In South America the eastern highlands are divided into two main pieces. To the north are the Guiana Highlands , and to the south are the Brazilian Highlands . Continuing the parallels between North America and South America, both continents have large lowlands in their center that are drained by major river systems. Its parallel in North America would be the Mississippi-Ohio river system. A key difference between the continents, though, is the fact that the Amazon system drains a sparcely populated tropical area, while the Midwest is a well populated middle-latitude heartland of the United States.
Latitudes are also different.
Most of South America lies in the tropics , whereas much of North America is middle-latitude in location. The South American continent is relatively narrow at higher latitudes. Thus higher-latitude locations in South America tend to be closer to an ocean than comparable locations in North America. Since water heats and cools relatively slowly this proximity to water lessens the temperature extremes that one finds in southern South America.