GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2006-12 > 1165587698


From: Alan R <>
Subject: [DNA] Ellen's Paper
Date: Fri, 8 Dec 2006 14:21:38 +0000 (GMT)


The idea of selection creating the modern haplotype
distribution is interesting possible alternative or at
least a factor. If this selection is based on diet,
climate etc, you cannot simply look at a map and see
the common thread in areas with the same predominant
haplotypes. Diet is very complex because each area
passed through several dietary phases over the last
10,000 years and the timing and details vary.

Looking at Atlantic R1b distribution, it is true that
several of these areas have vaguely common dietary
histories. All remained hunter gatherers for a little
longer than most and they may have been more of an
emphasis on marine and riverine sources than
elsewhere. Farming came a little late to these areas.
In later prehistoric times it is also clear that
these Atlantic areas were mostly pastoral. Also,
certainly the Atlantic areas of the British Isles
became very much a dairy economy (think
Heidi)throughout most of historical times and did not
develop the peasant bread economy of much of Europe.
Finally, it is well known that marginal areas like
western Ireland and highland Scotland then adopted a
potato and milk diet which actually, prior to the
famine, provided better nutrition than was normal (the
Irish are thought to have been the tallest in Europe
in the Georgian era). The long-term common theme here
is a lack of reliance on cereals. This set at least
much of the Atlantic area apart from much of the rest
of Europe.

You wonder if hardship was a selective factor-western
Ireland, the Scottish highlands and the Basques
country in the Pyrenees were poor areas with endemic
small scale clan violence and all three areas were
associated with tough clannish ultra-hardy types!

That said, I am not convinced by the selection idea.
There are other areas which went through similar
dietary phases but do not share the same haplotype
proportions. It is possibly a factor but whether a
minor one or significant I am not sure. I would still
favour the main reason for distribution of Atlantic
R1b being survival of ancient lineages through
isolation from the main east-west movements of later
times. I have a theory that the early Neolithic
burials tested for mtDNA may represent intrusive
lineages that were rather different than the average
member of the surrounding population. The idea that
the Neolithic incomers were minority pioneers that
subsequently were swamped by the locals copying them
and taking up farming is popular among archaeologists
at present. This could explain both the lack of
classic SE European Neolithic genes in NW Europe as
well as the odd mtDNA gentics of the Neolithic
burials.

Alan


This thread: