Both the New World and the Old World influenced each other heavily in what is called the Colombian Exchange. Diseases such as smallpox wiped out entire villages of Native Americans—around ninety percent of the Native Americans in the New World died due to disease brought from the Old World. These weakened strong empires enough so that small groups of Europeans could wipe out civilizations that had existed for hundreds of years.
The Spanish, realizing the power of the horse, initially forbade Native Americans from owning them. The horses soon escaped, and Native Americans on the Plains soon became adept riders, using the horse to hunt buffalo and in war. The arrival of the horse led to the Cheyenne and Lakota becoming strong Plains tribes.
Pigs also escaped from farmers and became feral hogs. Having no natural predators, these pigs soon reproduced and destroyed native crops. Today feral hogs remain nuisance animals throughout the southeastern United States. Europeans also brought wheat...
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