Huh? No. Who says the Sumerian account had the details right or didn't deviate from what actually happened over time?
And it looks like you didn't read my paragraph about how the flood account wasn't directly inspired by God, as in God wasn't the one telling the story, either.
I don't know enough to answer your questions but I want to point out that living as a hunter gatherer does not equate to milling around like apes for hundreds of thousands of years.
Hunter Gatherers have culture and raise families just like "Civilized Man" does. They are/were Homo Sapiens after all.
Before the advent of agriculture, humanity spread across the globe, adapted to new climates and invented new technologies. It's not like nothing was going on before people started farming.
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