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 21 
 on: December 13, 2009, 02:55:07 PM 
Started by Charlie Hatchett - Last post by Charlie Hatchett
“…Our results show that genetic ancestry is strongly correlated with linguistic affiliations as well as geography.
Most populations show relatedness within ethnic/linguistic groups, despite prevalent gene flow among populations…”

“…More than 90% of East Asian (EA) haplotypes could be found in either Southeast Asian (SEA) or Central-South Asian (CSA) populations and show clinal structure with haplotype diversity decreasing from south to north. Furthermore, 50% of EA haplotypes were found in SEA only and 5% were found in CSA only, indicating that SEA was a major geographic source of EA populations…”

“…we concentrated on uncovering the geographic source(s) of EA and SEA populations…”

“…At K = 4, a component most frequently found in Negrito populations that is also shared by all SEA populations emerges, suggesting a common SEA ancestry…”

“…These observations suggest that SEA and EA populations share a common origin…”


“…The geographic source(s) contributing to EA
populations have long been debated. One hypothesis
suggests that all SEA and EA populations
derive primarily from a single initial migration,
which entered the continent along a southern,
largely coastal route (19, 20). Another hypothesis
argues for at least two independent migrations
into East Asia, first along a southern route, followed
later by a series of migrations along a more
northern route that served to bridge European and
EA populations, but with little contribution to
populations in Southeast Asia…”


“…The superior association between genetic
distance and the group indicator matrix as measured
by the correlation coefficients suggests that
prehistorical population divergence is the favored
model over IBD in explaining the data (24). This
conclusion is supported by simulation studies that
also suggest that the observed patterns cannot be
explained by simple IBD effects alone…”


“…The IBD model predicts a correlation of genetic
distance with geographical distance but not genetic
diversity and geographic distance (24). By
contrast, we found (Fig. 3A) that haplotype diversity
is strongly correlated with latitude (R2 =
0.91, P < 0.0001), with diversity decreasing from
south to north, which is consistent with a loss of
diversity as populations moved to higher latitudes.
In estimating the contribution of SEA and
Central-South Asian (CSA) haplotypes to the EA
gene pool by haplotype sharing analyses (16), we
found that more than 90% of haplotypes in EA
populations could be found in SEA and CSA populations,
of which about 50% were found in SEA
and EA only and 5% found in CSA only…”

“…Phylogenetic analysis of private
haplotypes indicates greater similarity between
EAand SEA populations relative to EA and
CSA populations (Fig. 3C). These observations
suggest that the geographic source(s) contributing
to EA populations were mainly from SEA populations,
with rather minor contributions from CSA
and that this clinal structure of EA populations
arose from prehistoric population divergence rather
than IBD or gene flow from CSA populations.…”


“…Our forward-time
simulation results under extreme ascertainment
scenarios (SOM text) show that the observed phylogeny
is not the result of ascertainment bias.
Simulation studies also suggest that substantial
levels of migration between populations after
their initial separation are unlikely to distort the
topology of the phylogeny…”

“…the evidence from our autosomal data
and the accompanying simulation studies (figs.
S29 and S30) point toward a history that unites the
Negrito and non-Negrito populations of Southeast
and East Asia via a single primary wave of entry
of humans into the continent…”

http://www.sciencemag.org/cgi/content/abstract/326/5959/1541

http://www.eurekalert.org/pub_releases/2009-12/afst-gah120909.php
_________________
Charlie Hatchett

PreClovis Artifacts from Central Texas
www.preclovis.com
http://forum.preclovis.com

 22 
 on: December 09, 2009, 10:53:23 PM 
Started by Robert Henvell - Last post by Robert Henvell
If anyone is interested in Tibet/China the following links provide access to numerous free PDF's.

  http://paleo.sscnet.ucla.edu/brantinghamPublications.htm

  http://www.anthro.ucdavis.edu/card/usprc/publications.htm

 23 
 on: December 08, 2009, 03:08:05 AM 
Started by trehinp - Last post by trehinp
Difficult to tell just from one picture...

It could well be that such hard stones were used by the palaeolithic human beings given that they were very hard and provided sharp cutting edges. But thia is pure spéculation...

Paul

 24 
 on: December 04, 2009, 11:19:26 AM 
Started by Jacques Cinq-Mars - Last post by E.P. Grondine
Just to end some confusion, Firestone et al's paper proposing two far earlier asteroid impacts (not YD comet impacts)
which occurred in Berringia may be found here:

http://ie.lbl.gov/mammoth/impact_old.html

Note that these are different than the YD comet impact ca. 13 kya. One of these asteroid impacts is hypothesized
at 35 kya, the other at 26 kya.


 25 
 on: December 01, 2009, 01:52:22 PM 
Started by trehinp - Last post by E.P. Grondine
http://www.rocksfromspace.org/December_1_2009.html

Thought you might enjoy this. Is that a core at the top right, a chopperto mid center, with a flaked piece to the left below it?

 26 
 on: November 16, 2009, 03:21:29 PM 
Started by E.P. Grondine - Last post by E.P. Grondine
http://www.sciencedaily.com/releases/2009/11/091111115843.htm

I myself would guess that the period around 50,000 BCE provided the environment in which the people
who later went to Pedra Furada, Brazil prospered.


 27 
 on: November 16, 2009, 02:32:39 PM 
Started by Jacques Cinq-Mars - Last post by E.P. Grondine
Links to Firestone's team's papers may be found here, alongside contact info:

http://ie.lbl. gov/mammoth/ mammoth.html Firestone paper links

 28 
 on: November 06, 2009, 12:50:40 PM 
Started by E.P. Grondine - Last post by E.P. Grondine
I will send any paleoanthropology participant who wants one a doc file of chapter 2 of my book, which covers
large impacts that occurred as man was evolving, and my estimate of their effects.

Simply PM me with your email address.

In your comments on it please remember that I was a space journalist, and not trained in this field.







 29 
 on: October 28, 2009, 12:59:05 PM 
Started by trehinp - Last post by trehinp
Just a quick message to apologize for being inactive on PALANTH for several month...

I've had some very serious health problems since February 2009, but things seem to be back to "normal"...

I have plenty of reading to do before I can again participate...

Yours very friendly.

Paul

 30 
 on: October 26, 2009, 10:54:20 PM 
Started by Charlie Hatchett - Last post by E.P. Grondine
Thanks for the news. 

It's good to see a frank discussion of taxa, and I expect that more will be held as more data is recovered.

In my opinion, one of the big problems the palaeoanthropology community is facing is exactly how to name a robust Erectus, as "Robustus" is already taken for a separate and extinct line. I went with Heidelbergensis at the time of my book, and took a lot of heat for it, even though I explained why in a footnote.

Once again, I'd suggest looking at the Zamanshin impact, 1 Mya,  as being the event which separated the common ancestral neanderthal/sapien.

If the data finally suggests a different date, then I'd suggest looking for another major comet or asteroid impact.

But then I've been wrong before, and I reserve the right to be wrong both now and in the future.

(Two major examples: one, never stumbling across the shiva impact when refuting Keller; two, ascribing the die off at 8,350 BCE to comet impact, when the impacts occurred ca. 10,900 BCE. And there were more...)

E.P. Grondine
Man and Impact in the Americas
(a pretty good book, really)

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