I believe that Adam's ancestors were wiped out, but not by the flood. I believe they were wiped out because, lacking the spark of intellect that came with the soul breathed into Adam, they weren't equipped to compete with Adam and his descendents for the same environmental niches.
Hummmm, Cro magnon vs Neanderthal....
The grudge match was probably in my home town. I had a neighbor that fit the wiki-description of the neanderthal to a tee...height, appearance and all. Oh, and he was a good hunter too. And there were a few fights.
