Spatial gradients in Clovis-age radiocarbon dates
Peter Alaca
Recently Jack Linthicum mentioned Hamilton & Buchanan
without giving a link or indication, and two days later
Daryl Krupa presented a link to the relevant article
in pdf format without mentioning title or authors, and
hardly an indication of what is in it. And I missed it.
Because I think the article is too important for such
poor exposure in this group, I again post a link to it
here in html, together with the abstract.
Hamilton, M.J & B. Buchanan (2007)
"Spatial gradients in Clovis-age radiocarbon dates
across North America suggest rapid colonization
from the north"
PNAS 104(40):15625-15630
http://www.pnas.org/cgi/content/full/104/40/15625
"A key issue in the debate over the initial
colonization of North America is whether
there are spatial gradients in the
distribution of the Clovis-age occupations
across the continent. Such gradients would
help indicate the timing, speed, and
direction of the colonization process.
In their recent reanalysis of Clovis-age
radiocarbon dates, Waters and Stafford
[Waters MR, Stafford TW, Jr (2007) Science
315:1122–1126] report that they find no
spatial patterning. Furthermore, they
suggest that the brevity of the Clovis time
period indicates that the Clovis culture
represents the diffusion of a technology
across a preexisting pre-Clovis population
rather than a population expansion.
In this article, we focus on two questions.
First, we ask whether there is spatial
patterning to the timing of Clovis-age
occupations and, second, whether the
observed speed of colonization is consistent
with demic processes.
With time-delayed wave-of-advance models, we
use the radiocarbon record to test several
alternative colonization hypotheses. We find
clear spatial gradients in the distribution
of these dates across North America, which
indicate a rapid wave of advance originating
from the north. We show that the high
velocity of this wave can be accounted for
by a combination of demographic processes,
habitat preferences, and mobility biases
across complex landscapes.
Our results suggest that the Clovis-age
archaeological record represents a rapid
demic colonization event originating from
the north."
--
p.a.
Jack Linthicum
> Recently Jack Linthicum mentioned Hamilton & Buchanan
> without giving a link or indication, and two days later
> Daryl Krupa presented a link to the relevant article
> in pdf format without mentioning title or authors, and
> hardly an indication of what is in it. And I missed it.
> Because I think the article is too important for such
> poor exposure in this group, I again post a link to it
> here in html, together with the abstract.
>
> Hamilton, M.J & B. Buchanan (2007)
> "Spatial gradients in Clovis-age radiocarbon dates
> across North America suggest rapid colonization
> from the north"
Sorry, I was following the format several use here, just give a title
and possibly a date and let the rest of the world worry about where to
find it. I would point out that some of the cites are available on-
line free for a limited period of time. Even my previous best source,
a local tech university, has taken to using on-line with a local id
for university use only in place of paper.
I do have a question on the sites chosen for this paper. They seem to
be rather selective and almost seem to be chosen for their ability to
add credence to a "from the North" thesis. I have heard and seen
references to many sites in the Chesapeake Bay area, part of the
Solutrean thesis, but I didn't see any in this paper.
The Royal Alberta Museum discusses the dichotomy of an area where you
would expect the older examples, the "Ice-Free Corridor", has,
instead, points that are 1500 years "younger" than those found in
areas to the South.
http://www.royalalbertamuseum.ca/human/archaeo/aspects/point.htm
Lee Olsen
> Recently Jack Linthicum mentioned Hamilton & Buchanan
> without giving a link or indication, and two days later
> Daryl Krupa presented a link to the relevant article
> in pdf format without mentioning title or authors, and
> hardly an indication of what is in it. And I missed it.
Yes, and before that:
From: Lee Olsen <paleoc...@hotmail.com> Newsgroups: sci.archaeology
Subject: Re: Pre-clovis Pacific coastal model - the devil is in the
details
Date: Wed, 14 May 2008 16:28:12 -0700 (PDT)
Message-ID: <131184e6-
ad0a-4925-880...@w8g2000prd.googlegroups.com>
Here is an online paper that gives the latest Waters and Stafford
(2007)
revised Clovis dates in both rcybp and calibrated (Table 1).
http://www.pnas.org/cgi/content/abstract/104/40/15625
> Because I think the article is too important for such
> poor exposure in this group,
A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
At this point, it was a side issue, so no particular comments were
made
about it.
Thanks for starting a new thread on this important topic. It is hard
to
cover every issue in every post without writing a book within each
post.
> I again post a link to it
> here in html, together with the abstract.
>
> Hamilton, M.J & B. Buchanan (2007)
> "Spatial gradients in Clovis-age radiocarbon dates
> across North America suggest rapid colonization
> from the north"
> PNAS 104(40):15625-15630http://www.pnas.org/cgi/content/full/104/40/15625
>
>
> Our results suggest that the Clovis-age
> archaeological record represents a rapid
> demic colonization event originating from
> the north."
So, who do you believe, a guy who has the reputation for owning one of
the
best 14C labs in the world, or someone who doesn't? I'm not taking
sides here,
just asking a question that needs to be pointed out.
>
> --
> p.a.
Lee Olsen
wrote:
>
> Sorry, I was following the format several use here, just give a title
> and possibly a date and let the rest of the world worry about where to
> find it.
From: Lee Olsen <paleoc...@hotmail.com> Newsgroups: sci.archaeology
Subject: Re: Pre-clovis Pacific coastal model - the devil is in the
details
Date: Wed, 14 May 2008 16:28:12 -0700 (PDT)
Message-ID: <131184e6-
ad0a-4925-880...@w8g2000prd.googlegroups.com>
Here is an online paper that gives the latest Waters and Stafford
(2007)
revised Clovis dates in both rcybp and calibrated (Table 1).
http://www.pnas.org/cgi/content/abstract/104/40/15625
A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
At that point, it was a SIDE issue, so no particular comments were
made
about Hamilton & Buchanan (2007).
Jack Linthicum
> On May 20, 4:17 am, Peter Alaca <p.al...@purple.invalid> wrote:
>
> > Recently Jack Linthicum mentioned Hamilton & Buchanan
> > without giving a link or indication, and two days later
> > Daryl Krupa presented a link to the relevant article
> > in pdf format without mentioning title or authors, and
> > hardly an indication of what is in it. And I missed it.
