Final answer:
The Bering Land Bridge theory states that nomadic peoples originally traveled to the Americas by foot across a land bridge called the Bering Land Bridge.
Step-by-step explanation:
The theory mentioned in this question is the Bering Land Bridge theory. According to this theory, it is believed that nomadic peoples traveled to the Americas by foot across a land bridge called the Bering Land Bridge. This land bridge connected what is now northeast Asia to present-day Alaska. They crossed over the Bering Strait, which is the narrow body of water between these two landmasses. This migration is thought to have happened during the last Ice Age when sea levels were lower and made the crossing possible.
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