Final answer:
The nomads who eventually came to be known as American Indians first reached the continent by crossing the Bering Land Bridge during the last Ice Age. They gradually spread across the continent, adapting to different environments and developing unique cultures over time.
Step-by-step explanation:
The nomads who eventually came to be known as American Indians first reached the continent by crossing the Bering Land Bridge.
Approximately 20,000 years ago, during the last Ice Age, sea levels were much lower, exposing a land bridge that connected Asia and North America. This land bridge, known as the Bering Land Bridge or Beringia, allowed nomadic groups to migrate from Asia to America. These nomads gradually spread across the continent, adapting to different environments and developing unique cultures over time.
For example, the Paleo-Indians were the earliest known inhabitants of America. They relied on hunting large mammals such as mammoths and mastodons for survival. As the climate changed and the large mammals went extinct, different Native American cultures emerged, including the agricultural civilizations of the Mayans, Incas, and Aztecs in Central and South America.
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