>
> Yes, and before that:
>
> From: Lee Olsen <paleoc...@hotmail.com> Newsgroups: sci.archaeology
> Subject: Re: Pre-clovis Pacific coastal model - the devil is in the
> details
> Date: Wed, 14 May 2008 16:28:12 -0700 (PDT)
> Message-ID: <131184e6-
> ad0a-4925-880c-1b5111142...@w8g2000prd.googlegroups.com>
>
> Here is an online paper that gives the latest Waters and Stafford
> (2007)
So, the sites and dates chosen are not subject to question?
Lee Olsen
wrote:
I posted a reference to H & B because it WAS online, Waters & Stafford
was not, unless one wanted to pay for it. At that point Daryl was
talking about a different issue, thus reference to Hamilton, M.J & B.
Buchanan (2007). The issue
at the time was not their conclusion but the use of "rcybp".
Jack Linthicum
So, the sites and dates chosen by Hamitlon and Buchanan are not
subject to question?
Lee Olsen
wrote:
> So, the sites and dates chosen by Hamitlon and Buchanan are not
> subject to question?
Who do you think is correct, Waters and Stafford who see no gradient
or
Hamilton & Buchanan who do?
Jack Linthicum
Can't answer the question? You are the supposed expert, which do you
prefer?
Lee Olsen
wrote:
> On May 20, 10:02 am, Lee Olsen <paleoc...@hotmail.com> wrote:
>
> > On May 20, 6:52 am, Jack Linthicum <jacklinthi...@earthlink.net>
> > wrote:
>
> > > So, the sites and dates chosen by Hamitlon and Buchanan are not
> > > subject to question?
>
> > Who do you think is correct, Waters and Stafford who see no gradient
> > or
> > Hamilton & Buchanan who do?
>
> Can't answer the question?
From above, " I'm not taking sides here, just asking a question that
needs to be pointed out."
>You are the supposed expert, which do you
> prefer?
Since the 14C experts disagree (Waters, Buchanan et al.), it looks
like there
are no experts so far. I think all the dating, in the Americas, should
be done over, not just a few of the Clovis dates as Waters and
Stafford have done. If they found errors in some of the redates, it
seems logical there are other errors out there to be fixed. Until that
happens, I think Buchanan and Waters *both* are just blowing smoke.
Peter Alaca
> On May 20, 7:17 am, Peter Alaca <p.al...@purple.invalid> wrote:
>> Recently Jack Linthicum mentioned Hamilton & Buchanan
>> without giving a link or indication, and two days later
>> Daryl Krupa presented a link to the relevant article
>> in pdf format without mentioning title or authors, and
>> hardly an indication of what is in it. And I missed it.
>> Because I think the article is too important for such
>> poor exposure in this group, I again post a link to it
>> here in html, together with the abstract.
>>
>> Hamilton, M.J & B. Buchanan (2007)
>> "Spatial gradients in Clovis-age radiocarbon dates
>> across North America suggest rapid colonization
>> from the north"
>> PNAS 104(40):15625-15630
>> http://www.pnas.org/cgi/content/full/104/40/15625
>
> Sorry, I was following the format several use here, just give a title
> and possibly a date and let the rest of the world worry about where to
> find it.
Please don't :-)
But is wasn't a personal reproach
> I would point out that some of the cites are available on-
> line free for a limited period of time. Even my previous best source,
> a local tech university, has taken to using on-line with a local id
> for university use only in place of paper.
Yes, that is a problem.
But sometimes it is woth to search further with
the titel. I often find the same article for free
on personal of institutional sites.
>
> I do have a question on the sites chosen for this paper. They seem to
> be rather selective and almost seem to be chosen for their ability to
> add credence to a "from the North" thesis. I have heard and seen
> references to many sites in the Chesapeake Bay area, part of the
> Solutrean thesis, but I didn't see any in this paper.
But they tested six potential origins, and
17 of the 23 used sites also are used by
Waters and Stafford (which used 30)
>
> The Royal Alberta Museum discusses the dichotomy of an area where you
> would expect the older examples, the "Ice-Free Corridor", has,
> instead, points that are 1500 years "younger" than those found in
> areas to the South.
>
> http://www.royalalbertamuseum.ca/human/archaeo/aspects/point.htm
I don't know where you read that.
That one(!) 'Braseth' point is an exception in
more than one respect.
--
p.a.
Peter Alaca
> On May 20, 4:17 am, Peter Alaca <p.al...@purple.invalid> wrote:
>> Recently Jack Linthicum mentioned Hamilton & Buchanan
>> without giving a link or indication, and two days later
>> Daryl Krupa presented a link to the relevant article
>> in pdf format without mentioning title or authors, and
>> hardly an indication of what is in it. And I missed it.
>
> Yes, and before that:
>
> From: Lee Olsen <paleoc...@hotmail.com> Newsgroups: sci.archaeology
> Subject: Re: Pre-clovis Pacific coastal model - the devil is in the
> details
> Date: Wed, 14 May 2008 16:28:12 -0700 (PDT)
> Message-ID: <131184e6-
> ad0a-4925-880...@w8g2000prd.googlegroups.com>
>
> Here is an online paper that gives the latest Waters and Stafford
> (2007)
> revised Clovis dates in both rcybp and calibrated (Table 1).
> http://www.pnas.org/cgi/content/abstract/104/40/15625
That's why I couldn't find what I though
I remebered: A link with the wrong authors.
>
>
>> Because I think the article is too important for such
>> poor exposure in this group,
>
> A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
I know that now, but because you linked to the abstract,
I didn't think of checking for free content. So why
didn't you link to the entire article with the same
summary at the top?
> At this point, it was a side issue, so no particular comments were
> made about it.
>
> Thanks for starting a new thread on this important topic. It is hard
> to cover every issue in every post without writing a book within each
> post.
>
>> I again post a link to it
>> here in html, together with the abstract.
>>
>> Hamilton, M.J & B. Buchanan (2007)
>> "Spatial gradients in Clovis-age radiocarbon dates
>> across North America suggest rapid colonization
>> from the north"
>> PNAS 104(40):15625-15630http://www.pnas.org/cgi/content/full/104/40/15625
>>
>
>> Our results suggest that the Clovis-age
>> archaeological record represents a rapid
>> demic colonization event originating from
>> the north."
> So, who do you believe, a guy who has the reputation for owning one of
> the best 14C labs in the world, or someone who doesn't? I'm not taking
> sides here, just asking a question that needs to be pointed out.
It is not about owning a 14c lab or not, but about
interpretation of the results.
