The
Americas are the lands of the
Western hemisphere or
New World, consisting of the
continents of
North America and
South America with their associated
islands and
regions. The Americas cover 8.3% of the
Earth's total surface area (28.4% of its land area) and contain about 14% of the
human population (about 900 million people). The Americas may instead be referred to as
America;
[1][2] however,
America may be ambiguous, as it can refer either to the entire landmass or to the
United States of America.
South America broke off from the west of the supercontinent Gondwanaland around 135 million years ago (Ma), forming its own continent.[3] Starting around 15 Ma, the collision of the Caribbean Plate and the Pacific Plate resulted in a series of volcanoes along the border that created a number of islands. The gaps in the archipelago of Central America filled in with material eroded off North America and South America, plus new land created by continued volcanism. By 3 Ma, the continents of North America and South America were linked by the Isthmus of Panama, thereby forming the single landmass of the Americas.[4]
Archaeological finds establish the widespread presence of the Clovis culture in North America and South America around 10,000 BCE.[5] Whether this is the first migration of humans into North America and South America is disputed, with alternative theories holding that humans arrived in North America and South America as early as around 40,000 BCE.
The Inuit migrated into the Arctic section of North America in another wave of migration, arriving around 1000 CE.[6] Around the same time as the Inuit migrated into North America, Viking settlers began arriving in Greenland in 982 and Vinland shortly thereafter.[7] The Viking settlers quickly abandoned Vinland, and disappeared from Greenland by 1500.[8]
