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How Did the World Become Interconnected?
How Did the World Become Interconnected?
New trade networks caused an explosion in the trade of goods, but also in ideas, technologies, and diseases.
As this video progresses, key ideas will be introduced to invoke discussion.
Think about the following questions as you watch the video
What innovations in communication helped speed up the process of interconnection?
What innovations in transportation helped speed up the process of interconnection?
What long-distance trade networks were created by the linking of local and regional exchange networks long before 1400?
What were some of the ideas, technologies, and diseases that were spread on these networks?
What were the four world zones in 1400?
What are Malthusian cycles, and why were they a characteristic of so much of the Agrarian era?
: DAVID CHRISTIAN: In the Paleolithic era,
: exchange networks were tiny,
: linking hundreds or at most thousands of people,
: most of whom lived pretty similar lifeways.
: In the agrarian era, they got much larger
: as populations grew and as the number
: of settlements expanded.
: They also got much more diverse as people began to specialize
: so they could bring different types of information
: to the exchange networks.
: And all of this speeded up processes
: of collective learning.
: It's not that people got smarter;
: it's just that there were more of them,
: there was more information, and over time they got better
: at sharing their information.
: Technologies of communication and transportation,
: once they improved, also sped up these processes.
: They magnified the size, the diversity,
: and the efficiency of networks of exchange.
: Improvements in technologies of communication
: did a lot to enhance the power of networks
: of information exchange.
: The invention of writing 5,000 years ago
: was particularly important because what writing did
: was to lock in information over many generations.
: Writing explains why we can still read the laws
: that Hammurabi issued in Babylon 4,000 years ago
: because he carved them in blocks of stone.
: More recently, the invention of paper and printing
: has revolutionized the storage
: and dissemination of information.
: In fact, here I am in Cheongju in South Korea,
: where the first book was printed using moveable metal type.
: It was actually printed in 1377,
: which is 78 years before Gutenberg
: built his press in Europe.
: Improved technologies of transportation
: also made a huge difference.
: The use of horses, of oxen, and camel to transport
: people and goods revolutionized both transportation and warfare.
: They also allowed pastoral nomads
: to settle the steppes of Eurasia,
: creating a huge mobile zone that ran all the way
: from East Asia to the Mediterranean
: and allowed a huge movement of people, of ideas, and of goods.
: Meanwhile, in Southeast Asia, new boat-building technologies
: and new navigational techniques allowed people to start
: migrating into the Pacific Ocean until, by 1,500 years ago,
: they had settled most of the islands of the Pacific.
: And finally, the great empires of Persia and China
: started developing road systems and courier systems,
: and those systems provided the most efficient ways
: of moving information until modern times.
: In Africa and Eurasia, long-distance
: trading systems developed.
: And what they did was they connected
: exchange networks.
: The first of these carried goods, people,
: and ideas by sea from China around India to Africa
: and the Mediterranean and backwards.
: The second is known as the Silk Roads.
: It carried goods, people, and ideas by land,
: connecting China, Central Asia, India,
: and the Mediterranean world.
: As a result of these networks, 2,000 years ago,
: silk was being traded all the way from China
: through Central Asia to Rome and Egypt.
: At the same time you could find Roman coins
: all the way from Britain to Vietnam.
: A thousand years ago, wealthy Persian consumers
: could order specially designed porcelains in China
: and have them transported
: specially around India to Persia.
: In the 1400s, a Chinese imperial fleet
: went to Africa, picked up a giraffe,
: took it back to Beijing, and presented it
: as a gift to the emperor.
: And in the same century, a Muslim traveler, Ibn Battuta,
: traveled all the way from Morocco, to Central Asia,
: to India, maybe on to China, and wherever he went,
: he encountered Muslims.
: As Ibn Battuta's experiences show,
: religions also traveled along these exchange networks.
: Buddhism, for example, traveled from India
: through Central Asia to China, Korea, and Japan.
: While Islam traveled from Arabia to Persia, to Central Asia,
: to India, and Southeast Asia.
: Technologies also traveled these routes.
: For example, East Asian techniques
: of printing, of gunpowder manufacture,
: and also of paper-making traveled through central Asia
: to the Mediterranean and to Europe.
: But diseases also traveled these routes,
: devastating diseases.
: We know that 1,800 years ago there were smallpox epidemics
: in Rome, and almost certainly, these were transmitted
: through the Silk Roads.
: But worst of all, of course, was the Black Death
: in the 1400s.
: These seems to have traveled from China,
: through central Asia, to the Mediterranean
: and Europe, and wherever it arrived,
: it decimated populations in the great hub regions
: of Eurasia.
: But over time, what these disease exchanges
: also did was to strengthen immune systems
: just as exchanges of ideas strengthened the technologies
: of the hub regions of Eurasia.
: But throughout the agrarian era, there was a clear limit
: to the size, the extent, and the power
: of these exchange networks.
: That's because the world was, in effect,
: divided into four great world zones,
: between which there was hardly any connection.
: It's almost as if human history had taken place
: on four separate planets.
: By far the largest and the oldest of these
: world zones was the Afro-Eurasian zone.
: This extended all the way from Eastern Siberia
: to Southern Africa.
: Within this zone, from as early as
: 4,000 years ago, technologies such as
: the domestication of animals and the use of metals
: diffused over wide areas.
: These technologies had their greatest impact
: in the hub zones.
: Those were the zones
: where there were large populations
: and very diverse connections.
: In the Afro-Eurasian world zone, the major hub zones
: were the Mediterranean and Europe,
: Mesopotamia and the Muslim world,
: Northern India, and Eastern Asia.
: The second largest of the world zones
: was the American zone.
: This was settled from about 15,000 years ago,
: but within it there emerged
: two major hub zones with agriculture
: and agrarian civilizations in Mesoamerica
: and in the Andes region.
: These, however, had smaller populations
: and much smaller and less powerful networks
: than in Afro-Eurasia.
: So fewer ideas were exchanged, fewer people,
: fewer technologies.
: The third great world zone was the Australasian zone.
: Here, until very recently, most people--
: the vast majority of people-- lived as foragers,
: except in the highlands of Papua New Guinea,
: where there were farming communities.
: Now, this meant that populations were tiny
: by Afro-Eurasian standards.
: Exchange networks carried limited amounts of information.
: But nevertheless, in some areas, innovations accrued,
: populations began to grow, and it's possible
: that some societies in this zone were heading, like the Natufians
: 10,000 years earlier, toward some form of agriculture.
: The final world zone was the Pacific.
: This was settled by mariners from Southeast Asia
: from about 3,500 years ago to form what was,
: at least geographically speaking,
: by far the largest of the world zones,
: and by far the largest exchange network.
: Some of the islands, such as Tonga and Hawaii,
: were quite large and they had
: quite large societies and chieftains,
: but on the whole, the distances between islands
: were so vast, populations were so small,
: that the exchanges of information and goods
: and technologies were very, very limited--
: much, much more limited than in the Afro-Eurasian world zone.
: Exchange networks seem to have worked
: most efficiently where populations were densest,
: most diverse, and most interconnected,
: and that meant, of course, above all
: in the great hub regions of the Afro-Eurasian world zone.
: But even here, throughout the agrarian era,
: innovation and growth faced significant limits.
: The most critical of those limits
: seems to be associated with a characteristic pattern
: of rise and fall of populations that you see
: in all agrarian civilizations.
: Here's how it seems to have worked.
: You get an innovation-- say, irrigation.
: It allows populations to rise and they may rise
: for several centuries, but then,
: as the great 19th-century scholar Robert Malthus
: pointed out, there comes a point
: where populations are rising too fast.
: They're rising faster than innovation
: and, at that point, you have too many people to feed.
: Starvation begins to appear. Famines become more regular.
: Diseases begin to spread.
: Governments begin to fight
: over dwindling resources, and eventually you face
: catastrophic calamities like the Black Death in the 1400s.
: If you look at graphs of population growth
: in agrarian civilization,
: you can see this characteristic pattern of rise and falls
: that we call Malthusian Cycles.
: You can see it over and over again.
: Then, quite suddenly in recent centuries,
: the pattern seems to vanish.
: And the reason seems to be that rates of innovation
: increased so fast that they began to overtake
: rates of population growth.
: So here's the question: why did this happen?
: Why did collective learning become so powerful