I am pretty certain he is talking about WAY before that. Before the Biblical timeframe, before Gilgamesh and before Judaism. Ancient cultures like the ones in South America, Africa and the South Pacific and Southeast Asia.
right..the flood that inspired these stories is most likely a global happening that occurred after the last ice age and then maybe smaller events after the 'mini' ice age that came later
both of those happened 4-5 thousand yrs before Sumerian or Egyptian culture (that we know of)
but there were other mini cultures, local groups of farmers in the mid east and whatever the state of culture was in egypt at the time (talking like approx. 8,000 bce)
these ppl would have had stories passes on to them from those who were alive at the time of the "flood(s)". the stories got passed down, gen to gen, village to village, etc
when we get to writing with cuneiform and other methods, it is not till much later and then those verbal stories were put into print
these stories have tremendous staying power. for example, we still make tv shows and movies, books about the ancient religion of the greeks and anatolia; the whole pantheon of gods and heroes. no longer a religion and they were verbal traditions before any greek wrote them down, but even now, 3000 yrs later, we are still telling those stories.
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as far as places that seem to been flooded on sudden-an actual flood. it is believed that after sea levels, and glacial melt got so high for so long slowly, then there were incidents of quick massive flooding
it is thought that the black sea was oince much much smaller and had no outlet to the med. as it does now.when the med's levels rose high enough the waters burst through and smaller and smaller land bridge between anatolia and europe creating an actual flood
i am sure similar things like that happened all over the world and affected every culture that was in being at the time --the red sea, the persian gulf, the caribean, england and ireland (interesting the theory on why no snakes in ireland is connected to this--the irish sea flooded during a time when europe was still too cold for snakes, the english channel did not flood till much later when Europe was warm enough for snakes) were once-recently, part of europe. the yellow sea between china and korea was prob all land till the ocean rose and flooded in.
maybe one day we will get ppl to the floors of all these places to make more aggressive explorations
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again,,someone make us a time machine