The Columbian Exchange had both negative and positive effects. Some of the positive effects include the exchange of technology. The introduction of the plow transformed farming because it increased cultivation and food production to the benefit of both Native Americans and the Europeans.
The primary positive effect of the Columbian exchange was increased food supply and nutrients to the populations of both areas. Europe probably benefited more than the Americas with the introduction of potatoes and maize (corn) to that continent. The end result was a decided improvement in the diet of most Europeans as well as a decline in the overall cost of food.
Just as Europe benefited from the exchange, so the Americas suffered. Although many useful crops such as wheat, barley and rye and livestock such as cattle and swine were introduced, so also were infectious diseases such as measles and smallpox to which the native population had no immunity. Fully 90 per cent of the pre-Columbian population of the Americas had disappeared within 100 years of Columbus' landing.
