Some anthropologists believe humans first migrated to the western hemisphere from Siberia about 35,000 years ago via a land bridge; and some anthropologists suggest humans may have followed the northern Pacific coast by boat down to the Americas from Siberia. Regardless of how they got to the continent, it is believed that as these early humans trickled into the continent, and split into branches that spread south and east. By at least 4,200 years ago descendants of these early humans had migrated to populate the entire Western Hemisphere… but why did these early people (who, in the fifteenth century, Christopher Columbus misnamed “Indians”) migrate in the first place? … The answer is quite simple: some were fleeing perceived intolerable living conditions and others were in search of food. In reality, overall, they were evolving and surviving in an unforgiving world.