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Power77
18-09-14, 01:26
There is much debate in the scientific community about the peopling of the Americas. Most of the oldest skulls in the Americas appear somewhat divergent from the traditional phenotype. We can mention Luzia in Brazil(allegedly Australoid), Kennewick Man in Washinghton State(allegedly Europoid or Ainuid) and Penon Woman in Mexico(allegedly Europoid). Then there is the whole question of the Solutrean Hypothesis due to similarities between spears of Europe and North America of the same period. But some studies have largely disproved such an hypothesis. There is much variety among the indigenous peoples of the Americas in terms of phenotype. Some can appear somewhat Europoid(Plains Indians) while others can appear full blown Mongoloid(Eskimos/Inuits and some Amazonian tribes). Others have somewhat of an unclassifiable phenotype(Andeans and some Central Americans). Pretty much all Amerindians from North to South America carry the Q1a3* lineage(specifically M3) in a rather homogenous manner. While the mtDNA looks somewhat more diverse but still appears to come from only 4 women(A, B, C and D). Then there is the fact that mtDNA X is found in some North American tribes as well as controversial R1* lineages which seem to overlap heavily with mtDNA X in distribution. I was thinking about 25 000 years-old Malta boy in Siberia who seems to have carried Y-chromosome R* and mtDNA U. Maybe a related population was more widespread in the Americas during a certain period which may explain the Solutrean-like Clovis artifacts, Kennewick Man and these West Eurasian lineages in North America. For that reason, I suspect the possibility of finding more pre-Columbian Caucasoid mtDNA such as U or H among North American Indians. The problem is that most Native American tribes seem thoughly opposed to DNA testing on both living people of their community as well as ancient remains they argue to be their ancestors( see Kennewick Man controversy). So that may complicate an accurate genetic profile of both the peopling of the Americas and modern Amerindians. What do you people on this forum think? Share.

bicicleur
18-09-14, 20:51
The problem is that most Native American tribes seem thoughly opposed to DNA testing on both living people of their community as well as ancient remains they argue to be their ancestors( see Kennewick Man controversy)

R in North America, is it R* or R1* or R1a or R1b ?

It's a simple question which would explain a lot but nobody seems to know the answer.

Power77
18-09-14, 21:07
@bicicleur So Amerindians can't have any pre-Columbian R1* lineages according to you? Even if these R1*'s appear to be R1a* or R1b* it would not necessary mean that they are post-1492 European clades at all!

bicicleur
18-09-14, 22:44
@bicicleur So Amerindians can't have any pre-Columbian R1* lineages according to you? Even if these R1*'s appear to be R1a* or R1b* it would not necessary mean that they are post-1492 European clades at all!

i don't think you know my opinion re pre-columbian R

Power77
18-09-14, 23:44
@bicicleur So what are your opinions on it then?

bicicleur
18-09-14, 23:47
i think most northamerican R is precolumbian
there is simply to much of them, and if they were European, there should be I as well
if it would appear they are all R1a/R1b i'd probably change my mind

Power77
19-09-14, 03:03
@bicicleur OK. I personally believe that many Amerindian lineages went extint either because of the diseases brought by the Europeans post-1492 or of the explosion of Q1a* and R1* Y-chromosomes in the Americas during antiquity or even prehistory replacing these hypothetical extinct lineages. There could even have been Y-haplogroup D* in the New World which for some reason went extinct there or got preserved in very isolated tribes not genetically tested yet. Such an haplogroup may have been the main lineage of Luzia's Australoid people in Brazil for instance. Also it may explain the disparities between M-descended mtDNA(D1,D4h3,C1) and N+R-descended mtDNA(A2,B2,X2 and potentially H and U) in the continent. Amerindian M-descended mtDNA lineages (who may be the true first Americans) could have colonised the continent with Y-haplogroup D* as a partner. Then later (perhaps with Clovis culture) another wave associated with N and R-descended mtDNA and Y-haplogroups Q1a* and maybe R1* settled en masse the New World,killed the D* males and took their wives. Q1a* would have become the dominant male haplogroup in the entire Americas while R1* just got isolated to eastern North America. Such a scenario would have therefore given rise to Modern American Indians as we know them. What do you think of this theory?

bicicleur
19-09-14, 08:46
The model I have in mind is first a 16000 year old coastal immigration of Q1a-M3, followed by the 13000 year old immigration between Cordillera and Laurentide ice sheets of 2 tribes :
Q1a-Z780 east of the Missisipi, which were the Clovis people and R1 west of the Missisipi - Algonquin. The C Na Dene tribe would have seeped in from Alaska when the Cordillera ice sheet melted further. Later came 2 waves of Eskimos, both Q of which the first wave went extinct.

