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From: "Dienekes Pontikos" <>
Subject: Re: [DNA] Age of R1b
Date: Thu, 4 Sep 2008 11:46:12 +0300
References: <ea3bd9560809012041t38bdc5ei6bb25a9ea591aa88@mail.gmail.com>
In-Reply-To: <ea3bd9560809012041t38bdc5ei6bb25a9ea591aa88@mail.gmail.com>


On Tue, Sep 2, 2008 at 6:41 AM, David Faux <> wrote:
> As to the "infamous Zhivotovsky coefficients", I know you are a biochemist
> and respected scientist - but I don't know you. I correspond with Peter
> Underhill a co-author of the Zhivotovsky, Underhill and Feldman (2006)
> paper, and I have the utmost respect for his work.

One piece of evidence to consider:

http://dienekes.blogspot.com/2008/08/sicilian-y-chromosomes-greek-and-north.html

in which Dr. Underhill is a co-author, uses germline mutation rates.

http://dienekes.blogspot.com/2008/08/new-y-chromosome-haplogroup-e-m293.html

in which Dr. Underhill is also a co-author, uses the "evolutionary rate".

My own analysis has led me to believe that for large haplogroups
variance accumulates nearer to the germline rate and not to the
"evolutionary rate":

http://dienekes.blogspot.com/2008/07/how-y-str-variance-accumulates-comment.html

and the source code for my experiments is publically available:

http://dienekes.blogspot.com/2008/08/y-chromosome-microsatellite-genealogy.html

PS: As for R1b, I am agnostic until I see a representative sampling of
its variance and a comprehensive study of its phylogeography. There
are at least three different pieces of evidence that can be used to
estimate the age of a haplogroup:

(1) Y-STR variation. This points to a relatively young age in the
_available_ samples.
(2) Geographical extent. Older haplogroups have had more time to
spread to wider regions. This points to a relatively old age.
(3) Haplogroup size. Older haplogroups have had more time to grow to
larger numbers. This also points to a relatively old age.

So, in my opinion, the available evidence is contradictory. The
contradiction can be resolved in a number of different ways (e.g.
Y-STRs behave differently than thought, or there was positive
selection). In a few years, when whole Y-chromosomes will be routinely
sequenced, and ancient DNA results will be more easy to acquire, we
will be able to solve the puzzle.

--

Dienekes' Anthropology Blog
http://dienekes.blogspot.com


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