Columbian Exchange

In his 1972 book, The Columbian Exchange: Biological and Cultural Consequences of 1492, Alfred Crosby provided a view of the Atlantic System through the lens of environmental history and biology.  It is among the first works to usher in a new environmental approach to history.  Crosby's entry for the Encylopedia; of Earth, "Columbian exchange: plants, animals, and disease between the Old and New World,"  is a useful introduction.  For a more up to date review, see John F. Richards,  The Undending Frontier:  An Environmental History of the Early Modern World. (University of California Press, 2006),  Ch. 9, "The Columbian Exchange; The West Indies." 

Crosby's thesis was the following:

1) The most significant transformations brought about by Columbus' four voyages and colonization of the Caribbean region from 1492 through 1504 were biological, not social or political.   The transfer of organisms and disease, plants and livestock between Europe ("Old World") and the Americas ("New World") had devastating and wide sweeping ramifications for the First Peoples of the Americas. It also altered the diets and resulted in other diseases that affected Europe as well.

2) Prior to the emergence of the modern world system that emerged after the Atlantic crossings after 1492, the world was distinguished by a remarkable environmental and genetic divergence.  That divergence was rapidly transformed after the conquest of the Americas by the Spanish and Portuguese from the late 15th century onward.

While there are dozens of animals and crops, organisms and diseases that were transferred with dramatic consequences (see list at Wikipedia entry on the Columbian Exchange), some of the major representatives are summarized below by Crosby.

Animals, Plants and Disease introduced from Europe to the Americas:
Animals                      Plants                   Disease
1)  Horses.                  Wheat                   Smallpox and measles
2)  Pigs                        Sugar                    Influenza
3)  Goats/sheep           Coffee                   Typhoiod
4)  Pigs                        Cotton                   Bubonic Plague
5)  Cows                     Fruits/vegetables    Cholera, malaria, yellow fever

Animals, Plants and Disease introduced from Americas back to Europe:
Animals                      Plants                   Disease
1) Guinea Pig               Cocoa/Chocolate   Syphilis
2) Mink                       Potato                    Chagas / Chargas' disease
3) Turkey                    Tomato
4) Llamas                    Corn/Maize
5) Ilpacas                    Tobacco

The overall impact of the Columbian Exchange resulted in a massive depopulation of the First Peoples who inhabited the Americas.  The effect of the diseases as well as genocidal policies of the Spanish and other European colonists resulted in a loss of population from 54 million in 1500 to 13.5 million in 1570. That is a staggering depopulation of approximately 75 percent.  This depopulation explains in part why Europeans imported millions of slaves from Africa as labor in mines and on plantationss to replace these depopulated areas.

For example in the valley of Mexico, the heart of the capital of the Aztecs, the local indigenous population estimated at 1.5 million in 1519 was reduced toabout 70,000 in 1650, but recovered to around 275,000 in 1800 (Benjamin, 2009, 174).

Cook, Noble David. Born to Die: Disease and New World Conquest, 1492-1650. Cambridge; New York: Cambridge University Press, 1998.
Crosby, Alfred W. The Columbian Exchange: Biological and Cultural Consequences of 1492, (1972; reissued 2003).
______________. "Columbian exchange: plants, animals, and disease between the Old and New World", in Encyclopedia of Earth. Eds. Cutler J. Cleveland.  Web.  Accessed April 7, 2012.
______________.  Ecological Imperialism: The Biological Expansion of Europe, 900-1900. Cambridge; New York: Cambridge University Press, 1986.
Denevan, William, M., ed. The Native Population of the Americas in 1492. 2nd ed. Madison: University of Wisconsin Press, 1992.
Díaz del Castillo, Bernal. Historia Verdadera de la Conquista de la Nueva España. Translated by A. P. Maudslay [The Discovery and Conquest of Mexico, 1517-1521]. New York: Farrar, Straus, and Cudahy, 1956. Reprint with new introduction by Hugh Thomas, Da Capo Press, 1996.
Melville, Elinor G. K. A Plague of Sheep: Environmental Consequences of the Conquest of Mexico. Cambridge; New York: Cambridge University Press, 1994.
Mintz, Sidney W. Sweetness and Power: The Place of Sugar in Modern History. New York: Viking, 1985.
Salaman, Redcliffe N. The History and Social Influence of the Potato. Cambridge; New York: Cambridge University Press, 1993.
Thornton, Russel. American Indian Holocaust and Survival: A Population History since 1492. Norman: University of Oklahoma Press, 1987.
Verano, John W., and Douglas H. Ubelaker, eds. Disease and Demography in the Americas. Washington, DC: Smithsonian Institution Press, 1992.