H&M are using statistical methods, while W&S us 'simple'
chronological organisation of tha data.
At he moment I think that a north-eastern 'origin'
is the most likely.
--
p.a.
Jack Linthicum
"North-eastern"? I would assume either an inland move from the Pacific
(Western)or the "Ice Free Corridor" (Northern). I notice that the two
articles only share about 11 sites and dates, with another 10 or more
as "window-dressing".
Peter Alaca
I make that mistake often when talking about
America, never abot Europe. Of course I mean
North-western
"I would assume either an inland move from the Pacific
> (Western)or the "Ice Free Corridor" (Northern). I notice that the two
> articles only share about 11 sites and dates, with another 10 or more
> as "window-dressing".
No, as i wrote earlier, seventeen.
Lee Olsen
> Lee Olsen wrote, 20/05/2008 15:07:
>
>
>
>
>
> > On May 20, 4:17 am, Peter Alaca <p.al...@purple.invalid> wrote:
> >> Recently Jack Linthicum mentioned Hamilton & Buchanan
> >> without giving a link or indication, and two days later
> >> Daryl Krupa presented a link to the relevant article
> >> in pdf format without mentioning title or authors, and
> >> hardly an indication of what is in it. And I missed it.
>
> > Yes, and before that:
>
> > From: Lee Olsen <paleoc...@hotmail.com> Newsgroups: sci.archaeology
> > Subject: Re: Pre-clovis Pacific coastal model - the devil is in the
> > details
> > Date: Wed, 14 May 2008 16:28:12 -0700 (PDT)
> > Message-ID: <131184e6-
> > ad0a-4925-880c-1b5111142...@w8g2000prd.googlegroups.com>
>
> > Here is an online paper that gives the latest Waters and Stafford
> > (2007)
> > revised Clovis dates in both rcybp and calibrated (Table 1).
> >http://www.pnas.org/cgi/content/abstract/104/40/15625
>
> That's why I couldn't find what I though
> I remebered: A link with the wrong authors.
No link with the wrong authors was given by me.
The correct link to the data (table 1) was given.
Hamilton & Buchanan used Waters and Staffords
data and cited them in their paper.
>
>
>
> >> Because I think the article is too important for such
> >> poor exposure in this group,
>
> > A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
>
> I know that now, but because you linked to the abstract,
> I didn't think of checking for free content. So why
> didn't you link to the entire article with the same
> summary at the top?
I didn't have any trouble finding the paper on that page, why would
anyone else?
>
> > At this point, it was a side issue, so no particular comments were
> > made about it.
>
>
>
>
>
>
>
> > Thanks for starting a new thread on this important topic. It is hard
> > to cover every issue in every post without writing a book within each
> > post.
>
> >> I again post a link to it
> >> here in html, together with the abstract.
>
> >> Hamilton, M.J & B. Buchanan (2007)
> >> "Spatial gradients in Clovis-age radiocarbon dates
> >> across North America suggest rapid colonization
> >> from the north"
> >> PNAS 104(40):15625-15630http://www.pnas.org/cgi/content/full/104/40/15625
>
> >> Our results suggest that the Clovis-age
> >> archaeological record represents a rapid
> >> demic colonization event originating from
> >> the north."
> > So, who do you believe, a guy who has the reputation for owning one of
> > the best 14C labs in the world, or someone who doesn't? I'm not taking
> > sides here, just asking a question that needs to be pointed out.
>
> It is not about owning a 14c lab or not,
> but about
> interpretation of the results.
> H&M are using statistical methods,
Garbage in, garbage out.
> while W&S us 'simple'
> chronological organisation of tha data.
I'm sure Stafford is quite aware of the statictical methods involved.
Both used bogas data, so as I said in another post, both are
blowing smoke until ALL sites that have not been redated with
their newer methods are suspect.
>
> At he moment I think that a north-eastern 'origin'
> is the most likely.
Here is an opinion from a local Plateau archaeologist.
http://gsa.confex.com/gsa/2004AM/finalprogram/abstract_76927.htm
THE PALEOINDIAN COASTAL ENTRY HYPOTHESIS: A VIEW FROM THE COLUMBIA
PLATEAU, WASHINGTON STATE
Paper No. 85-1
"The “Clovis first” and “Ice Free Corridor” models of initial human
colonization of the Americas fail to accommodate the earliest
(Pre-11,000BP) Paleoindian archaeological sites. As a result the
Coastal Entry Hypothesis has recently gained rapid support among
Paleoindian specialists. While the details of coastal entry are sparse
due to an inundated Pleistocene coastline and low visibility of the
earliest sites, the unequivocal fact remains that at some point in
time the first Americans left the coast and entered the continental
interior. The most parsimonious explanation for interior colonization
from the coast would have colonizers moving through natural travel
corridors such as the Columbia River valley. Given its location
relative to receding continental glaciers, models of initial human
colonization along the Pacific coast should consider the Columbia
River corridor as a viable and likely initial pathway to the
continental interior. Geoarchaeological research at newly discovered
sites supports this hypothesis and clearly demonstrates that Upper
Pleistocene people exploited ecological zones of high productivity in
Scabland tracts of the Columbia Plateau. Along the Columbia River
corridor a generalized lack of Upper Pleistocene floodplain
development by and large precluded deposition and preservation of
Pleistocene archaeological sites; subsequent catastrophic flooding
likely destroyed any such evidence. To the contrary, upland sites in
Scabland tracts are well preserved and available to test hypotheses of
initial colonization. Geomorphic and hydrogeologic features that are
correlated with the earliest archaeological sites on the Columbia
Plateau include (1) catastrophic fluvial deposits adjacent to scoured
and denuded bedrock; (2) extinct paleolakes, marshes and remnant
landforms associated with high stands of these bodies of water; and
(3) alluvial terraces within scabland flood channels which formed as
the result of post-flood dewatering and subsequent upper Pleistocene
alluviation. By expanding research into the geologic and ecologic
context of the Cordilleran interior it is possible to hypothesize how
Pleistocene colonizers made the transition from marine to terrestrial
adapted life ways. This analysis of Columbia Plateau geoarchaeology is
an example of such research."
Peter Alaca
> Peter Alaca wrote:
>> Lee Olsen wrote
>>> Peter Alaca wrote:
>>>> Recently Jack Linthicum mentioned Hamilton & Buchanan
>>>> without giving a link or indication, and two days later
>>>> Daryl Krupa presented a link to the relevant article
>>>> in pdf format without mentioning title or authors, and
>>>> hardly an indication of what is in it. And I missed it.
