American Indian migration theory

Theory concerning the migration path of the first peoples of the Americas who are known to have migrated in waves from Asia and dispersed throughout North and South America, their descendants being the American Indians. Two theories predominate concerning their migration path. An ‘overland’ theory suggests the use of the Beringia land bridge between Siberia and Alaska (now the Bering Sea) exposed during the last ice age 20–30,000 years ago, and gradual dispersal to South America. A ‘by-sea’ theory suggests that the first Asians travelled by boat down the Pacific coast 15–20,000 years ago. The earliest reliably dated archaeological sites in North America are 13,000–14,000 years old. In South America the earliest sites are generally 12,000–13,000 years old, but discoveries made in 1989 indicate habitation 35,000–40,000 years ago.

The popularity of the ‘overland’ and ‘by-sea’ theories change and new theories arise as further artefacts and human remains are discovered.