GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2006-04 > 1145980177


From: ellen Levy <>
Subject: RE: [DNA] irish origins and myths
Date: Tue, 25 Apr 2006 08:49:37 -0700 (PDT)
In-Reply-To: <20060425023038.FBNB1358.omta03sl.mx.bigpond.com@DINOSAUR>


Brian:

I'm pleased that you went to the actual studies to
critique them. There has been a lot of criticism of
the assertions of these aDNA studies, but not a lot of
direct referencing to them. Kind of like me trying to
build an argument in court without reference to any of
the case law.

Can you cite a reference to this information from
Zilhao?

The problem with N1a is that we don't know if it is
associated with the Paleolithic (and hence
hunter-gatherers) or the Neolithic (and hence
agriculturalists). The archaeological data does
provide some important clues, but Haak essentially
ignores them and jumbles all the burials together,
calling them "Neolithic."

What you caught on to, though you were referring more
to the HV data, was that 23,000 year old Paleolithic
skeleton belongs to haplogroup N (an ancestral group
to the N1a that Haak finds about 15,000 years later).
By the way, the author notes that HV and pre-HV isn't
particular prevelant among Europeans today either, but
is among Middle Easterners. The same can be said for
N*. Thus, there appears from this study to be a
European Paleolithic = Middle Eastern link. However,
since current population data can be misleading, it
would be essential to test prehistoric Middle Eastern
remains to see if they also contain N* or HV results.

So the bottom line is that N1a could easily represent
a Paleolithic lineage that has gone nearly extinct, as
opposed to a Neolithic one. In any case, the lineage
does not occur today in a similar frequency to N1a's
occurence in the past. Even haplogroup H appears to
have undergone frequency changes.

And yes, in my opinion, we are seeing lineage
extinctions. We know this because a similar aDNA
study on Central Asian remains found N1a as well, but
none in what is believed to be the current descendant
population. It's there, then it's gone.

What is causing this discontinuity from prehistoric to
contemporary groups (and I'm not arguing for a
complete disconnect, just significant differences in
frequency and haplotypes from past to present)? Most
likely: Evolution.

The idea that evolutionary processes have not been
having a significant impact on post-Neolithic
populations has been called into question by these
studies. As Alzualde writes:

"...Our data on ancient DNA (as well as those of
Vernesi et al 2004) reveal a discontinuity between
prehistoric and present-day populations, which leads
use to reconsider the limitations involved in the
reconstruction of evolutionary history on the basis of
the genetic patterns of present-day populations."

Ellen Coffman


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