>>> Yes, and before that:
>>> ------------
>>> From: Lee Olsen <paleoc...@hotmail.com> Newsgroups: sci.archaeology
>>> Subject: Re: Pre-clovis Pacific coastal model - the devil is in the
>>> details
>>> Date: Wed, 14 May 2008 16:28:12 -0700 (PDT)
>>> Message-ID: <131184e6-
>>> ad0a-4925-880c-1b5111142...@w8g2000prd.googlegroups.com>
>>> Here is an online paper that gives the latest Waters and Stafford
>>> (2007)
>>> revised Clovis dates in both rcybp and calibrated (Table 1).
>>> http://www.pnas.org/cgi/content/abstract/104/40/15625
>>> -------------
>> That's why I couldn't find what I though
>> I remebered: A link with the wrong authors.
>
> No link with the wrong authors was given by me.
Of course you did. You named Waters ans Stafford,
but the link was to Hamilton & Buchanan.
Confusing. That was why I couldn't find it.
> The correct link to the data (table 1) was given.
No, the link was to the abstract. No table in sight,
nor mentioned in the abstract.
> Hamilton & Buchanan used Waters and Staffords
> data and cited them in their paper.
>>>> Because I think the article is too important for such
>>>> poor exposure in this group,
>>> A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
>> I know that now, but because you linked to the abstract,
>> I didn't think of checking for free content. So why
>> didn't you link to the entire article with the same
>> summary at the top?
>
> I didn't have any trouble finding the paper on that page, why would
> anyone else?
Because you gave a link to an abstract, and free content
is not very common. So I didn't check.
With a link to the full paper, there wouldn't be
any misunderstanding possible.
Why do you think the data are bogus?
Do you "own one of the best 14c labs in the world"?
>> At he moment I think that a north-eastern 'origin'
>> is the most likely.
= north-western
> Here is an opinion from a local Plateau archaeologist.
> [...]
--
p.a.
Peter Alaca
> [...]
Well, that is like kicking in an open dooor, isn't it?
The artifacts show the use of rivervalleys (eg the Mackenzie)
But what has this to do with what you call "bogus'
14c dates?
--
p.a.
Daryl Krupa
> Jack Linthicum wrote, 20/05/2008 13:45:
> > The Royal Alberta Museum discusses the dichotomy of
> > an area where you would expect the older examples,
> > the "Ice-Free Corridor", has, instead, points that are
> > 1500 years "younger" than those found in areas to the South.
>
> >http://www.royalalbertamuseum.ca/human/archaeo/aspects/point.htm
>
> I don't know where you read that.
> That one(!) 'Braseth' point is an exception in
> more than one respect.
Indeed.
The history of Glacial Lake Peace is complex and
poorly-understood, but it would seem that during
the time that it covered Grande Prairie and Grovedale
that there was ice-free land to the west, north, and south.
I.e., there might well have been an "ice-free-corridor"
on the opposite side of G. L. Peace from
the Laurentide ice that was damming it.
The probl;em might be that the relevant earlier-available
ice-free and lake-free areas in western Alberta
have not been cleared for agriculture, and so
points have not been plowed up.
- Daryl Krupa
Jack Linthicum
From the cite
The oldest dated site in the vicinity, Charlie Lake Cave, has a fluted-
or basally thinned-point at about 10,500 years BP (Fladmark et al.
1988), but by this time fluted points had already enjoyed more than a
1,500 year tenure in the Great Plains (cf. Eighmy and LaBelle 1996). A
review of fluted point occurrences in Alberta (Gryba 1988) indicates
that the Peace River and Grande Prairie regions are well represented
by fluted points, apparently indicating an early resident population.
So far, however, all of these finds have originated from undated
surface contexts. If the Braseth point was found elsewhere on the
Great Plains, it could be expected to date anywhere from about 10,000
to over 11,000 years BP.
Lee Olsen
No, you are mistaken.
>You named Waters ans Stafford,
No, I said their data was in a table that could be found in an
online free paper, H & B (as a benefit to those who may have to pay
for the Waters and Stafford paper).
> but the link was to Hamilton & Buchanan.
Yes, there was a link on the page.
> Confusing. That was why I couldn't find it.
>
> > The correct link to the data (table 1) was given.
>
> No, the link was to the abstract. No table in sight,
Of course not, it was in the paper.
> nor mentioned in the abstract.
It wasn't in a lot of places.
>
> > Hamilton & Buchanan used Waters and Staffords
> > data and cited them in their paper.
> >>>> Because I think the article is too important for such
> >>>> poor exposure in this group,
> >>> A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
> >> I know that now, but because you linked to the abstract,
> >> I didn't think of checking for free content. So why
> >> didn't you link to the entire article with the same
> >> summary at the top?
>
> > I didn't have any trouble finding the paper on that page, why would
> > anyone else?
>
> Because you gave a link to an abstract, and free content
> is not very common.
How do you think I found the H&B paper?
>So I didn't check.
So you didn't check.
> With a link to the full paper, there wouldn't be
> any misunderstanding possible.
Yes there would.
Because they did not redate all of the old dates. If they found a few
old dates
wrong by checking a few sites with the latest tech, they have no idea
what other dates were wrong.
> Do you "own one of the best 14c labs in the world"?
Does H&B?
>
> >> At he moment I think that a north-eastern 'origin'
> >> is the most likely.
>
> = north-western
Confusing. That was why I couldn't find it.
Lee Olsen
How so?
> The artifacts show the use of rivervalleys (eg the Mackenzie)
What artifacts? Would you mind posting a live link to what you are
referring to?
>
> But what has this to do with what you call "bogus'
> 14c dates?
It doesn't, it has to do with:
"At he moment I think that a north-eastern 'origin' is the most
likely.
= north-western"
Peter Alaca
Yes
> I said their data was in a table that could be found in an
> online free paper, H & B (as a benefit to those who may have to pay
> for the Waters and Stafford paper).
>
>> but the link was to Hamilton & Buchanan.
>
> Yes, there was a link on the page.
Together with two different authors.
>> Confusing. That was why I couldn't find it.
>
>>> The correct link to the data (table 1) was given.
>> No, the link was to the abstract. No table in sight,
>
> Of course not, it was in the paper.
>> nor mentioned in the abstract.
>
> It wasn't in a lot of places.
