[Avodah] Mitochondrial DNA and the Mabul

[Arie Folger]

Dear Ovedim,

I have been sitting on this post for a very long time (actually, I
just write it now, but I was planning to for several years). In the
past, we have often discussed how to understand the Mabul, whether the
Mabul was fully covering the earth, or whether, as IIRC Reish Lakish
has it, it excluded EY, or whether, as Rav Henkin the Younger, Shlita,
argues, only the mountains that are tachat kol hashamayim, to exclude
those that are too high for being tachat kol hashamayim.

Other questions were also raised, such as lack of sedimental layers,
of the two favorite objections our last master RMB likes to cite, tree
rings, continuous cultures before and after the presumed age of the
Mabul.

Most of the solutions however ultimately assume that even if the flood
was local or not totally global, it did wipe out humanity.

That does not answer the cultural objection I cite from RMB above, but
many people will consider archaeology a soft science and not consider
its evidence to weigh that heavily. After all, archaeologists really
do engage in much speculation with scant available evidence.

However, there is another kind of evidence that would very much
question the human discontinuity except for family Noach. Brian Sykes,
the geneticists who reportedly developed this kind of genetic
analysis, has studied the mitochondrial DNA of contemporary people. By
correlating know rates of mutations to the differences between
populations, one can make a fairly solid educated guess as to how
related different people are. As mitochondrial DNA is inherited from
the mother only (similar analyses with Y chromosome sequencing
confirms his findings on the paternal side), it implies that one can
guess when people had their last common great great n^x grandmother.

Over time, some women have no kids, or only sons, and thus their
mitochondrial DNA line becomes extinct. Over hundreds of generations,
that extinguishes an awful lot of lines, and with his analysis, he
finds "seven mothers" of Europeans, hence the title of his book, the
Seven Daughters of Eve. The differences between those individuals are
fairly large, and hence it is useful to consider those women genetic
foremothers.

The number of genetic foremothers is irrelevant here for our purposes,
but it is relevant that this analysis argues, using hard scientific
facts, that there is human genetic continuity for much more than since
the Mabul, and too much diversity for it to have developed only since
then.

I was toying with the idea that the ladies of family Noach were each
very genetically diverse from the other, so that mitochondrial
diversity can be attributed to that, a Divine act of social
engineering, but AFAIU, this would be insufficient to account for the
full gamit of mitochondrial diversity, and doesn't explain
y-chromosome diversity at all.

I am hoping the responses will not only be fancy new ways of
understanding our trusted sources, but rather that scientists among
the chevre will point out where the above picture is wrong, or right.
Perhaps the book is a hoax debunked by other scientists, or perhaps I
misunderstood it, or perhaps the numbers are off, or perhaps it has
all been confirmed and is a solid question that needs solid answers. I
look forward reading your responses.

Gmar chatimah tovah,
Shabbat shalom,

-- 
Arie Folger,
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