Migration
There are different theories about how the American continents became populated. The prevailing theory, the Land Bridge Theory, holds that the first inhabitants of Americas migrated from Asia across the Beringia. According to this theory, the first inhabitants of South America arrived from North America via the Panamanian isthmus.
Other theories hold that the first humans to reside in the Americas came across the Pacific Ocean from Oceania or across the Atlantic Ocean from Europe.
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