Final answer:
According to the coastal migration theory, people first arrived in North America by migrating by land and sea from South America. This theory is supported by archaeological evidence and sites in South America that predate the Clovis sites in North America.
Step-by-step explanation:
The first people who arrived in North America migrated by land and sea from South America to North America, according to research and archaeological evidence. This is known as the coastal migration theory, which suggests that these early inhabitants followed the coast of land across Asia and the Bering Land Bridge. They then traveled down the coast of North America all the way to South America, utilizing the rich marine environment along the way for their sustenance. The coastal migration theory is supported by archaeological sites in South America that predate the North American Clovis sites. Examples of such sites include Monte Verde in Chile and Taima-Taima in Venezuela.