GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2008-12 > 1228874350


From: "Ken Nordtvedt" <>
Subject: Re: [DNA] Some thoughts about DNA survival
Date: Tue, 9 Dec 2008 18:59:10 -0700
References: <406131.67990.qm@web111406.mail.gq1.yahoo.com><F06289EF-B812-4197-863A-271292C3752F@vizachero.com><012c01c95a2a$a90d57c0$6400a8c0@Ken1><F79149D8-7C75-4287-9202-0A81B6ED5FC7@vizachero.com>


Most extinction probabilities are considered to be for some male that lived
at some moment in the tree; one forgets about his ancestry; he's assumed to
exist and one determines the chances his lineage will have not gone extinct
by G generations later, and the limit G = infinity can be considered. So at
any given time there are many lineages. They were produced in the past by
multiple offsprings of prior generation males. The past leading up to the
present is a given.

I suspect extinction of y lines in the post-industrial era societies may
still be above .5 in most such societies, but I am not sure.
I suspect extinction of y lines among L.D.S. males are below .5 over the
last 160 years.
But its an empirical question depending on human behavior and conditions.
In a model of males having 0,1,2 male offspring, p2 = 1/3, p1 = .5 and p0 =
1/6 would have extinction chance of .5. Tweak p2 up a bit at the expense of
p1 and you'd have extinction less than .5.

Somehow this thread slid from the issue of extinction down to one male line
to extinction of some male lines?


----- Original Message -----
From: "Vincent Vizachero" <>
To: <>
Sent: Tuesday, December 09, 2008 11:32 AM
Subject: Re: [DNA] Some thoughts about DNA survival


> New lineages can not be "produced", at least not by any definition I
> can conceive. Every man has a father, as we all know, and every
> woman has a mother. New lineages do not appear out of nowhere: the
> lineages in any given generation are simply a subset of those
> existing in the previous generation. Perhaps we have a definitional
> problem?
>
> If "most" men living, say, 500 years ago, have living y-line
> ancestors today then I'd be very surprised though I'll admit that my
> "most lineages go extinct" comment comes from a vague recollection.
> I would be interested in seeing the statement supported or
> contradicted, if you feel so inclined.
>
> Vince
>
>
>
> On Dec 9, 2008, at 1:19 PM, Ken Nordtvedt wrote:
>
>> I don't know about surnames, since they can perhaps not be
>> indefinately
>> created at a constant rate, but a sufficiently rapidly expanding male
>> population will not have "most" y lineages go extinct; or said
>> another way,
>> new ones will be produced by mutation faster than lines go extinct.
>
>
> -------------------------------
> To unsubscribe from the list, please send an email to
> with the word 'unsubscribe' without the
> quotes in the subject and the body of the message


This thread: