While I have no specific evidence of the Noah’s ark theory, the very small genetic diversity of humans has led some scientists to speculate that perhaps at some point long ago in human history, the human population dwindled to a few individuals before rebounding back to a large population. (I read this story several months ago but I’m having trouble finding it again, I’ll try to find a link when I get more time). The article went on to demonstrate some “bottleneck” in the human lineage almost definitely occured.
It would not be unreasonable to speculate a flooding event could have depleted an already small population of humans perhaps when people only lived in central Africa. A catastrophic event which killed perhaps 90% of the known world would certainly be remembered (through storytelling) for many, many generations. Whether or not this was the only population of humans wouldn’t matter if the story continued even as the populations met and combined. Could this type of event still be “remembered” through the story of Noah’s ark? Hard to imagine a story continuing for hundreds of thousands of years…
Edit: Found some links:
http://en.wikipedia.org/wiki/Human
From the article:
Geneticists Lynn Jorde and Henry Harpending of the University of Utah proposed that the variation in human DNA is minute compared to that of other species; and that during the Late Pleistocene, the population was reduced to a small number of breeding pairs (no more than 10,000), resulting in a very small residual gene pool. Various reasons for this possible bottleneck have been postulated, the most popular is called the Toba catastrophe theory.
http://www-personal.umich.edu/~wolpoff/Papers/Bottlenecks.PDF#search=‘human lineage bottleneck’
From the article:
There are many reasons to believe that there may
have been a number of severe population size bottlenecks
on the lineage leading to living humans, principally
because of the many speciation events that must
have occurred.
Also:
Based on autosomal evidence
from several gene systems, we may rule out such
a bottleneck at times more recent than 1.5 Myr (this
date, the time when significant expansion of the human
range out of Africa first began, can be estimated from
the autosomal data presented in table 1). No date more
recent than this is compatible with known neutral nuclear
variation. However, nonmolecular sources of information
must become more important as we consider
demographic events far in the past.
Therefore, considered together, nuclear data allow
bottlenecks within a narrow range around 2 MYA, a
range of possibilities that is fully compatible with the
fossil and archaeological records.
Noah’s ark, a two-million year old story?