>>> Hamilton & Buchanan used Waters and Staffords
>>> data and cited them in their paper.
>>>>>> Because I think the article is too important for such
>>>>>> poor exposure in this group,
>>>>> A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
>>>> I know that now, but because you linked to the abstract,
>>>> I didn't think of checking for free content. So why
>>>> didn't you link to the entire article with the same
>>>> summary at the top?
>>> I didn't have any trouble finding the paper on that page, why would
>>> anyone else?
>> Because you gave a link to an abstract, and free content
>> is not very common.
> How do you think I found the H&B paper?
I don't care how /you/ found it.
>
>> So I didn't check.
> So you didn't check.
That's what I say
>> With a link to the full paper, there wouldn't be
>> any misunderstanding possible.
> Yes there would.
No there wouldn't
You mentioned a table in a paper, but you linked
to an abstract without table.
That makes no sense as it was possible to link
to the full paper. And together with that 'wrong'
link, you mentioned the wrong authors.
I searched for your reference because I remembered
there was something like that, but I couldn't find
it because you did not mention the authors.
In the end (and too late) I found it with "pnas"
--
p.a.
Peter Alaca
The maps from the Paleoindian Database of the Americas, remember?
>
>> But what has this to do with what you call "bogus'
>> 14c dates?
>
> It doesn't, it has to do with:
>
> "At he moment I think that a north-eastern 'origin' is the most
> likely.
> = north-western"
so?
Lee Olsen
Which was explained.
>
>
>
>
>
> >> Confusing. That was why I couldn't find it.
>
> >>> The correct link to the data (table 1) was given.
> >> No, the link was to the abstract. No table in sight,
>
> > Of course not, it was in the paper.
> >> nor mentioned in the abstract.
>
> > It wasn't in a lot of places.
> >>> Hamilton & Buchanan used Waters and Staffords
> >>> data and cited them in their paper.
> >>>>>> Because I think the article is too important for such
> >>>>>> poor exposure in this group,
> >>>>> A *LIVE LINK* to the *ENTIRE* article was on the page I posted.
> >>>> I know that now, but because you linked to the abstract,
> >>>> I didn't think of checking for free content. So why
> >>>> didn't you link to the entire article with the same
> >>>> summary at the top?
> >>> I didn't have any trouble finding the paper on that page, why would
> >>> anyone else?
> >> Because you gave a link to an abstract, and free content
> >> is not very common.
> > How do you think I found the H&B paper?
>
> I don't care how /you/ found it.
And I don't care what is confusing to you, Mr. north-eastern 'origin'
= north-western.
>
>
>
> >> So I didn't check.
> > So you didn't check.
>
> That's what I say
Yes, we know what your failings are.
>
> >> With a link to the full paper, there wouldn't be
> >> any misunderstanding possible.
> > Yes there would.
>
> No there wouldn't
>
> You mentioned a table in a paper, but you linked
> to an abstract without table.
I know, I didn't claim the table was in the abstract.
> That makes no sense as it was possible to link
> to the full paper. And together with that 'wrong'
> link, you mentioned the wrong authors.
No, I mentioned the correct paper and the link was
clearly on the page for those not helpless.
>
> I searched for your reference because I remembered
> there was something like that, but I couldn't find
> it because you did not mention the authors.
> In the end (and too late) I found it with "pnas"
Nobody cares what you searched for and failed to find.
Lee Olsen
What about the maps?
>
>
>
> >> But what has this to do with what you call "bogus'
> >> 14c dates?
>
> > It doesn't, it has to do with:
>
> > "At he moment I think that a north-eastern 'origin' is the most
> > likely.
> > = north-western"
>
> so?
So?
Peter Alaca
You are the on that failed.
>
>
>>>> With a link to the full paper, there wouldn't be
>>>> any misunderstanding possible.
>>> Yes there would.
>> No there wouldn't
>>
>> You mentioned a table in a paper, but you linked
>> to an abstract without table.
>
> I know, I didn't claim the table was in the abstract.
>
>> That makes no sense as it was possible to link
>> to the full paper. And together with that 'wrong'
>> link, you mentioned the wrong authors.
>
> No, I mentioned the correct paper and the link was
> clearly on the page for those not helpless.
>
>
>> I searched for your reference because I remembered
>> there was something like that, but I couldn't find
>> it because you did not mention the authors.
>> In the end (and too late) I found it with "pnas"
>
> Nobody cares what you searched for and failed to find.
In that case there is no need for you to give references.
Is it that difficult for you to say: "Yes, my reference
was confusing" instead of blaming others for it?
--
p.a.
Peter Alaca
Read what I wrote
Daryl Krupa
Peter Alaca
> Some more info:
>
> http://cgrg.geog.uvic.ca/abstracts/Young~AA.html
Since the purported "Ice-Free Corridor"
has been demonstrated to have been full of
ice during glacial maximum, it becomes
crucial to refine the deglacial chronology
to see if the interior route was a tenable
option for migration of the first peoples
into the Americas.
I am surpised, because every map I know
shows the 'corridor'
>
> http://preview.tinyurl.com/66tp9d
Nothing to view
Lee Olsen
>
> You are the on that failed.
Only in your imagination.
>
> Is it that difficult for you to say: "Yes, my reference
> was confusing" instead of blaming others for it?
You need to spend more time on learning to read.
Lee Olsen
> >> The maps from the Paleoindian Database of the Americas, remember?
>
> > What about the maps?
>
> Read what I wrote
What about what you wrote? Did you have a point?
Daryl Krupa
> Daryl Krupa wrote, 22/05/2008 00:44:
>
> > Some more info:
>
> >http://cgrg.geog.uvic.ca/abstracts/Young~AA.html
>
> Since the purported "Ice-Free Corridor"
> has been demonstrated to have been full of
> ice during glacial maximum, it becomes
> crucial to refine the deglacial chronology
> to see if the interior route was a tenable
> option for migration of the first peoples
> into the Americas.
>
> I am surpised, because every map I know
> shows the 'corridor'
Then look at these, Peter:
http://www.qpg.geog.cam.ac.uk/lgmextent.html
http://www.cabrillo.edu/~crsmith/glacloop.gif
http://www.worldclimatereport.com/wp-images/iceage2.JPG
http://earthguide.ucsd.edu/images/aldemo/glossary/NAL2215s.gif
http://content.answers.com/main/content/wp/en/thumb/0/04/180px-Pleistocene_north_ice_map.jpg
http://epswww.unm.edu/facstaff/gmeyer/eps481/images/climap.gif
http://www.nature.com/nature/journal/v402/n6757/fig_tab/402063a0_F1.html
http://www.ncdc.noaa.gov/paleo/image/laurentide.gif
http://www.bio.umass.edu/biology/conn.river/misc_images/laurentide.jpg
Etc., etc., etc..
