The Ice-Free Corridor hypothesis (or IFC) has been a reasonable theory for how human colonization of the American continents occurred since at least the 1930s. ... In 1840, Louis Agassiz put forward his theory that the continents had been covered by glacial ice at several points in our ancient history
Explanation:
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Answer: The Ice-Free Corridor hypothesis or IFC has been a reasonable theory for how human colonization of the American continents occurred since at least the 1930s. ... In 1840, Louis Agassiz put forward his theory that the continents had been covered by glacial ice at several points in our ancient history.
