How did the movement of people into North America during the ice age change history

The settlement of the Americas began when Paleolithic hunter-gatherers entered North America from the North Asian Mammoth steppe via the Beringia land bridge, which had formed between northeastern Siberia and western Alaska due to the lowering of sea level during the Last Glacial Maximum. Due to this migration the mammoths were hunted to extinction, most of Americas animals that were alive before they entered the Americas were eventually hunted to extinction

b. ensure mutual protection from communism.

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