- Daryl Krupa
Peter Alaca
> On May 21, 4:59 pm, Peter Alaca <p.al...@purple.invalid> wrote:
>> Daryl Krupa wrote, 22/05/2008 00:44:
>>
>>> Some more info:
>>> http://cgrg.geog.uvic.ca/abstracts/Young~AA.html
>> Since the purported "Ice-Free Corridor"
>> has been demonstrated to have been full of
>> ice during glacial maximum, it becomes
>> crucial to refine the deglacial chronology
>> to see if the interior route was a tenable
>> option for migration of the first peoples
>> into the Americas.
>>
>> I am surpised, because every map I know
>> shows the 'corridor'
>
> Then look at these, Peter:
>
> http://www.qpg.geog.cam.ac.uk/lgmextent.html
Too small
>
> http://www.cabrillo.edu/~crsmith/glacloop.gif
Too small
>
> http://www.hi.is/~oi/LGM.jpg
Shows a corridor
>
> http://www.worldclimatereport.com/wp-images/iceage2.JPG
What are the numbers, stages? Age?
Then there is a corridor at 14.
>
> http://earthguide.ucsd.edu/images/aldemo/glossary/NAL2215s.gif
Too small
>
> http://content.answers.com/main/content/wp/en/thumb/0/04/180px-Pleistocene_north_ice_map.jpg
Ice free mountians?
> http://epswww.unm.edu/facstaff/gmeyer/eps481/images/climap.gif
Too small
>
> http://www.nature.com/nature/journal/v402/n6757/fig_tab/402063a0_F1.html
Nice maps.
If I understand this correctly, the white area
is during LGM and the yellow 8000-9500
>
> http://www.ncdc.noaa.gov/paleo/image/laurentide.gif
> http://www.bio.umass.edu/biology/conn.river/misc_images/laurentide.jpg
Not sure about this. At least there is a partial gap
>
> Etc., etc., etc..
>
> - Daryl Krupa
I see that the 'gap' between the Cordilleran and Laurentide
ice sheet was never closed over the full length.
Is it possible that it was never realy closed?
And if it was, I suppose that is was open early.
(not necessarily accesable)
--
p.a.
Daryl Krupa
> Daryl Krupa wrote, 23/05/2008 00:52 (minus un-marked snips):
<snip>
Peter:
If you mean the yellow line east of the B.C. coast,
that indicates a subduction zone, subsurface.
> >http://www.worldclimatereport.com/wp-images/iceage2.JPG
>
> What are the numbers, stages? Age?
> Then there is a corridor at 14.
Yes, those are numbers ka, but
14 ka is not LGM, 21-17 ka is LGM.
> >http://content.answers.com/main/content/wp/en/thumb/0/04/180px-Pleist...
>
> Ice free mountians?
Not that I can see ...
> >http://www.nature.com/nature/journal/v402/n6757/fig_tab/402063a0_F1.html
>
> Nice maps.
> If I understand this correctly, the white area
> is during LGM and the yellow 8000-9500
Yes.
> >http://www.bio.umass.edu/biology/conn.river/misc_images/laurentide.jpg
>
> Not sure about this. At least there is a partial gap
Not really; the line across the "t" in
"Cordilleran Ice Sheet" marks the conjunction of
the CIS and the Laurentide Ice Sheet.
At the southern end of the merging zone
you can see by the flow-line arrows that
flow of each ice sheet was deflected south by the other.
> I see that the 'gap' between the Cordilleran and Laurentide
> ice sheet was never closed over the full length.
I can't imagine how you would arrive at that impression.
> Is it possible that it was never realy closed?
Not at the LGM; cosmic-ray dating of erratic boulders
brought south by the coalescent southward flow mentioned above
shows that they were deposited around the time of the LGM.
> And if it was, I suppose that is was open early.
If by"early" you mean about 14 ka, then yes that may be so,
but Young and Rains suggest that there is evidence that
the separation might have been later than that, or at least that the
LIS retreated later than that.
> (not necessarily accesable)
Yep; it takes time to establish vegetation next to continental
ice sheets. The likeliest early route would have been
west of the western margin of the LIS, because it seems
(even without Young's and Rains' assertion) that
the CIS retreated earlier than the LIS.
I'll have to talk to Bruce Rains about this one.
He's no flake, and I trust his caution and professional judgement.
This new info will have a significant effect upon the
Clovis-migration-from-the-north discussions.
- Daryl Krupa
Jack Linthicum
I see the very best case still talks about mile high walls on each
side of the tundra corridor.
The Human Story: Our History, from the Stone Age to Today
By James C. Davis
http://books.google.com/books?id=vFIbccsnb4UC&pg=PA8&lpg=PA8&dq=ice+free+corridor+mile+high&source=web&ots=7oVf1jMzhg&sig=F0axcLq6MPRaB4FHm5zHR8UkM1k&hl=en
page 8
Peter Alaca
> On May 22, 5:22 pm, Peter Alaca <p.al...@purple.invalid> wrote:
>> Daryl Krupa wrote, 23/05/2008 00:52 (minus un-marked snips):
> <snip>
>>> http://www.hi.is/~oi/LGM.jpg
>> Shows a corridor
>
> Peter:
> If you mean the yellow line east of the B.C. coast,
> that indicates a subduction zone, subsurface.
>
>>> http://www.worldclimatereport.com/wp-images/iceage2.JPG
>> What are the numbers, stages? Age?
>> Then there is a corridor at 14.
>
> Yes, those are numbers ka, but
> 14 ka is not LGM, 21-17 ka is LGM.
>
>>> http://content.answers.com/main/content/wp/en/thumb/0/04/180px-Pleist...
>> Ice free mountians?
>
> Not that I can see ...
I see something free of ice.
>
>>> http://www.nature.com/nature/journal/v402/n6757/fig_tab/402063a0_F1.html
>> Nice maps.
>> If I understand this correctly, the white area
>> is during LGM and the yellow 8000-9500
>
> Yes.
>
>>> http://www.bio.umass.edu/biology/conn.river/misc_images/laurentide.jpg
>> Not sure about this. At least there is a partial gap
>
> Not really; the line across the "t" in
> "Cordilleran Ice Sheet" marks the conjunction of
> the CIS and the Laurentide Ice Sheet.
> At the southern end of the merging zone
> you can see by the flow-line arrows that
> flow of each ice sheet was deflected south by the other.
Yes, but it also means that they did not act
as one sheet
>
>> I see that the 'gap' between the Cordilleran and Laurentide
>> ice sheet was never closed over the full length.
>
> I can't imagine how you would arrive at that impression.
In the north and south are indentations marking
the division between the sheets. The one in the north
is pretty long. (sorry for my inability of using
geographical names)
>
>> Is it possible that it was never realy closed?
>
> Not at the LGM; cosmic-ray dating of erratic boulders
> brought south by the coalescent southward flow mentioned above
> shows that they were deposited around the time of the LGM.
Is there geological (sedimentairy) evidence that
they ever actually touched?
>> And if it was, I suppose that is was open early.
>
> If by"early" you mean about 14 ka, then yes that may be so,
> but Young and Rains suggest that there is evidence that
> the separation might have been later than that, or at least that the
> LIS retreated later than that.
Before LGM they were seperated.
>> (not necessarily accesable)
> Yep; it takes time to establish vegetation next to continental
> ice sheets.
If you like fish, vegetation is not really necessary.
> The likeliest early route would have been
> west of the western margin of the LIS, because it seems
> (even without Young's and Rains' assertion) that
> the CIS retreated earlier than the LIS.
>
> I'll have to talk to Bruce Rains about this one.
> He's no flake, and I trust his caution and professional judgement.
> This new info will have a significant effect upon the
> Clovis-migration-from-the-north discussions.
The question is why they would come from the north
between the sheets when the coastal route seems much
more attractive.
--
p.a.
Jack Linthicum
They were already inland. The Mesa, Nenana and Engigstciak sites for
example.
http://instaar.colorado.edu/meetings/AW2006/abstract_detail.php?abstract_id=86
Further to the north, a small cultural component at Bluefish Caves in
the Yukon, has been dated by Cinq-Mars at ca. 13,000 BP.
http://www.nps.gov/akso/akarc/early.htm
Probably two cultures, the land large animal hunting walking group and
the sea marine life hunting marinecraft group.
Peter Alaca
But how did they arrive there?
It is not possible that "They were already inland"
> Probably two cultures, the land large animal hunting walking group and
> the sea marine life hunting marinecraft group.
--
p.a.
Daryl Krupa
On May 23, 5:17 pm, Jack Linthicum <jacklinthi...@earthlink.net>
wrote:
> I see the very best case still talks about mile high walls on each
> side of the tundra corridor.
>
> The Human Story: Our History, from the Stone Age to Today
> page 8
I saw no way to look at page 8 at that site, but
I think I finally found an excerpt with a relevant quotation.
From:
http://www.ereader.com/servlet/mw?t=book_excerpt&bookid=25294&si=59
"
Or they could have trod a narrow ice-free corridor
that we know led south between the glaciers.
As they trudged along this corridor
mile-high walls of ice would have flanked them on both sides.
"
That's crap.
Yes, there may have been ice a mile thick on each side, but
the nearest ice would have been much, much thinner, and
one would have to travel a great distance toward the centre of
an ice sheet to stand upon ice a mile thick.
Ice is not strong enough to form mile-high walls.
Ice flows under its own weight when it gets
more than 10 metres thick.
Unless it is melting very, very rapidly,
the edge of a continental glacier is at least 50 miles
from a point where it might be a mile mile.
A more common surface gradient is one mile of height
for every 300 miles of distance from the edge.
If there could be mile-high walls of ice along
an ice-free corridor in North America then we would see
mile-high walls of ice at the edges of the Greenland and
Antarctic ice sheets today, and we would be dodging
icebergs more than 600 feet high in the North Atlantic
and Southern Oceans.
I.e., icebergs five times as high as the top of the QEII.
The ice on either side of such a corridor would have been
a mile high like the Rocky Mountains are two-mile-high walls
beside the Pacific Ocean, or like the Alps and the Caucasus
Mountains are mile-high walls beside the Bosphorus.
Or like the Rockies and the Appalachians are mile-high walls
beside the Mississippi River.
Or like the Laurentian and the Appalachian Mountains
beside the St. Lawrence River.
That author has nothing useful to tell you about
glacial environments.
That passage is nothing at all like
"the very best case".
That passage is stupid.
Ignore that book.
- Daryl Krupa
Daryl Krupa
> Daryl Krupa wrote, 24/05/2008 00:59:
<snip>
> >>>http://content.answers.com/main/content/wp/en/thumb/0/04/180px-Pleist...
> >> Ice free mountians?
> > Not that I can see ...
> I see something free of ice.
Yes, of course, but are they mountains?
Which mountains are they, please?
<snip>
> >>>http://www.bio.umass.edu/biology/conn.river/misc_images/laurentide.jpg
> >> Not sure about this. At least there is a partial gap
>
> > Not really; the line across the "t" in
> > "Cordilleran Ice Sheet" marks the conjunction of
> > the CIS and the Laurentide Ice Sheet.
> > At the southern end of the merging zone
> > you can see by the flow-line arrows that
> > flow of each ice sheet was deflected south by the other.
>
> Yes, but it also means that they did not act
> as one sheet
So what?
Two people doing the tango don't act as one body, but
that doesn't mean that you can just blithely walk between them
to get to the punch bowl ...
Colliding Sumo wrestlers don't act as one body, but
that doesn't mean that you can walk between them
at the moment of impact ...
The American and Soviet armies did not act as one body, but
but once they met in Germany in 1945, there was no chance of
German forces passing along the line between their respective
zones of control ...
The CIS and LIS met and deflected each other southward for
hundreds of kilometres, from Jasper National Park to the
U.S. border.
After they became confluent, ice on both sides of the suture
was about a mile thick, and moved in the same direction.
Actually, in the confluence zone, they did act as one body,
moving south-southeast along the Foothills of the Rocky Mountains.
And north of Jasper National Park, they probably just met and
flowed not at all, except to one side or the other.
There was no ice-free corridor
on the east side of the Rocky Mountains
at Last Glacial Maximum.
Accept it, and move on.
> >> I see that the 'gap' between the Cordilleran and Laurentide
> >> ice sheet was never closed over the full length.
