The flow was highly important because it cultivated large areas of land. This meant there would be a food surplus, a bonus to both the Natives and Europeans. Horses would pull the plows across the land, saving time and physical labor. Guns and knives were also introduced to the Natives. Although they already had knives, the knives were not as strong as European knives, which were made out of steel and iron. When Natives witnessed the destructiveness of guns, they realized they would now be able to hunt larger animals and do it more effectively due to the horses they used as a means of transportation. Europeans used the Natives fascination with guns against them. Europeans were now able to exploit them because they had an advantage over the Natives. The Natives became dependent on the Europeans for stronger weapons, which allowed the Europeans to receive more goods (Columbus 1493). The Colombian Exchange is sometimes overlooked for the positive things that it brought. However, the Colombian Exchange also transmitted diseases, which had devastating effects to both the Old and New World. Common Old World diseases included smallpox, measles, malaria, yellow fever, influenza, and chicken pox. New World diseases included syphilis, polio, hepatitis, and encephalitis. The natives were extremely prone to new diseased. Nearly all European diseases were contracted by air and touch which made it easier for diseases to