Exactly. We know genetically that we did not descend from a single set of parents - rather that we may have actually descended from several strains of humanity all emerging around the same time, such as Homo Neanderthalensis, which was genetically subsumed.
We know the Flood never happened, because the story is plagiarized from the Epic of Gilgamesh, written 1000 years BEFORE Genesis was written and which originally tells the tale of a river flood or possible tsunami, not a global Flood.
The rest of the Old Testament is likewise rife with impossible occurrences, such as the sun refusing to move while the Israelites fought - we know that the "movement" of the sun is actually a result of the rotation of the earth - for the sun to appear to stop would mean the earth stopped revolving, and the immediate inertial winds this would have caused would have been in excess of 200 mph all over the world.
The "Bible" is a book of myths.