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Archiver > GENEALOGY-DNA > 2009-12 > 1260209309


From: David Faux <>
Subject: Re: [DNA] R-U152 and R-L21 on the European Continent
Date: Mon, 7 Dec 2009 10:08:29 -0800
References: <59915.56775.qm@web81103.mail.mud.yahoo.com><06F79C98-398C-4200-8D9C-5BA976ABD233@vizachero.com><ea3bd9560912061730y581da805v54dec4a73733efee@mail.gmail.com><006701ca76ef$d0ab50b0$7201f210$@org>
In-Reply-To: <006701ca76ef$d0ab50b0$7201f210$@org>


In speaking with one of the parties about a year ago, I got the distinct
impression that Zhiv is viewed within expanding circles in the field of
population genetics as "gifted" in the statistical arena, having a solid and
persuasive rationale to back up his figures, and one whose technique
calibrates well with known human events (e.g., the migration of the Maori to
New Zealand). Hence the creation of the "evolutionary - effective" mutation
rate which differs from the observed germline rate by a factor of over 3.
He was well aware of the other viewpoints but none the less believed that
Zhiv was on the right track. I would guess that having the support of
another heavy weight population geneticist of the status of Dr. Hammer will
further entrench the "ZUF rates" to the point where it will take take a lot
of heavy machinery to move this group to another camp.

Most genetic genealogists appear to have been persuaded by Ken, Anatole etc.
(very well respected in their fields) to the point where there are similar
tendencies of digging in one's heels with respect to projecting germline
rates back in time (using interclade estimates or similar statistical
manipulations).

Perhaps it is necessary to turn to the chemistry of the system to understand
why it is a weak assumption to take a snapshot of what is evident from today
(e.g., via father - son observation of mutation rates), and say that it must
have been so in the past. The more I learn about the process of
methylation, and the role of histones in gene expression and other genetic
mechanisms, the more it becomes apparent that environmental factors (which
of course have not been constant over the eons) can impact on what occurs at
the genomic level. Basically, in my view, without considering epigentics
the snapshot is going to be very blurry and the interpretation of what is
seen could be out and out wrong. Mutation rates may have to consider both
time and place. Boil it down and what I am saying is that the confidence
interval of any interclade date proposed is likely so large as to afford a
very high probability of being vastly off the mark when sailing in the
waters beyond "genealogical time" (e.g., 1300 AD or so when surnames were
adopted).

Dr. Zhivotovsky has at least offered one approach that would compensate to a
degree for the above, but I would argue that using a single figure for such
a complex process may "work" some of the time and for some locations, but
surely it is not able to capture the spectrum of change from the "Dark Ages"
through the mists of early time (e.g., Paleolithic).

David K. Faux.

On Sun, Dec 6, 2009 at 7:46 PM, Lawrence Mayka <> wrote:

> It's unfortunate that the Zhivotovsky camp has not yet been confronted with
> Nordtvedt's interclade technique (of calculating lower and upper bounds on
> the age of a haplogroup), which removes any possible argument in favor of
> fudge factors.
>
> > From: [mailto:genealogy-dna-
> > ] On Behalf Of David Faux
> > Now Michael Hammer has come on board,
> > along with Peter Underhill some time ago, with Zhivotovsky in terms of
> > dating clade ages - so multiply by 3.6 - or not.
>
>
>


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