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Archiver > GENEALOGY-DNA > 2006-07 > 1152031876


From:
Subject: Re: [DNA] Jewish Q among Hispanics and Italians [tree diagrams]
Date: Tue, 4 Jul 2006 12:51:16 EDT


In a message dated 7/4/2006 8:55:58 AM Pacific Daylight Time,
writes:

> My guess is that Hap-Q and Hap-R are probably about the same age as the
> they
> are both derived from Hap-P. Therefore both haplogroups Q and R will
> probably be found to very diverse rich and complex SNPs patterns.

Just a side note on ages of haplogroups -- the X-axis on most phylogenetic
tree diagrams is not proportional to time, so the fact that Q and R line up
vertically is not a clue to their relative ages. The only thing we can determine
is that they are both younger than P. The same tree structure could be
displayed as a network diagram (central circles with subgroups radiating off them),
which doesn't seduce people into thinking about time scales.

Another benefit of network diagrams is that the size of the circle is
proportional to the number of samples. Thus the central circle for R1b1c will be
quite large, and the various subclades radiating off the center will be quite
small. I think people are often disappointed when they do a subclade test (the
same for mtDNA Haplogroup H) -- the tree diagram seduces them into thinking they
have a good chance of belonging to one of the many subclades, because the
branches appear to have equal weight.

Just some stray thoughts -- not really part of this thread!

Ann Turner


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