fall off of the edge of the earth! Dragons!

Nah, dragons are okay for reconnaissance and town defense, but they're less cost-effective than ships for long-haul cargo transportation.You want leviathans, or krakens.

Re:Long distance travel

[Capt.Albatross]

Right. The authors have overlooked the fact, as shown by their own map, that, in 1347, the plague moved into Europe along a broad front: the Mediterranean coastline. I imagine that it spread along that front by ship, a good deal faster than the inland spread that the authors base their thesis on.

Furthermore, the authors summarily dismiss the effect of the disease on its spread. It was very debilitating, and a traveller on land who fell sick would be unlikely to continue his journey. The authors exaggerate the distance a sick traveller would be likey to spread the disease.

Add to this the failure of the authors to recognize that almost all land travel would be by foot (with what animals were being used for transport mostly being used to carry the baggage of foot travellers) and you have three strikes against their argument. I don't doubt that the world was less connected than than it is now, but the authors overstate their case. By overestimating the rate at which land travel would, in practice, spread the diseease, they have underestimated the amount of travel.

Re:Long distance travel

[cusco]

True enough, but by that time the Black Death had already swept through Europe several times. Travel has improved by orders of magnitude over the last few centuries.

Re:Long distance travel

[Half-pint HAL]

Actually, someone's now suggesting the "Roman" roads actually predated the Romans. I'd be tempted to dismiss this as another wild theory in search of fame, but it fits with the general trend in history: after centuries of belief in the superiority of a few "great civilisations", we are increasingly realising that there were no true "dark ages", and that civilisation has always progressed. Hell, some of the greatest monumental engineering and architecture came out in the Middle Ages, and they dubbed it "Gothic", suggesting it was barbaric and uncivilised when it was structurally superior to the relatively unsophisticated Classical styl of pillars and basic arches.

Re:Long distance travel

[Sarten-X]

40km is still only about 25 miles, which is well within that single horse's range. Interestingly enough, such a race already exists, and though it is usually won by a horse, humans have won before - and would likely win more often if the horse's maintenance times were counted in addition to the actual travel time.

Spurred on by this discussion*, I looked around a bit more, and I found an interesting article considering how humans can eventually outrun most other animals, complete with references.

* Pun intended. I'm terrible.

Re:Long distance travel

[khallow]

A human can keep up a 3mph walk forever as well.

Not in reality. I notice that typical thru travel times for the Appalachian trail (2100 miles) are between 150 and 210 days which is again close to 10 miles a day.

When I was in college we went on a hike to the bottom of the grand canyon for a week. None of us were in great shape, did any training, or probably near as fit as a peasant who worked all day in the field every day yet we averaged about 20-25 miles a day for a week with heavy packs on rough terrain and making camp each night.

Healthy college students - for only a week. A peasant who works all day in a field is not going to be that fit because they aren't doing that sort of exercise and they just wouldn't be that healthy either due to nutrition, disease, and poorly treated injury.

For endurance running a human is every bit as good as a single horse. The pony express used multiple horses because horses are faster over short distances but over multiple days a human is actually faster. A good runner can do alot more than 35 miles per day.

And a good horse rider with multiple horses can do a lot better than that. For example, Commanche and Mongol riders could easily do 75 to 100 miles a day by this means.

The article on humans outrunning every animal on the planet is in error since horses are faster with similar endurance. They just can't be carrying a heavy rider all the time.

Re:Long distance travel

[Wycliffe]

And a good horse rider with multiple horses can do a lot better than that. For example, Commanche and Mongol riders could easily do 75 to 100 miles a day by this means.

Again, you've changed the criteria to multiple horses. A peasant would be unlikely to have access to a single horse let alone have access to
multiple horses along a route. Most likely during this time though period people would rarely travel further than the closest village and only
traders would travel to the next village probably with a donkey or two. Even today most people rarely travel further than the closest town to
do business except on special occasions.

Re:Long distance travel

[khallow]

Again, you've changed the criteria to multiple horses.

Which is an obvious thing to do since it both was used in history at the time of the Black Death and demonstrates a counterexample to the somewhat off-topic claim I was arguing against.

Re:Long distance travel

[hairyfish]

It's very comparable. A human can keep up a 3mph walk forever as well. A 3mph pace is not hard for a human at all and without a pack 30 miles a day would not be an issue for a human. 35 miles per day, six days a week indefinitely would not be a problem for the average person either.

Define "average person". I walk a lot compared to an average western person. I try to knock over a couple of kilometres a day, which might not sound like much, but compared to your average lazy westerner whose only walking is from the bedroom to the garage, it is above average. I can walk about 5kms at about 5km/h without thinking about it, but more than that and I feel it. And I do this almost every day. If I do a 10km walk I need a rest and don't feel much like repeating it the next day. 35miles (60km) in one day would kill me. I work in a company of 2000 people and looking around I would bet my house that at least half of them couldn't walk 5km a day for one week. 60 km a day would pose a huge problem for most western people.

Re:Long distance travel

[Wycliffe]

Define "average person". I walk a lot compared to an average western person. I try to knock over a couple of kilometres a day, which might not sound like much, but compared to your average lazy westerner whose only walking is from the bedroom to the garage, it is above average.
I can walk about 5kms at about 5km/h without thinking about it, but more than that and I feel it. And I do this almost every day. If I do a 10km walk I need a rest and don't feel much like repeating it the next day. 35miles (60km) in one day would kill me.
I work in a company of 2000 people and looking around I would bet my house that at least half of them couldn't walk 5km a day for one week. 60 km a day would pose a huge problem for most western people.

I would consider myself fairly "average" by your definition. I sit at a desk all day and work from home so I don't even have
to walk to the garage. I could probably afford to lose 15 pounds but I still have no problem on vacation going to the zoo,
six flags, disney world, etc... and walking for 8-10 hours straight at probably around 5km/h with no issues for an entire week.
So I'm guessing that I get close to the 35mi/60km per day where generally on a typical day I'm probably lucky to hit
3000steps/2km in a day. At least for me, walking indefinitely even when I don't do it regularly doesn't seem to be an issue
and would presumably get easier over time.

Re:Long distance travel

[cusco]

a traveller on land who fell sick would be unlikely to continue his journey.

An adult traveler. Children in arms or carried in the cart/wagon/travios by parents fleeing the plague could travel quite a distance. If the parents were royalty or related to the gate guards they could probably the enter and infect the next community, if not they could camp outside the gates and infect the local rat population.

Infected humans are not the only way the disease could travel, either. Fleas can live for months without eating, a single infected flea burrowed into the hem of a traveler's cloak, in a bolt of fabric, or stuck in the oil of a boot seam could go a very long way before jumping off and dining on a passing rat. There are many occurrences of plague arriving in a town or monastery where no infected persons had been admitted and even where no traveler had visited for months prior.

Re:Long distance travel

[s0nicfreak]

You don't walk for 8 - 10 hours when you go to Six Flags or Disney World; you wait in lines at times, you stop to eat and drink, you stop to talk to whomever is with you about where you're going next. You may be on your feet but you aren't constantly walking, and that's quite a difference. (Ask any cashier that is on their feet 8 hours a day to walk for 8 hours a day instead.) I had no problem walking around "all day" for 3 days at a convention a few weeks ago, but if I am walking from one location to another, I can walk for maybe 40 minutes before getting tired out, and in that time I walk just over a mile. The difference is, when you don't have a destination you're trying to get to, you take a lot of breaks that you don't think about.

Yes, I could build that endurance up, and be able to walk faster and for longer amounts of time (I use to walk 4 miles to work in an hour, then back home again after a day of working, without getting tired out - because I did it every day); but a horse used for traveling is already conditioned to walk for longer and faster than I am, because he does it every day - on days when he isn't used for traveling, someone has him run around in a circle.

Re:Long distance travel

[Capt.Albatross]

a traveller on land who fell sick would be unlikely to continue his journey.

An adult traveler. Children in arms or carried in the cart/wagon/travios by parents fleeing the plague could travel quite a distance.

Good point - I had overlooked that possibility.

Infected humans are not the only way the disease could travel, either.

While I don't disagree with anything you say, I am not sure that animal vectors make a difference to this particular study. The question I have is, did the animals spread the disease across the continent independently, i.e. other than by being transported by humans, to any significant extent? If so, then we can only say that the data give an upper bound on the rate of spread by humans. While this would raise the possibility that this rate was lower than that calculated by the authors, it does not provide any evidence that it was. Conversely, if the spread by animals depended largely on them being transported by humans, their involvement in the process is immaterial to the use of the data in estimating human mobility. This estimation must be based on the average rate, not on relatively infrequent worst-case or corner-case scenarios.

Re:Long distance travel

[Capt.Albatross]

I am being serially dumb here. I see now that the animal vectors allow the disease to spread at the rate of asymptomatic travelers.

Re:Long distance travel

[hairyfish]

So I'm guessing that I get close to the 35mi/60km per day where generally on a typical day.

Guess again. Actually instead of relying on wildly inaccurate guessing I suggest you should maybe go for a 60km walk and get back to me. Trust me, standing around Disneyworld for a day shuffling a few metres here and there while sitting down on rides and eating lunch etc is not even close a 60km straight march.

Re:interesting question

[Jeremiah Cornelius]

Rats. Crusades. Trade.

They had Silk in freaking Budapesht, Kiev, Oslo, Bruges, Orleans, Stuttgart and Florence. How isolated do you think the world was?

This makes a lot of sense..

[Anonymous Coward]

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

[Anonymous Coward]

Boats have been around for thousands of years and move faster than the 2km per day spread the study shows.

Re:boats

[Anonymous Coward]

Is everyone on Slashdot incapable of understanding that in a village of, say, 100 people, you'd have two or three per generation who'd actually be traveling distances for work? And that when they did *they wouldn't be doing it every single day*? The spread of the plague like this is an averaged thing. No-one is pretending that no-one traveled more than 2km a day; that's a very rapidly, demonstrably inaccurate thing to say. You'd be better off using evidence like this to support the idea that *on the whole*, *overall*, *in general* people didn't travel very far, which is no fucking surprise given that they had to work seven days a week on their fucking fields to support some inbred cunt of a feudal lord.

Not news

[DerekLyons]

From TFS:

In other words, people in medieval society were linked almost exclusively to others nearby and so did not form a small world network.

Um, who exactly is this news to? Historians and sociologists have known this for decades.

Or sick people didn't travel

[nullchar]

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.

Re:Or sick people didn't travel

[painandgreed]

Or sick people didn't travel.

True, but they could with steam ship or train. This effect was seen in WW1 and was in an article about the great flu epidemic and why it was so great. Usually, sick stay home and don't travel while well people do. In the war, the really sick were evacuated out of the trenches and back to cities and sometimes back home, while everybody else stayed.

Re:Or sick people didn't travel

[nullchar]

Exactly. It's quite difficult to walk or ride a horse while very ill. But lying on the floor on a steam ship or train car will spread the illness around.

This rumor I heard

[jovius]

So it's true that I could catch some disease if I go out then?

Madagascar?

[Anonymous Coward]

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.

Vectors

[Richy_T]

What if human beings were not, in some way, a vector?

Also, the property of rain is to wet.

[starX]

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.

Re:Also, the property of rain is to wet.

[MozeeToby]

What they are talking about is the same phenomenon in medieval terms; they're arguing that even by our current understanding they had limited contact with the wider world. Look at it this way, at an average spread of 2km per day and an incubation period of days or weeks, all it would is a single traveler to blow that average out of the water. One guy riding a horse for 2 hours a day could plant incubation sites 50 or 100 km ahead of the larger wave of the outbreak before he even knew he was sick. So, either there were practically zero long distance travelers (an idea which I find hard to believe) or long distance travel all but stopped after the outbreak started.

Re:Also, the property of rain is to wet.

[radarskiy]

"Duh: The Journal of the Insipidly Obvious"

Obviousness is not much of a basis for a scientific theory.

"communication and travels was much slower in the middle ages"

Not the question under study.

"not even like we're talking about a time when humanity was on the cusp of "small world" connectiveness."

Fact not in evidence.

Re:Also, the property of rain is to wet.

[starX]

Why would you find minimal long distance travel hard to believe? Also, since in the years following the black death, in England at least, laws were passed to tie workers to the land and punish masterless men and vagabonds: there were so few peasants to work the land that the lowest classes could demand higher wages and buy their way into the yeoman class, but the anti-vagabond laws were designed to put an end to that. This is well documented, but even before then few people would have left the immediate vicinity of their farms if they had any say about it.

Double edged sword

[DidgetMaster]

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.

Re:interesting question

[bhagwad]

It's ridiculous that you need researchers to tell you that spreading disease became more easy with rail technology or with long distance shipping. I mean, what have they revealed that we didn't already know?

Re:interesting question

[drakaan]

I think the not-so-amazing revelation is that people in the 14th century were generally travelling very small distances on a daily basis. The world wasn't isolated in terms of accessibility, but in terms of time-to-destination. That's my understanding of the summary, at least.

Look at tourism

[Aviation Pete]

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/)

Re:interesting question

[tepples]

How fast do you think this silk moved across Europe?

Re:interesting question

[Jeremiah Cornelius]

Just because the mean was so bad, doesn't mean that there weren't significant outliers, with difference on orders of magnitude.

Agree, about the revelation. Then? There are folks in rural Wisconsin who've never been to Milwaukee, Des Moines or Chicago.

American Natives could have told you that

[themushroom]

...or the ones that survived the smallpox.

Is that the lineup of a Death Metal concert?

[Optali]

\m/
Srry mates, it's friday...

Re:Is that the lineup of a Death Metal concert?

[Sir_Eptishous]

The first all-African-American heavy metal band.

Re:Is that the lineup of a Death Metal concert?

[hondo77]

Only because people didn't know about the existence these guys yet.

Re:Is that the lineup of a Death Metal concert?

[Optali]

http://www.youtube.com/watch?v=OwehxN2ipCU

Re:interesting question

[Optali]

good point.

And we have to recall that Europe was jsut a very small part in the backwaters of a huge world connected mostly by sea with the Arab traders on one side, Asia and China on the other (until China closed itself later) and of course, the Mongols.

my hometown

[JustNiz]

My hometown (Weymouth, Dorset) has the dubious distinction of being the port where the black death entered England. Cool huh?

Re:interesting question

[wanax]

The wide distribution of silk merely implies that there was some trade -- it doesn't imply at all that the markets weren't so thin that a single caravan's choice of whether to travel or not didn't control the availability of new silk for year(s) at a time. Try reading Hakluyt's voyages some time -- organizing even a single successful long distance trading caravan was not an easy operation.

I think one thing that people often forget about the great steam age of transportation, is that the flows of people were bilateral, and mostly symmetric. While some residual of the passengers who left Europe for, say, the US stayed, mostly they eventually came back to were the left from -- those steam ships leaving from New York were crowded. Comparing that to the Crusades is apples to oranges: Sure, quite a few people left France and the HRE for the middle-east, but nearly all of them stayed once they arrived. Only a very few top-tier nobility and traders ever intended to return to their homes.

The difference between 'large' and 'small' world networks here is that for a small world, we can make the statistical assumption that there will be interpersonal contact between people all over the world at a fairly small tau (say, 4 days). What this research shows is that assumption isn't met by medieval European society at the time of the Black death. Quite likely, because long-distance travel and trade were sufficiently small scale that a few individuals' decisions (say, on hearing about the plague) could radically change the structural dynamics of the network for substantial periods of time.

Re:interesting question

[ShanghaiBill]

what have they revealed that we didn't already know?

They have revealed that high speed long distance travel was not common before it was possible. Who would have guessed?

Re:interesting question

[Optali]

Well, rather fast.
We had a network of roads, the Hanseatic societies and most importantly rivers and the sea.
It took a ship a few weeks to get from here in Amsterdam to anywhere in the Baltic, and the same counts for the Mediterranean. Recall that the Italians and Catalonian had huge fleets?

And BTW, 2km is crap, in these times you would have travelled much more just from one village to another. These 2km per day make no sense at all.
OK, it's maybe the mean or the average but it still makes no sense. OK, people in villages may have stayed close to home... but our smart "scientists" just forgot that in these days people had a favourite hobby that consisted in gather in huge numbers dressed in fancy metallic suites and go paying their neighbours a visit... they called in "armies" you know?

And there were fairs, and the aforementioned merchants, and comedians and pilgrims.... and this was just our dear old Europe, a little place in the backwaters of the medieval world filled with simple barbarians.

Re:interesting question

[disposable60]

There are a fair number folks in Brooklyn who are born, mature, marry, reproduce and die without going outside a 25-mile radius. The percentage of peripatetics is much larger now, but the sticks-in-the-mud are still multitudes even in industrialized countries.

Re:interesting question

[Jeremiah Cornelius]

The "Arab" traders were really a remarkable multi-ethnic amalgamation of Levantine and peninsular Arabs, Africans from the horn, Persians from the gulf, and Indians from the Arabian sea - Malabar Coast and Gujurat. There were also Genoans, Turks and Georgians from the Caucasus - with plenty of overlap by Chinese through the time of Kublai, under the Mongols.

This was the world of Sinbad, and the true inheritor of the great maritime civilizations in the Mediterranean - Tyre, Mycenae and Athens.

Re:interesting question

[K. S. Kyosuke]

How fast do you think this silk moved across Europe?

I'm not sure but I've heard they already used bitcoins back then to pay for it.

Black death resided in fleas on rats

[kawabago]

Ships spread infested rats from port to port. So it was a small world network in the technology of the day.

Huh

[koan]

Did they factor in other vectors? Birds, weather, insects etc.

Interesting

[koan]

I wonder how today's societies would react to the modern day equivalent of one of these plagues.

Re:interesting question

[roc97007]

Rats. Crusades. Trade.

They had Silk in freaking Budapesht, Kiev, Oslo, Bruges, Orleans, Stuttgart and Florence. How isolated do you think the world was?

I think the point was, it's not the distance, it's the speed and frequency.

The bright side...

[roc97007]

...is that we wouldn't have modern epidemiology and many advances in modern medicine had the issue not been pushed by the "small world" effect.

Re:interesting question

[medv4380]

One year for the silk to travel the silk road. The black death spread rapidly along it as well.

Re:interesting question

[aBaldrich]

>these days people had a favourite hobby that consisted in gather in huge numbers dressed in fancy metallic suites and go paying their neighbours a visit

Yea, and today people have a favourite hobby that consists in building small scale unmanned aircrafts and go bombing their neighbours... oh wait, they don't.

Re:interesting question

[Sir_Eptishous]

Great post.

Re:interesting question

[LordLimecat]

This author is astonishingly ignorant. There was a bigger bubonic plague outbreak in the 7th century in Constantinople. It spread to...

central and south Asia; North Africa and Arabia;[citation needed] and Europe all the way to Denmark and Ireland

(thanks wikipedia), and its suspected to have originated in China or in Egypt (a lot of wheat was imported from there).

This meme that somehow the world wasnt "globalized" until the 19th century is hilarious, and wrong.

Worse Yet

[b4upoo]

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.

Re:Worse Yet

[evilviper]

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.

Air travel only shrinks the oceans... Cars / trains / horses / bicycles are good enough to spread a plague entirely across two or three continents, even if air travel didn't exist at all.

For the sake of destroying the world economy, you'd only be keeping 15% of the world population safe from the plague, and only in the event of a fast-moving infection... Slower-acting infections could be spread via ocean-liner just fine.

Re:interesting question

[Anonymous Coward]

That's what I keep telling my wife.

Re:Holy Carp!

[geminidomino]

Back then, it was called Prodigy.

Re:interesting question

[drakaan]

Well, we're talking about a difference in speed of horse-based travel compared to human walking. There's a difference, but not orders of magnitude. Color me unsurprised about the speed with which the plague spread.

Re:interesting question

[Anonymous Coward]

2KM a day sound legit. In reality, you stayed in town for a week doing merchant things, then went 12KM to the next town where you would spend the next week.

horses weren't common and stopped the spread

[dutchwhizzman]

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.

Re:horses weren't common and stopped the spread

[yet another SanTiago]

> The spread of the virus might have actually occurred

Well, it is generally accepted that the Black death was caused by bacteria (Yersinia pestis), not virus.

Re:interesting question

[Isaac-1]

I think what we tend to forget is how much of a chore that travel was to people that were walking or traveling by wagon. My paternal grandmother grew up in a what was one of the last frontier areas in the central part of the United States, in the late 1890's the 50 mile wide strip of land in western Louisiana that was disputed territory with Spain prior to the Texas Independence in the 1830's , and remained virtually uninhabited until timber rush of the 1880's. The nearest city of any size was the river / ocean port city of Lake Charles 50 miles away by road or 75 miles indirectly by rail 10 miles away (post 1905). During this time the town she lived in was a booming timber mill town with a couple of thousand people, her father owned one of the two general stores in the town, and would travel to Lake Charles once every 4-6 weeks for supplies., this was usually done by wagon, taking 2 or 3 wagons which his children would help drive. This was a 2 day trip, the first day was spent traveling with the empty wagons to a point where there was a ferry that crossed into Lake Charles on the west bank of the Calcasieu river near the present day town of Moss Bluff, where they would camp out over night in the wagons. Early the following morning her father would take the wagons into to Lake Charles (which had a population of 7,000- 12,000 people at this time) to buy goods, leaving the kids at camp to fix food for the day's travel, and prepare the wagons., they would then set off traveling home with their loaded wagons by mid morning, arriving back home late in the evening. Needless to say such long distance travels were not common for many of the children of the community, and likely few of the adults as well, and this was around the turn of the 20's century, well into the age of steam engines, and around the birth of the automobile..

Re:interesting question

[Jeremiah Cornelius]

Thanks. This whole "clash-of-civilizations" bullshit always pisses me off! It's ahistorical and anachronistic. Maritime Islamic regions arguably had a better understanding and application of Classical Athens and Ionian culture and achievement than "Western" leaders do, today...

Re:interesting question

[I'm New Around Here]

Then again, those armies were generally not in the habit of hugging or kissing those neighbours, slowing down the rate of spread of disease as well.

Well, they may not have hugged and kissed the men, but the winning side didn't mind hugging and kissing the remaining women.

Re:interesting question

[I'm New Around Here]

It's what I keep telling you wife too. I'm only in town every other Tuesday.

Re:interesting question

[Jeremiah Cornelius]

But I a sure it serves somebody's agenda...

This belongs to the "Malcolm Gladwell and Thomas Friedman school" of Deep Thinkers (TM).

Re:interesting question

[cusco]

My uncle knows a 40-some year-old woman who has never been off the island of Manhattan, and can't imagine any reason for doing so. I'm utterly unable to understand such a viewpoint.

It wasn't long ago when most people, even those who were lucky enough to own a horse, never strayed more than 20 miles (generally a day's journey) from home. In many cultures travelers were welcomed with open arms, as they were the only source of news of the outside (aside from invading armies).

Re:interesting question

[AnotherAnonymousUser]

Have you got any good readings you can recommend on the subject =)?

Re:interesting question

[Anonymous Coward]

I'd love to agree with you, but I can't.

"We had a network of roads" along which you couldn't move faster than you, or your horse, could walk.

"the Hanseatic societies" who had internal combustion engines back in 1640?

"and most importantly rivers and the sea" because everyone who's ever got into a boat knows that you move at ten times the speed of a walker, no matter what

"It took a ship a few weeks to get from here in Amsterdam to anywhere in the Baltic, and the same counts for the Mediterranean"

this doesn't even make sense. did it take a few weeks to go from amsterdam to the mediterranean, or from the mediterreanean to the baltic? and if it took "a few weeks" to get from amsterdam to the mediterranean -- a trip taking one through the english channel and down the coast of france, which is an extremely bad-weathered trip particularly around the bay of biscay -- how the *sweet fuck* does it take the *same amount of time* to get to the baltic? i don't think you know what you're talking about. no, scratch that. you don't know what you're talking about.

"And BTW, 2km is crap, in these times you would have travelled much more just from one village to another" because everyone in europe was happily running from village to village every single day.

"OK, it's maybe the mean or the average" but i'm going to ignore that.

"but our smart "scientists" just forgot that in these days people had a favourite hobby that consisted in gather in huge numbers dressed in fancy metallic suites and go paying their neighbours a visit... they called in "armies" you know?"

oh. my. god. you are a moron. do you think that everyone in a village had a "favourite hobby" that "consisted" "in" wearing something that would cost the equivalent of more than ten years' salary and heading off to be killed? do you think that europe was a mess of yearly - or even monthly - battles between heavily-armoured peasants and other heavily-armoured peasants? and that these "armies", which apparently moved around on such a high level as to raise the average distance traveled by common people from a few kilometres a day to, i don't know what you're suggesting so let's ballpark 20km a day, moved every year? fucking hell. seriously. fucking. hell.

you are a fucking idiot.

"And there were fairs," which happened daily.

"and the aforementioned merchants", who each practised the slightly dubious business plan of trumpeting their own wares in every village, and who made up a sufficiently large proportion of the population to push the average daily travel through the roff

"and comedians" taking part in that most famous of mediaeval activities, the stand-up tour

"and pilgrims" who spent every day, in vast numbers, walking kilometre after kilometre, regardless of season

"and this was just our dear old Europe, a little place in the backwaters of the medieval world filled with simple barbarians" which happens to be that europe considered in the article, that europe which was devestated by the black death, which no-one in the article tried to pretend was filled with "simple barbarians".

my advice to you is to fucking grow up. get some history books - get a lot of history books - and skip the "history documentaries" you pretend to watch on tv because they're clearly polluting your brain. people ever since the neolithic times have had trade links that spread across a truly astonishing distance. that does not mean that every person walked the silk route between china and ireland, because that would be a monumentally fucking stupid claim, although it is one you have effectively made. armies in dark age - let alone high mediaeval - europe traversed vast distances at high speed. that does not mean that everyone in eleventh century britain was happily galloping hundreds of kilometres to beat someone up, because that would be a monumentally fucking stupid claim, although it is one you have effectively made. it is also well worth pointing out that virtually no-one in eleventh century britain, w

Re:interesting question

[TapeCutter]

Not sure when it changed and it probably changed in different places at different times. The ordinary peasant didn't go anywhere, Noblemen and Lords owned all land, they did not like their peasant wandering from one village to the next and they certainly didn't like peasants hunting game on "crown land". Today crown land is public land, back then it belonged to the crown and they were not willing to share with anyone, particularly a lowly peasant. Peasants worked/mined the land, they were allowed to keep just enough for themselves to keep them alive.

The effects of this are still with us, there are hundreds of different accents across the UK, there at least half a dozen in Yorkshire alone. That only happens when groups don't talk to each other regularly. This doesn't mean everyone was isolated, wealthy merchants, priests, and the upper class were free to come and go as they pleased. These were the people in society who owned the land and everything on it, including the peasants.

I think the end of that way of life came with the cotton mills in Manchester and surrounds. People started flocking to cities for jobs in the mills, much the same way as modern day Chinese have flocked to the new industrial cities over the last 40yrs. the crossroads of England, Ireland and Scotland is where the original Luddite movement was formed and it's no coincidence that's also where the industrial revolution started, Luddites were basically rich folk, they weren't religious nutters fighting progress they were fighting other rich folk who's factories were "stealing" their peasant workers.

Re:interesting question

[TapeCutter]

It spread an average of 2km day, people can and do walk faster and further than that on a daily basis, it wasn't just the speed difference between human legs and Toyota wheels, it was simply that most people did not travel, period. Travelling anywhere your face was unknown was exceedingly dangerous and the king's men who patrolled the roads and woods normally frowned upon peasants wandering around the countryside by themselves, if you were in the woods for no good reason then you were a poacher, if you were out on the road for no good reason you were either a highwayman or an unwelcome Gypsy (Queen Elizabeth's the 1st name for Egyptians). Most people were farmers or servants of one kind or another, they worked their arse off for the landlord for the privilege of living on the lord's land and using the lord's market place/village. In short systematic economic slavery across all of Europe was the norm before the industrial revolution, Victorian era factories full of kids may look unbelievably inhumane to modern eyes but they were a godsend to the majority of peasants who were living and working in even harsher conditions.

Paced by the Animals

[TheRealHocusLocus]

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

The catalyst for increased mobility was...

[Anonymous Coward]

...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.

Re:interesting question

[gl4ss]

there were villages more evenly spread back then. the whole population was spread more evenly.

and the middle ages are middle ages because they are the dark middle ages... fucking kings had troubles even getting their taxes. Hansa stayed mostly on the coasts, because trade monopoly on the seas was their thing. even that was slow. and port cities had quarantines for incoming ships during the worst plague times.

there were seafaring exceptions of course but getting stuff from the orient was a monumental job in those days. a year to there a year to back if you were in luck.

the 2km is just an average. of course when it spread to a city it spread through there quite fast.. but geez, travelling around wasn't that simple back then and it sure got a lot faster with railroads and better roads.

as for war.. well.. yeah they did go on campaigns. not every year of course since campaigns might take a fucking decade(or 3) to execute and get the soldiers back if they did come back. again the armies moving quite slowly. railroads later being constructed in several countries mainly from army pressure.

a major point with plague though really being that you'd be dead before managing to walk too far :). this really slows down the spread in a world where it takes days to get anywhere.

Re:interesting question

[Half-pint HAL]

Actually, it's not the horses that made the difference, it's the boats. The most obvious difference between a boat and a plane is speed, and it's one of the side-effects of that speed that matters here: if you got on a long-distance sailship incubating a disease, you'd be showing symptoms before you reached your destination, and the ship would be quarantined at anchor in the harbour until everyone on board is either dead or symptom-free. With planes, you'll feel a bit off and you'll be infecting other passengers, and you'll be off the plane and out of the airport long before you realise just how ill you really are.

Re:interesting question

[Optali]

"More evenly spread"? Have you ever been in Europe, mate?
And nope, the Dark Ages are one part of the middle ages, exactly the time from the fall of the Roman Empire up to the year 1000. The period of the Black Plague is 1348 - 1350, the last period of the Middle Ages shortly before the Renaissance (which started after the Black Plague).

I guess you know there's a place in Europe called "Italy", well it happens that one of the principal routes of the Hansa was from the Nothern Hanseatic capitals to Venice and Genua... unfortunately during this period travelling by plane was a bit difficult so that they had no other choice than doing ig by horse.

Yes, a WAR took decades... but sending a nice horde of horsemen to utterly annihilate whole countries didn't take much more than a few years... Recall Genghis Khan? And our good old continent is rather small: You can cross it in a few weeks afoot.

And you happily forgot that it wasn't only the Hansa and the armies who where travelling our map from corner to corner: Shepherds travelled a lot of miles, and they still do nowadays for instance in Spain were they keep the Merino herds in the north during the winter and travel hundreds of kilometres by foot in the winter.
And of course, the peasants had to sell their stuff, and there a lot of tradespeople constantly on the road, gipsies, comedians, travelling monks, apprentices and pilgrims, mostly to Rome and to Compostela. And this is not something you read in history books, some of these traditions are still kept like the Pilgrimage to Santiago or the German Wanderschaft.

The very cities of central Europe were born out of this traffic: The two towns where I passed my childhood, Hildesheim and Hannover were born this way: On a river crossing on one of the mayor routes where people stopped to rest during after crossing the river or before doing it, a market was born and around the market a city. This was around the years 1000 to 1100,

And how to you think the cathedrals, churches, castles and mayor building were built? Local population? You played too much Ebony mate. it took years to become a master stonemason able to do the type of quality work needed for a cathedral or a castle.

And in any case: What is the point of this whole study anyway? Saying that the plague spread slowly? A plague that killed between 75-200 millions in 2 years?
A plague that in in India in the modern times (until the 1980s actually) with all the communication networks in place and a population density higher than in any previous period has only been able to infect a few hundreds of persons? So what is the point then? Shouldn't they be studying why it spread so FAST and not trying to prove that there was no possible way for it to spread?

If you get a plague and die before you can walk to the next town... well, how does the next town get infected hen? By homoeopathic transmission through water? Via infected email? Yes, there were rats, but it's these who don't travel too far eve when infected.

So, the big question here is: WTF is this study about?

Re:interesting question

[Jeremiah Cornelius]

Have you got any good readings you can recommend on the subject =)?

Registration and Purchase required? PDFs from the New Cambridge History of Islam. There's an amazing maritime section here:
http://universitypublishingonline.org/cambridge/histories/ebook.jsf?bid=CBO9781139056137

Blow your mind, with the journal of the travels of 14th Century adventurer, Ibn Batutta. He makes Marco Polo look like a homebody.
https://en.wikipedia.org/wiki/Ibn_Battuta

1929 abridged translation of Ibn Batutta's journals:
http://books.google.co.uk/books?id=zKqn_CWTxYEC

More books? Warwick Ball is an accessible archaeologist and historian, who effectively destroys the case for "Clash of Civilizations", and the entire dubious taxonomy of "east and west".
http://www.amazon.com/Rome-East-Transformation-Warwick-Ball/dp/0415243572/ref=sr_1_1?s=books&ie=UTF8&qid=1382201303&sr=1-1
http://www.amazon.com/Out-Arabia-Phoenicians-Discovery-Europe/dp/1566568013/ref=sr_1_5?s=books&ie=UTF8&qid=1382201303&sr=1-5
http://www.amazon.com/Towards-One-World-Ancient-Persia/dp/1566568226/ref=sr_1_3?s=books&ie=UTF8&qid=1382201303&sr=1-3

