The Columbian Exchange

Before 1492Two very different ecosystems

Two different disease pools

Two sets of flora and fauna

Two sets of culturally

diverse peoples

“...all the trees were as different from ours as day from night, and so the fruits, the herbage, the rocks, and all things.”

-- Christopher Columbus

Two biological ecosystems interchanged to create a new world ecology.

According to historian Alfred Crosby, the exchange of plants, animals and pathogens between the two hemispheres was biologically “the most spectacular thing that has ever happened to humans," and he coined the phenomenon the Columbian ExchangeColumbian Exchange.

An Exchange of Pathogens

The smallpox virus

A Demographic Collapse

In Mexico alone, the native population fell from In Mexico alone, the native population fell from roughly 30 million in 1519 to only 3 million in 1568.roughly 30 million in 1519 to only 3 million in 1568.

Aztecs afflicted with Smallpox

Modern-day victims of smallpox

Livestock

A Plague of Sheep

Chickens and Eggs

The Cowboys of the Americas

Gaucho

VaqueroVaquero

CowboyCowboyLlaneroLlanero

The greatest impact of the Columbian Exchange was the

exchange of different food crops.Sweet Potatos

CassavaPotatosPotatos

The Exchange of Plants and AnimalsOriginally from the Western Hemisphere• Potato• Maize (corn)• Manioc (cassava, tapioca)• Sweet potato• Tomato• Cacao (chocolate)• Squash• Chili peppers • Pumpkin• Papaya• Guava• Tobacco• Avocado• Pineapple• Beans (most varieties, including

phaseolus vulgaris)• Peanuts• Certain cottons• Rubber• Turkeys

Originally from the Eastern Hemisphere

• Sugar• Olive oil• Various grains (Wheat, rice, rye,

barley, oats)• Grapes• Coffee• Horses• Cattle• Pigs• Goats• Sheep• Chickens• Various fruit trees (pear, apple,

peach, orange, lemon, pomegranate, fig, banana)

• Chick peas • Melons • Radishes• A wide variety of weeds and

grasses• Cauliflower• Cabbage

An Increase in Food Supply Helped Populations to Rise

The eventual result of all the exchanging of different foodcrops was a dramatic increase in food supply, which in turncaused a rise in population. How and why did this happen?An entirely new food plant or set of food plants permits theutilization of soils and seasons that have previously goneunused, thus causing a real jump in food production and,therefore, population. The benefits went both ways.

Some Tropical Plants from the Old World

Some Tropical Plants from the New World

Maize/Corn

Sugar, Tobacco and Slavery

Africans lament the loss of their fellow countrymen.

MAP 26.2 The Atlantic slave trade, 1500-1800.

The Poor Person’s Food

The PotatoThe Potato

The potato grows well in the temperate climate of northern Europe and produces three times as much food per unit of land as wheat or any other grain.

The Bank of England

Between 1781 and 1845, the Irish population doubled from four to eight million. Probably half of

this population depended on the potato for survival.

The Great Irish FamineOver one million died of starvation and disease, and almost two million emigrated to the United States and Britain.

The Columbian Exchange

The effects of the columbian exchange are still with us today.

Bit by bit, we are becoming more homogenized, and the world is becoming smaller.

Is the world growing more the same?