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Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 03, 2012 5:32 am
by Farpoint
E.P. Grondine wrote:Hi countrcultur -
No links, but i think if you search for Etruscan DNA you'll find them.
That would explain the strong "nasal" feature.
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 03, 2012 8:00 am
by E.P. Grondine
Hi farpoint -
I some cases, gross physical features, particularly height, are useful.
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 03, 2012 9:53 am
by Ernie L
speaking of nasal
anyone familiar with this blog....
http://s1.zetaboards.com/anthroscape/index/ ..I've only just started surfing some of the categories .
I'm sure I will learn a thing or two about the subject (DNA) once I stop gawking at the wreckage on the road side.
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 03, 2012 9:57 am
by uniface
countrcultur wrote:"Indigenous Amerindian genetic studies indicate that the "colonizing founders" of the Americas emerged from a single-source ancestral population that evolved in isolation, likely in Beringia."
Does that mean the dna is linked to asia or anywhere else? Is the DNA connected to anywhere else?
It means they're comparing the DNA of contemporary indigenous people here with the DNA contemporary people indigenous to Western Asia. Then transposing this, via a leap of faith, to the situation during the Pleistocene era.
Farpoint wrote:
of course European genetic influence started 400 years plus before this picture, none the less, they just don't look (metaphorically) Korean.
Edit: or 16000 years ago
NBBB
Farpoint wrote:Sinodonty . . . The strong nasal appearance
NB. Compare with the facial reconstruction of Kennewick Man.
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 03, 2012 12:19 pm
by Farpoint
uniface wrote:countrcultur wrote:"Indigenous Amerindian genetic studies indicate that the "colonizing founders" of the Americas emerged from a single-source ancestral population that evolved in isolation, likely in Beringia."
Does that mean the dna is linked to asia or anywhere else? Is the DNA connected to anywhere else?
It means they're comparing the DNA of contemporary indigenous people here with the DNA contemporary people indigenous to Western Asia. Then transposing this, via a leap of faith, to the situation during the Pleistocene era.
Farpoint wrote:
of course European genetic influence started 400 years plus before this picture, none the less, they just don't look (metaphorically) Korean.
Edit: or 16000 years ago
NBBB
Farpoint wrote:Sinodonty . . . The strong nasal appearance
NB. Compare with the facial reconstruction of Kennewick Man.
Ok, Uni, you got me, what does NBBB and NB mean?
As to Piccard, I am not impressed, artistic license.
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 03, 2012 5:04 pm
by uniface
Old school academic abbreviation. Like ibid(em), op(us) cit(atus) & that stuff.
NB = Nota bene ("Note well)
NBB = Note very well (This is really important - pay attention !)
NBBB is my own whimsy I suppose.
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 03, 2012 5:14 pm
by Farpoint
uniface wrote:Old school academic abbreviation. Like ibid(em), op(us) cit(atus) & that stuff.
NB = Nota bene ("Note well)
NBB = Note very well (This is really important - pay attention !)
NBBB is my own whimsy I suppose.
Ahhhh....
As to height, we have not discovered Homo floresiensis in the New World ........yet!
[fyi, I've finished R. Dennell's book and I am moving on to Gamble and Stringer.]
Re: But Still Clinging to the "Land Bridge"
Posted: Tue Oct 09, 2012 11:32 am
by Farpoint
Well, I find this interesting, though dated, from Stringer and Gamble, 1993, page 92:

Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 10, 2012 9:53 am
by E.P. Grondine
Hi farpoint -
The problem being that as that ratio is dependent on other factors than the temperature at the location of evolution, for now it is of limted use.
That said, some gross physical features can be of some use as they are preserved through changes in range.
Note well that any model that does not include impact among the factors affecting hominid evolution is useless.
To fruther complicate my earlier notes here on the pactical use of mt DNA...
From what I can make out, some mt DNA groups have been extincted from some of their ranges by impact, and are only recoverable from presserved remains.
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 10, 2012 4:09 pm
by Farpoint
"preserved remains"
Yeah, that would be nice!
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 10, 2012 5:44 pm
by E.P. Grondine
Hi Farpoint -
My own view is that DNA samples may be taken, the data extracted, and the sample reinterred along with the rest of the remains, but then I'm a raging moderate, and others, some of whom are responsible for the final decisions for their nations, hold other opinions.
I have not figured out how to extract/preserve data from skeletaal remains, but perhaps holography/3-D printing may be of use in this.
My view is that if some American archaeologists continue to try to ignore Native rights, it will only lead to more bad feelings.
Re: But Still Clinging to the "Land Bridge"
Posted: Thu Oct 18, 2012 8:07 pm
by Farpoint
Here we go with the genetics again:
MtDNA analysis of global populations
support that major population
expansions began before Neolithic Time
Americans.
For Native Americans, we observed six expansions of
lineages, of which four (A2, B2, C1 and D1) were shared by different
populations. The four lineages were also the main constitutions and
founding lineages in American gene pool30–32. The remaining 2
lineages, B2d and A2w were CLM-specific (see Figure 6). As
expected, we found some African L lineages and European N
lineages which might be admixed from recent contacts with
immigrants. For example, in MXL, African component (U6) was about
3% and European component (H, V and W) was about 12%
(Table S4), similar to the recent analysis in random Mexican sample
(3.1% and 13.6% respectively)33. To analyze the lineages autochthonous
to the New World, we focused on the classical Native
American haplogroups A2, B2, C1, D1 and D4h3, of which the
former 4 haplogroups showed star-like patterns. Time estimates
were generated according to different methods and rates (Table
S2), and the ages of 4 main clusters (A2, B2, C1 and D1) were
between the LGM and 13 kya. According to the previous model,
these lineages expanded rightly after the LGM via a coastal
(Pacific) route from Northern refuge (Beringia) towards the south.
The dispersal to the whole America continent was accomplished in a
very short time, probably in just several thousand years31,32,34–37.
The BSP plots (Figure 7B) including all Native American samples
also showed a huge expansion about 100 folds at 12 kya, which is
virtually identical to the former analysis38. In addition, all BSPs of
Americans (Figure 2 and 7B) showed recent bottlenecks, which
might be the impact of European contact39.
In Americas, agriculture originated independently in central
Mexico and Northern part of South America about 524 kya2, while
some researchers thought that the earliest agriculture could be traced
to Valdivia Valley in Chile , 6.4 kya15. Whenever the first farming occurred,
the expansions in America seemed have occurred much
earlier than the first appearance of agriculture.
What I wonder about is how well the genetics can be parsed to separate African and European gene flow from 16Kya or 500ya?
Re: But Still Clinging to the "Land Bridge"
Posted: Sat Oct 20, 2012 8:07 am
by E.P. Grondine
"The BSP plots (Figure 7B) including all Native American samples
also showed a huge expansion about 100 folds at 12 kya, which is
virtually identical to the former analysis38. In addition, all BSPs of
Americans (Figure 2 and 7B) showed recent bottlenecks, which
might be the impact of European contact39."
Like I said before, human evolution genetics its still a developing field.
This team is positing extinction by overhunting. The geological data shows extinction by
cometary impact, which likely explains the 100 fold expansion at 12 kya.
They noticed no ancient bottlenecks.
X mt DNA was ignored, and their samples for African were so small as to not be useful.
I suppose all we can do is to encourage them to continue to develop their techniques, in the hope that someday they may again come up with something as useful as mt DNA haplogroups.
https://www.youtube.com/watch?v=9BHvpWP2V9Y
Re: But Still Clinging to the "Land Bridge"
Posted: Wed Oct 24, 2012 6:00 am
by Farpoint
here is a paper that is pure data for background information on post LGM vegetation.
A GIS-based vegetation map of the world at the last glacial maximum (25,000–15,000 BP)
Ray and Adams 2001; see pdf page 39 for North America
Also, there are many "least cost" analysis of colonization paths into NA, beginning with Sauer in 1944, but I have not seen one starting from the East Coast.
Re: But Still Clinging to the "Land Bridge"
Posted: Tue Oct 30, 2012 3:53 pm
by countrcultur
Hey guys I need a bit of help. I need to know if my conclusions or statements in the following paragraph are accurate assessments of the quotes. This is for a paper so I don't want anyone to reword it for me or anything, i just want to know if i've made a proper interpretation of the quotes. For example, is the DNA evidence open-ended? Do the authors statements about their DNA findings defend the landbridge theory? Am I right that a bias exists that causes researchers to try and fit their findings into current theories? Any help appreciated.
In the study of the peopling of the Americas DNA evidence is seen to carry a lot of potential in helping to identify source populations and a timeline of migrations. There is still some work to do in this area as far as getting more of a sample size of indigenous DNA and the interpretation of the evidence is still biased towards the current scientific view or one or more migrations through beringia by an Asian population. It seems like a possible stretching to fit the theories as the evidence seems very open-ended. The study states that, “Phylogenetic analysis revealed that most Native American lineages are classified into four major distinct clusters. Individuals belonging to each cluster share at least two specific polymorphic sites that are nearly absent in other human populations, indicating a unique phylogenetic position of Native Americans.” They go on to say, “the four Native American clusters are distinct and dispersed in the tree. These clusters almost exclusively consist of Native Americans--with only a few Asians, if any.” The very small connection that can be made with a minute percentage of the DNA samples shouldn't be enough to point to all migrations coming from similar sources or even to all indigenous populations having originated from a set of recent migrations. While this article contains good information that is likely based on good science, the conclusions made seem to be a bit of a stretch and may possibly be attributed to a bias of conformity.