Nice, "pro-Nabatean" writeup on the late-antique origin of Arab maritime trade, after the breakup of Alexandrian east. You will have to go farther back, to the Phoenicians of Tyre and Carthage, 'tho! This author begins with Nabatean emergence. There are many links on this site... Quite fascinating.
http://nabataea.net/who1.html

Oman and maritime history. Nice to overlay this with the Nabateans. These things met and mingled - especially out in the Indian ocean, away from home:
http://www.maritime.om/Oman-Maritime-History

The sections on Ancient Indian and Chinese maritime development is slim, but worthwhile:
https://en.wikipedia.org/wiki/Ancient_maritime_history#Indian_subcontinent

An Indo-centric, but factual and entertaining page:
http://www.aseanindia.com/navy/maritime-history

Summary of "silk-routes":
http://www.silkroutes.net/SilkSpiceIncenseRoutes.htm

Genoa in the Crimea:
https://en.wikipedia.org/wiki/Genoese_colonies

Technology of early Islamic ship-building - mostly focused on Mediterranean, not Indo-Persian
http://www.academia.edu/1596791/Early_Islamic_Maritime_Technology

Re:interesting question

[drakaan]

Same argument as the one I was making...boats, horses, and walking are all slow. Cars, trains, and airplanes are fast. We are in agreement.

Re:interesting question

[uninformedLuddite]

I would have thought it bugs the question

Re:interesting question

[Reziac]

There probably were a lot more of these travellers than we know of... anyone who didn't keep a journal, or show up in someone else's preserved writings, is lost to history.

Re:interesting question

[RockDoctor]

There was a bigger bubonic plague outbreak in the 7th century in Constantinople.

The Justinian Plague was a big one, no doubt about that. What it's causative organism was is rather less clear. Bubonic Plague has certainly been put in the frame, but I don't think that the case has been closed.

Oh, sorry, I see that the case has been pretty much nailed shut in the last few years. I withdraw my objection.

^ Wiechmann I, Grupe G. Detection of Yersinia pestis DNA in two early medieval skeletal finds from Aschheim (Upper Bavaria, 6th century A.D.).Am J Phys Anthropol. 2005 Jan;126(1):48-55

^Harbeck, Michaela; Seifert, Lisa; HÃnsch, Stephanie; Wagner, David M.; Birdsell, Dawn; Parise, Katy L.; Wiechmann, Ingrid; Grupe, Gisela; Thomas, Astrid; Keim, P; ZÃller, L; Bramanti, B; Riehm, JM; Scholz, HC (2013). "Yersinia pestis DNA from Skeletal Remains from the 6th Century AD Reveals Insights into Justinianic Plague". In Besansky, Nora J. PLoS Pathogens 9 (5): e1003349. doi:10.1371/journal.ppat.1003349. PMC 3642051. PMID 23658525.

In a way, that's a relief ; if we know what caused that plague, then that's one fewer nasty pathogen to worry about.

Re:interesting question

[Jeremiah Cornelius]

There probably were a lot more of these travellers than we know of... anyone who didn't keep a journal, or show up in someone else's preserved writings, is lost to history.

I'm sure that these were often lost in the destruction of Baghdad, and other catastrophes to the world's written record. Also, the labouring seamen - who were mostly unlettered. But of accounts, there are still many such, from the Muslim world, between the rise of the Ummayids, and the destruction of that world by the Mongols and the plague.

There was a very high level of literacy in Islam, which had leveled most aristocratic social structures and replaced those with scholastic meritocracy - in general, if not universally. The tales of pilgrimages - especially by Sufi travelers to memorials of saints, etc. - are numerous, and show a diversity that spans individuals from Morocco or Spain, to those in India and areas that are now former Soviet republics, or Western states in today's China. These travelogues are often interspersed with spiritual discourse, lectures on etiquette and chivalry, or histories of Saints.

'Ibn Batutta is still a real prodigy in this company. His travels are unrivaled by those of B'ahauddin Nakhshband or Shah Nimatullah Vali, mostly a centruy later, or of 'Ibn 'Arabi, a century before. He also is one who produces a monograph focused on the travel as central to a history and documentary - instead of a peripheral circumstance, in a treatise on other topics.

Re:interesting question

[Half-pint HAL]

But it's not simply speed, that's my point. You don't get the quarantine issue with land-based travel, which was slower than sea-based travel. It's the boat as a closed environment that makes most of the difference. You could probably get from Alicante in Spain to the toe of Italy quicker by boat than by bus, and a plague bus would be unwittingly spreading its disease at various motorway service stations on the way, whereas the plague boat would be isolated, and the symptoms would hopefully start to show before reaching the destination, thus giving the chance for total quarantine.