When do you think haplo D arrived, 16000 years ago, or before the ice age?
Haplo D were coastal tribes.
D1 moved north along to coast to split at the Yangzi river mouth, 1 part going inland along the Yangzi and another part arriving in Japan some 20.000 years ago

Power77
19-09-14, 16:45
@bicicleur I think D* could have reached the Americas between 25 000 to 20 000 years ago. I even believe that poorly studied isolated Amerindians such as Baja California natives and Fuegians likely would have carried majority (if not exclusively)Y-haplogroup D* till the modern era. It is worth mentionning that ancient DNA from Fuegian remains yields only M-descended mtDNA(D1,D4h3 and C1) unlike their more northernly neighbours. Then again this is only mtDNA, we don't have any Y-haplogroup informantion yet. I don't think it is likely that Fuegians had majority haplogroup Q1a* (or any at all).But then again that's my theory. So what's your take on this?

bicicleur
19-09-14, 18:20
the problem is, America was not accesable during the ice age, because of the Laurentide and Cordillera ice sheets which blocked the entrance from Alaska
so between somewhere between 25 and 30.000 years ago till 16.000 years ago nobody could enter America unless from overseas which I doubt
and there is no solid evidence of human ocupation in America before the ice age, though there are a few hints and lots of discussions about this

personally i don't think there was anybody before Q1a-M3

but if you're looking for a candidate, you might not only look at haplo D but also haplo C1a or C1a1 :
C1a1-M8 is found in Japan only, while C1a2-V20 is found in Europe only, which suggests C1a1 reached Japan through Siberia

C1a1 was probably in Siberia before P, who gave birth to Q and R in Siberia
P probably entered Siberia via the Tashkent area, where Aurignacian-like tools appeared some 45000 years ago
P ousted C1a1 out of Siberia,
and the first modern humans with some more primitive tools arrived in Japan and the Bejing area some 40000 years ago,
I suspect that was C1a1

Power77
19-09-14, 21:01
@bicicleur I like your hypothesis on C1a1*(an haplogroup as coherent with Australoid-like morphology and mtDNA M as D*) but I disagree with your statement saying that people couldn't have reache the Americas 20 000 years ago. I recall that finds in Chile and South America have disproved it.

Aberdeen
20-09-14, 01:31
I've always found the idea people travelling along the coast, possibly even during the last glacial maximum, more credible than the idea of an imaginary ice free corridor. The evidence of that would now be under the sea. As for who actually did travel to the Americas and when, I'd prefer to let the evidence speak for itself once we have a lot more data. But the results of voluntary testing won't give us data about the groups that we need to take a close look at, IMO.

bicicleur
20-09-14, 10:17
I've always found the idea people travelling along the coast, possibly even during the last glacial maximum, more credible than the idea of an imaginary ice free corridor. The evidence of that would now be under the sea. As for who actually did travel to the Americas and when, I'd prefer to let the evidence speak for itself once we have a lot more data. But the results of voluntary testing won't give us data about the groups that we need to take a close look at, IMO.

Mainstream theory now accepts 2 immigration waves : Clovis and pré-Clovis
Pré-Clovis would be the people traveling along the coast, some 16000 years ago, which would explain Mesa Verde, Chile
they don't think it could be earlier, as there were a lot of glaciers running into the sea, whad had to be circumvented
Clovis would be the ice free corridor, 13000 years ago

MOESAN
07-03-15, 23:14
curiously this thread concerning look doesn't speak of look - here I shall speak of look without showing nor describing look: life is full of humor sometimes!

about a abstract given by DIENEKES (Good bless him!)

March06, 2015Craniofacialplasticity in ancient Peru (http://dienekes.blogspot.fr/2015/03/craniofacial-plasticity-in-ancient-peru.html) Anthropologischer Anzeiger doi:10.1127/anthranz/2015/0458

Craniofacial plasticity in ancient Peru

Jessica H. Stone; Kristen Chew; Ann H. Ross; John W. Verano

Numerous studies have utilized craniometric data to explore the roles of genetic diversity and environment in human cranial shape variation. Peru is a particularly interesting region to examine cranial variation due to the wide variety of high and low altitude ecological zones, which in combination with rugged terrain have created isolated populations with vastly different physiological adaptations. This study examines seven samples from throughout Peru in an effort to understand the contributions of environmental adaptation and genetic relatedness to craniofacial variation at a regional scale. Morphological variation was investigated using a canonical discriminant analysis and Mahalanobis D2 analysis. Results indicate that all groups are significantly different from one another with the closest relationship between Yauyos and Jahuay, two sites that are located geographically close in central Peru but in very different ecozones. The relationship between latitude/longitude and face shape was also examined with a spatial autocorrelation analysis (Moran’s I) using ArcMap and show that there is significant spatial patterning for facial measures and geographic location suggesting that there is an association between biological variation and geographic location.




my point:
Always the same type of studies witha predefined goal, here linking mesological adaptation and bonesshape -
the problem is how can we linkdifferences of shapes and dimensions to differences of geographicenvironment – some pre-existing facts can very easily make thingsmore confusing : differences of lignages and attached shapesbefore colonizing the subregion – some later occurrences also, ashazard selected small groups (even if of the same primary mixing :first sort of drift) colonizing different subregions plus subsequentdrift linked to too small numbers : short endogamy...this kindof events, favored by patchworks geography, can produce, even among afirstable level mixture, differences far more striking in metricsmeans than long time and environment evolution when the initialmixture was already composed by neatly distinct elements -
geographic environment and way oflife have evidently impact upon metrics, through selection of genesand lifetime adaptation (the physical activity, oxygenation and bonescontraints has effects during the life, the most from birth untilpuberty), the problem remains quantifying the part of mesologicactions and the one of independant facts inherited from past, remoteor recent -
very often the person making thiskind of study has at some level an agenda and tries, inconscientlysometimes, to prove his prejudice in any possible way -
I would be pleased to have thedetailed conclusions of this study which surely has some good cluesto provide but the difficulty to hop to too hasty conclusions isshown by the morphological proximity of these 2 human groupsgeographically close but in different ecozones as says the abstract(here we need a datation of separation of groups)