In the beginning, after the great flood, it was a muskrat who helped remake the earth.
--The Night Watchman, Louis Erdrich
There, you see? Even the Turtle Mountain Band of Chippewa Indians had a flood story. In fact, nearly every native culture around the world has an ancient flood story/mythology at the core of its identity which has endured through the ages. It seems to me nothing more than logical assumption that some such sort of worldwide event did indeed occur and was ingrained in universal memory both as a real event of cataclysmic destruction and as a miraculous regeneration of humankind in the aftermath. In the Chippewa myth, it is the muskrat (wazhashkag) that ushers in this new area of reformation/reimagination/regeneration. In other tribes it is a crow; in others a coyote; in still others a human being; each creature endowed with powers that are salvific and wisdom that is otherworldly. This is the way the world works, this is the way time works, and mythology is the record both of real event and numinous import.