In James Michner’s book, Centennial, there was an estimate as to how long it took for humans to cross into North America from Asia and then reach the tip of South America.
That guess was 15,000 years. This was an average of 8 years a generation.
The reasons for moving on were Enemies and loss of food.
Michner did not mention Giant Armadillos.
Excellent, truly Excellent. The Book Report, an often overlooked literary genre, perfected!