The Columbian Exchange

When Christopher Columbus and his men became the first Europeans to arrive in the Americas in 1492, they set in motion a process of cultural, economic, and environmental exchange that had profound effects for the whole world. For the “old,” Afro-Eurasian world, an important transformation included the addition of valuable new food items into the diets of people in such widely separated regions as Ireland, China, and sub-Saharan- Africa.For the”new,”American world, the most significant transformation involved the deadly effects of Afro-Eurasian diseases among its peoples, which in turn helped pave the way for imperial conquest by Europeans. After two centuries of what is now known as the Columbian Exchange, both Old and New Worlds were transformed.

About 12,000 years ago, the land bridge linking the Americas with Afro-Eurasia across the Bering Strait disappeared as a result of rising sea levels. As a result, the peoples of the Americas were almost completely separated from Old World peoples until the Spaniards arrived in 1492. In other words, for twelve millennia the people as well as the plants and animals of the Americas developed in isolation from Afro-Eurasia according to the specific environmental conditions of the Americas.

Some human developments were similar: for example, agriculture and writing developed in the Americas just as they had done in Afro-Eurasia, as did the birth of hierarchical societies and patriarchies (societies headed by the eldest male. In other ways, however, developments in the Americas followed a different course from those of the Old World. For example, plant species such as corn, potatoes, and tobacco were unique to the Americas, and thus American peoples had a different set of choices regarding possible domesticated crops. Just as importantly, not long after humans arrived in the Americas, all of the large mammals that existed there became extinct. As a result, when humans in the Americas began to turn to settled agriculture, they did not have the choice to domesticate large mammals such as cattle or horses. Because of this, American societies did not develop innovations like the wheel, which proved unnecessary without large animals to pull carts or push plows. Furthermore, other animals familiar across much of Afro-Eurasia-including sheep, pigs, chickens, and goats-were nonexistent in the Americas. In fact, the only animals that could be domesticated available to American peoples were the dog, the turkey (in North America), the llama/alpaca and guinea pig(in the Andes region of South America), and the Muscovy duck(in the South American tropics).

The absence of animals that could be domesticated is critical because in the Old World the domestication of animals such as sheep, chickens, goats, and cattle contributed greatly to the development of serious diseases such as influenza, smallpox, measles, and pertussis. In fact, many of these serious diseases resulted from microbes that were first present in herds of domesticated animals and then made the jump from their animal hosts to human hosts. The jump was made much easier because early Afro-Eurasian communities that relied on domesticated animals for food and labor tended to live in close proximity to their herds- even keeping them inside their houses for protection or warmth. Over time, a number of these microbial jumps occurred between domesticated animals and humans. In addition, because of the land connections across much of Afro-Eurasian , these diseases were able to spread to many Old World populations While these diseases continued to be serious for the peoples of Afro-Eurasia, the human populations that survived them over the generations tended to pass on an acquired partial immunity to their offspring.

Without many animals that could be domesticated and living in enforced separation from Old World peoples, the people of the Americas remained freer from the type of contagious diseases that so often plagued the Old World. Some contagious diseases did exist, to be sure, and included dysentery, pneumonia, and possibly syphilis. But the“crowd”diseases of the Old World that flourished in crowds of large, centralized populations of humans did not exist, which meant that American peoples—when exposed to them—had no immunity whatsoever. Therefore, when Europeans carrying these diseases inadvertently spread them among American peoples, sickness spread rapidly, resulting in many deaths.?

1.When Christopher Columbus and his men became the first Europeans to arrive in the Americas in 1492, they set in motion a process of cultural, economic, and environmental exchange that had profound effects for the whole world. For the “old,” Afro-Eurasian world, an important transformation included the addition of valuable new food items into the diets of people in such widely separated regions as Ireland, China, and sub-Saharan- Africa.For the”new,”American world, the most significant transformation involved the deadly effects of Afro-Eurasian diseases among its peoples, which in turn helped pave the way for imperial conquest by Europeans. After two centuries of what is now known as the Columbian Exchange, both Old and New Worlds were transformed.