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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."
So it's true that I could catch some disease if I go out then?
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.
You do not have a moral or legal right to do absolutely anything you want.
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.
"Flyin' in just a sweet place,
Never been known to fail..."
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