[meandog]

Why leave a virtual paradise where the food grows on trees and bushes, the forest floor makes a comfortable bed, the water runs clear and plentiful and time clocks are millenia in the unanticipated future?

I dunno, I wonder why Peary and Byrd explored the arctic, Admunsen the antarctic, why Hillary climbed Everest, why Burton explored the source of the Nile and why Stanley looked for Livingston...because it was there?

[Old Professer]

Totally out of the question — the earliest man had no knowledge of his whereabouts or that there was even a larger world out there.

As foragers they likey traveled only as far as daylight would allow a roundtrip.