Like Markforever, I'd like to hear a little more basis than simply bald assertion. It should also be noted that "other creation stories from Mesopotamia" don't necessarily tell us much about what the Biblical text means--while there may be parallels, there are clearly other ways in which the Biblical text is self-consciously distinct, as would be expected when God is constantly telling the Israelites not to be like the surrounding nations.
More seriously, she seems to be wrenching one word out of its context and playing with it all by itself, ignoring how that word is used elsewhere in the exact same story, not to mention elsewhere in the Pentateuch and the Hebrew Bible as a whole, and ignoring the rest of the chapter. For instance, 1:21: "God created (bara) great whales..." 1:27: "God created (bara) man in his own image." How does "separated" as a meaning make any sense in these verses? Clearly God is doing a lot of separating (light from darkness, land and seas, etc.), but he is first creating things that need to be separated: "Let there be light" (bara not used there). And there's another perfectly good word for separating that is actually being used in the text: "badal" (vv. 4, 6, 7, 14, 18). Far more words than just "bara" have to be re-imagined for her new cosmology to be internally consistent.
In the final analysis, this looks like just another publicity stunt--make an outlandish claim that supposedly upends everything people have always known to be true about Christianity and/or Judaism and the credulous, secularist, and religiously illiterate press fawn all over it (see almost every Easter cover story on Time and Newsweek), eager for a new way to show believers to be the drooling idiots they've always known them to be.
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