>
> > I can't imagine how you would arrive at that impression.
>
> In the north and south are indentations marking
> the division between the sheets. The one in the north
> is pretty long. (sorry for my inability of using
> geographical names)
But that is not an "ice-free corridor".
At best, it is an "ice-free vestibule"
at each end of a contiguous suture zone.
> >> Is it possible that it was never realy closed?
>
> > Not at the LGM; cosmic-ray dating of erratic boulders
> > brought south by the coalescent southward flow mentioned above
> > shows that they were deposited around the time of the LGM.
>
> Is there geological (sedimentairy) evidence that
> they ever actually touched?
YES! I JUST TOLD YOU!
> >> And if it was, I suppose that is was open early.
>
> > If by"early" you mean about 14 ka, then yes that may be so,
> > but Young and Rains suggest that there is evidence that
> > the separation might have been later than that, or at least that the
> > LIS retreated later than that.
>
> Before LGM they were seperated.
So What?
You were talking about LGM, not "before LGM".
> >> (not necessarily accesable)
> > Yep; it takes time to establish vegetation next to continental
> > ice sheets.
>
> If you like fish, vegetation is not really necessary.
It takes time to establish an environment that will support
the food that fish eat.
That means vegetation.
> > The likeliest early route would have been
> > west of the western margin of the LIS, because it seems
> > (even without Young's and Rains' assertion) that
> > the CIS retreated earlier than the LIS.
>
> > I'll have to talk to Bruce Rains about this one.
> > He's no flake, and I trust his caution and professional judgement.
> > This new info will have a significant effect upon the
> > Clovis-migration-from-the-north discussions.
>
> The question is why they would come from the north
> between the sheets when the coastal route seems much
> more attractive.
Well, that's an entirely new question.
I believe that I have shown that your earlier apprehension of
common graphic evidence of an LGM ice-free corridor was mistaken.
- Daryl Krupa
Peter Alaca
> On May 24, 3:55 am, Peter Alaca <p.al...@purple.invalid> wrote:
>> Daryl Krupa wrote, 24/05/2008 00:59:
> <snip>
>>>>> http://content.answers.com/main/content/wp/en/thumb/0/04/180px-Pleist...
>>>> Ice free mountians?
>>> Not that I can see ...
>> I see something free of ice.
>
> Yes, of course, but are they mountains?
> Which mountains are they, please?
You tell me. I live in Europe
It only try to learn from you, Daryl.
It has nothing to do with accepting or not
>>>> I see that the 'gap' between the Cordilleran and Laurentide
>>>> ice sheet was never closed over the full length.
>>> I can't imagine how you would arrive at that impression.
>> In the north and south are indentations marking
>> the division between the sheets. The one in the north
>> is pretty long. (sorry for my inability of using
>> geographical names)
>
> But that is not an "ice-free corridor".
> At best, it is an "ice-free vestibule"
> at each end of a contiguous suture zone.
Yes, on the small maps I have seen.
I only wondered if that means that
your 'vestibues were' connected.
>
>>>> Is it possible that it was never realy closed?
>>> Not at the LGM; cosmic-ray dating of erratic boulders
>>> brought south by the coalescent southward flow mentioned above
>>> shows that they were deposited around the time of the LGM.
>> Is there geological (sedimentairy) evidence that
>> they ever actually touched?
>
> YES! I JUST TOLD YOU!
That is not how I read it.
Does the fact that the boulders flowed together
means that the ice sheets touched? Were they
transported by ice or by water?
>
>>>> And if it was, I suppose that is was open early.
>>> If by"early" you mean about 14 ka, then yes that may be so,
>>> but Young and Rains suggest that there is evidence that
>>> the separation might have been later than that, or at least that the
>>> LIS retreated later than that.
>> Before LGM they were seperated.
>
> So What?
> You were talking about LGM, not "before LGM".
We are talking about the possibility
of 'migrating' people from Azia.
Before, during or after LGM.
>
>>>> (not necessarily accesable)
>>> Yep; it takes time to establish vegetation next to continental
>>> ice sheets.
>> If you like fish, vegetation is not really necessary.
>
> It takes time to establish an environment that will support
> the food that fish eat.
> That means vegetation.
Spawning Salmon etc?
>
>> > The likeliest early route would have been
>>> west of the western margin of the LIS, because it seems
>>> (even without Young's and Rains' assertion) that
>>> the CIS retreated earlier than the LIS.
>>> I'll have to talk to Bruce Rains about this one.
>>> He's no flake, and I trust his caution and professional judgement.
>>> This new info will have a significant effect upon the
>>> Clovis-migration-from-the-north discussions.
>> The question is why they would come from the north
>> between the sheets when the coastal route seems much
>> more attractive.
>
> Well, that's an entirely new question.
> I believe that I have shown that your earlier apprehension of
> common graphic evidence of an LGM ice-free corridor was mistaken.
That is (still) a common view. I said above
that it is not the most likely route.
And I don't really care how they came to America.
More interesting is the question where they came
from and when, and whether archaeological datings
can be used to answer that questions.
--
p.a.
Jack Linthicum
Try using the up button on the right,
Daryl Krupa
wrote:
<snip>
> Try using the up button on the right,
I have no idea what you are talking about.
- Daryl Krupa
Daryl Krupa
<snip>
> Does the fact that the boulders flowed together
> means that the ice sheets touched? Were they
> transported by ice or by water?
http://www3.telus.net/lejgeology/etrain/
<snip>
> > You were talking about LGM, not "before LGM".
>
> We are talking about the possibility
> of 'migrating' people from Azia.
> Before, during or after LGM.
This is what you were talking about:
<BEGIN QUOTE>
Daryl Krupa wrote, 22/05/2008 00:44:
> Some more info:
> http://cgrg.geog.uvic.ca/abstracts/Young~AA.html
Since the purported "Ice-Free Corridor"
has been demonstrated to have been full of
ice during glacial maximum, it becomes
crucial to refine the deglacial chronology
to see if the interior route was a tenable
option for migration of the first peoples
into the Americas.
I am surpised, because every map I know
shows the 'corridor'
<END QUOTE>
I supplied a quote from Young and Rains about
the demonstrable lack of existence of
an "Ice-Free Corridor" "during glacial maximum".
You then opined that
an "Ice-Free Corridor" "during glacial maximum"
Was shown on every map you knew.
You said nothing about "Before, during or after LGM."
I've had enough.