American Indians were very, very roughly speaking the equal of Old World farmers of crops. But American Indians were inferior to the Old World raisers of animals. The horse, cattle, sheep and goat are all of Old World origin. The only American domesticated animals of any kind were the alpaca and the llama.
One of the early advantages of the Spanish over the Mexican Aztecs, for instance, was that the Spanish had the horse. It took the American Indians a little while to adopt the horse and become equals on the field of battle.
You talk about the horse being an advantage in war. What other impacts did the adoption of domesticated horses have on the Americas?
Horses not only helped in war but in peace. The invaders had more pulling power—not only horses but also oxen and donkeys. When you consider the great buildings of the Old World, starting with the Egyptians and running up through the ages, people in almost all cases had access to thousands of very strong animals to help them. If you needed to move a ton of whatever in the Old World, you got yourself an animal to help you. When you turn to the Americas and look at temples, you realize people built these. If you need to move a ton in the New World, you just got a bunch of friends and told everybody to pull at the same time.
What diseases are included in the Columbian Exchange?
The Old World invaders came in with a raft of infectious diseases. Not that the New World didn’t have any at all, but it did not have the numbers that were brought in from the Old World. Smallpox was a standard infection in Europe and most of the Old World in 1491. It took hold in areas of the New World in the early part of the next century and killed a lot of American Indians, starting with the Aztecs and the people of Mexico and Peru. One wonders how a few hundred Spaniards managed to conquer these giant Indian empires. You go back and read the records and you discover that the army and, just generally speaking, the people of the Indian empires were just decimated by such diseases as smallpox, malaria, all kinds of infectious diseases.