<P> South America has an area of 17,840,000 square kilometers (6,890,000 sq mi). Its population as of 2016 has been estimated at more than 420 million . South America ranks fourth in area (after Asia, Africa, and North America) and fifth in population (after Asia, Africa, Europe, and North America). Brazil is by far the most populous South American country, with more than half of the continent's population, followed by Colombia, Argentina, Venezuela and Peru . In recent decades Brazil has also concentrated half of the region's GDP and has become a first regional power . </P> <P> Most of the population lives near the continent's western or eastern coasts while the interior and the far south are sparsely populated . The geography of western South America is dominated by the Andes mountains; in contrast, the eastern part contains both highland regions and large lowlands where rivers such as the Amazon, Orinoco, and Paraná flow . Most of the continent lies in the tropics . </P> <P> The continent's cultural and ethnic outlook has its origin with the interaction of indigenous peoples with European conquerors and immigrants and, more locally, with African slaves . Given a long history of colonialism, the overwhelming majority of South Americans speak Portuguese or Spanish, and societies and states commonly reflect Western traditions . </P> <P> South America occupies the southern portion of the Americas . The continent is generally delimited on the northwest by the Darién watershed along the Colombia--Panama border, although some may consider the border instead to be the Panama Canal . Geopolitically and geographically all of Panama--including the segment east of the Panama Canal in the isthmus--is typically included in North America alone and among the countries of Central America . Almost all of mainland South America sits on the South American Plate . </P>

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