GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2010-02 > 1266017744
From: (John Chandler)
Subject: Re: [DNA] haplogroups
Date: Fri, 12 Feb 2010 18:35:44 -0500
In-Reply-To: <COL116-W2679B03695C39A135CB65CE44D0@phx.gbl> (message from NeldaPercival on Fri, 12 Feb 2010 16:23:10 -0600)
> YDNA Adam is thought to be the father of all living males
> today.. the thought is that there were other males living when he
> lived but that those other male lines daughtered out.
Not exactly. Y Adam is *defined* as the MRCA of all living male humans.
The *thought* is that Y Adam was an early modern-type human, but there
is some diversity of opinion on exactly when he lived. It is clear, at
least, that he was not the only living modern-type male in his time and
> and the assignment of different grouping names... "R" "N" (what
> ever) and such; I thought depended on the scientific group who
> discovered them..
Maybe you are referring to the names of SNPs, such as M153 or L21,
which are named with initial letters according to the group that
discovered the mutations. The current scheme of Y haplogroup names
was constructed systematically to replace the hodge-podge of previous
systems of nomenclature. The letters were assigned in order across a
"tree" showing the genealogy of the groups, as understood at the time.
The decisions of where to bestow "major group" status by a capital
letter were somewhat arbitrary, but the scheme is simple and easy to