01/13/08

How Technology Spreads from Point A to Point B
By J. Dalton
One of the main themes of history is technological development. Human beings once lived in small bands of hunter-gatherers using stone tools to eke a living out of the landscape. Now 99% of the world's population stays in one place and eats food that originated on a farm, possibly by way of an electric refrigerator, a supermarket, and a global transportation network. Even those few hunter-gatherer societies that remain tend to use metal tools purchased from their neighbours rather than painstakingly chiseling their kitchen utensils out of stone. But it's not as if every country on Earth invented copper tools, then bronze spears, then iron swords, then transcontinental aircraft. Many inventions were indeed invented multiple times in multiple places. Every coastal-dwelling culture on Earth knows how to make boats and it's unlikely that the Polynesians learned how from the Inuit (or vice versa). Both groups developed ocean-going vessels independent of the other.

Most technologies, however, are acquired from elsewhere rather than independently invented. The nuclear bomb was only invented once and has been copied, given, sold, and espionaged around the world. There are three main ways in which a technology can be transmitted from one place to another- by migration, direct instruction, or copying. Let me use examples from the history of Africa. More than any other continent, Africa has been host to some rather startling discrepancies in technological levels.

First, migration. This is the easiest method for technologies to travel and the easiest to recognize for historians. When a group of people expand and inhabit a new place, they will likely take with them everything they expect to use- including their technology. The medieval inhabitants of Madagascar, for example, knew how to farm and how to make iron weapons because they migrated to that island from Indonesia. When they crossed the Indian ocean they took with them seeds from familiar crops, the knowledge of smelting iron out of iron ore, as well as their language, culture, religion, music, and a host of other traits. Migration also explains how Australians know how to make pianos, how Argentinians know how to raise cattle, and how the French know how to read and write. Piano-makers migrated from Britain to Australia, ranchers from Spain to Argentina, and literati from Rome to France.

Second, direct instruction. This is what happens when one group of people teaches a technology to its neighbours. It may take some time, as the item is first traded and then later built locally, or one group may hire or kidnap an expert from the other side to teach them how to build the item, or may send its own people to the other side to learn the technology and bring it back. This is how the ancient kingdom of Nubia developed its own writing system. Centuries of living upriver from Egypt provided plenty of opportunities for Nubians to trade with, talk to, and occasionally fight with their literate neighbours. Nubian scribes learned how to read and write Egyptian hieroglyphs, and eventually they adapted the technology to their own language (and made it much easier to use in the process- the Nubian alphabet had far fewer letters and took far less time to write). Direct instruction is also how Canada learned how to build nuclear reactors (from the United States), how Islamic nations learned how to build cannons (from the Chinese), and how the Mayans learned how to grow potatoes (from South Americans).

Finally, though this is perhaps the least common method, technology can be transmitted by copying or emulation. Basically, one group of people sees another using a technology that seems very useful, but rather than go over and ask how to do it (and there may be practical reasons not to) some clever individual discovers his or her own unique workaround to invent an identical technology. This is how the Cherokee alphabet was invented. It was also how Germany developed tanks (in an effort to counter the British invention of the same in WWI).

It is still uncertain how ironworking technology traveled from North Africa to Sub-Saharan Africa. We know that North Africans learned how to smelt iron ore from the Middle East where it was first invented (direct instruction). And we know that most of the rest of Africa began using iron tools after the Bantu people migrated out of West Africa into almost the entire southern half of the continent (migration). But the missing link between North Africa and the Bantu is still a mystery.

Perhaps the technology was transmitted through Nubia or Ethiopia, both of which are close enough to the Middle East for direct instruction to occur? This is the most popular theory because it is the simplest. It is significant, however, that Sub-Saharan methods for smelting iron are quite different from those used throughout Europe and Asia. Perhaps this is a case of independent invention? There is no clear historical evidence to say that it isn't. Personally, I like to believe it was a case of copying. With iron in use in North Africa, the Middle East, and in Carthaginian outposts on the coast of the Sahara, it would not be hard to imagine iron tools getting into the hands of West Africans. It is harder to imagine blacksmiths doing the same. With the knowledge that it was possible to make tools out of iron, with West Africans' existing knowledge of copper-working, and examples of the finished product imported along trade routes, all that would be required is one clever West African to invent a way of getting from point A to B, from iron ore to iron knives.

I have no particular historical basis to believe copying is more likely in this instance than independent invention or direct instruction. But it sure makes for a good story.