Final answer:
The most accepted 17th- and 18th-century explanation for Native American origins was the Bering Land Bridge migration model, where people migrated from Siberia to Alaska during the last ice age. This was a time of significant cultural transitions for the Native Americans, who faced both European colonization and changed living conditions.
Step-by-step explanation:
In the 17th and 18th centuries, European scientists and archaeologists sought to explain the identity and history of Native Americans. The most widely accepted explanation was the Bering Land Bridge migration model. This theory proposed that during the last ice age, people migrated from Siberia to Alaska across a land bridge exposed by lower sea levels due to massive glacial formations. These migrations, spanning from roughly 10,000 to 14,000 years before the present, followed the Pleistocene megafauna across what is now the Bering Strait.
Additionally, during this period, European colonization had a significant impact on the lives of the native inhabitants. Many died from European diseases to which they had no immunity, while others adapted by incorporating European trade goods and changing their ways of living. However, these exchanges and adaptations often led to dependency on European items and loss of control over their lands and resources.