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MOESAN
31-10-11, 16:08
hello

sorry for my curious english

here some thinkings about the matter:

1st post to Eupedia


The problem of number and density in the ancient populations : it should have some impact on the interpretations we can do about the possible bottlenecks and founder effects, and also on the mobility of these populations and the impact of genetic admixtures. What I believe is that the more the period is close to our time the more the Europe people was numerous and the minder all these accidental phenomenons are likely to have taken place. What should be very interesting should to have good datas about the Europe population through the ages. Archeolology is of great worth in helping to measure the density of human populations even if the different quality of soils and reliefs can be obstacles to the understanding of reality. When a read very often there was nobody out of the southern refuges I the Last Glacial Maximum I am not so convinced. Archeology shows that there was some people in the northern central Europe in the middle of these ages even if the density was inferior to the one of the refuge regions. When I think to the very different phenotypes (metrical and others) found in Europe I can not imagine they could be caused by big repopulating movements. I am aware of the contempt about traditional physical anthropology. By the way phenotypes are caused by genotypes (with some distortions) and the human beings was fewer and fewer under natural selection. The external phenotypes are maybe fewer under selection than other autosomals like those of the blood. I am obliged to imagine several little zones inhabited by a few peoples and isolated each from the other. It is not only a matter of time for selecting genes but above all a matter of needed isolation for the process of selection on a necessary little enough number of men: phenotypes can not be so new in despite of some claims, I believe. Consequence: it is very possible that some of the core of present days numerous enough marginal populations was at the beginning small populations whose demography knew a big boom: not at one time only but at several periods, not the same for all peoples. A metric type (based on serious studies and a lot of scientific considerations) can not find place without these conditions. There is no need to say that after these periods of isolating these populations were less or more submitted to crossings, light or heavy according to every history. The problem stays there: isolating and growing up, but where and when?
All these aspects have their weight because a maintained small level of population can lead to two contrary results (“law of the small numbers”?): a old SNP based HG without new branches even if far from its origin place OR a new HG staying yet in “native” place its anceytors. It does not happen every time but it can occur sometimes. The STRs are of no use in the case of very different HGs based on SNPs. They just can tell us something on age when they are diverse AND star like, knowingthat some back migrations can send back other STRs. The Caucasus shows very near (geographically & in regard of autosomals) populations, isolated by relief even more than by culture, and with very different, often opposite in distributions of HG-Y (almost not coding), even when sharing the same culture! So isolation (passed and present) by relief or distance can bias the timing of the story and the scenario and it is very important to do with other ways of approach like binary alleles, metrics and non metric physical studies (reflecting incompletely work of binary alleles) and demographic studies when possible. It is sure the weight of isolation and deriving became lighter and lighter as time passed.

MOESAN
17-11-11, 22:30
[QUOTE=MOESAN;385312]hello

sorry for my curious english

here some thinkings about the matter:

1st post to Eupedia


The problem of number and density in the ancient populations : it should have some impact on the interpretations we can do about the possible bottlenecks and founder effects, and also on the mobility of these populations and the impact of genetic admixtures. What I believe is that the more the period is close to our time the more the Europe people was numerous and the minder all these accidental phenomenons are likely to have taken place. What should be very interesting should to have good datas about the Europe population through the ages. Archeolology is of great worth in helping to measure the density of human populations even if the different quality of soils and reliefs can be obstacles to the understanding of reality. When a read very often there was nobody out of the southern refuges I the Last Glacial Maximum I am not so convinced. Archeology shows that there was some people in the northern central Europe in the middle of these ages even if the density was inferior to the one of the refuge regions. When I think to the very different phenotypes (metrical and others) found in Europe I can not imagine they could be caused by big repopulating movements. I am aware of the contempt about traditional physical anthropology. By the way phenotypes are caused by genotypes (with some distortions) and the human beings was fewer and fewer under natural selection. The external phenotypes are maybe fewer under selection than other autosomals like those of the blood. I am obliged to imagine several little zones inhabited by a few peoples and isolated each from the other. It is not only a matter of time for selecting genes but above all a matter of needed isolation for the process of selection on a necessary little enough number of men: phenotypes can not be so new in despite of some claims, I believe. Consequence: it is very possible that some of the core of present days numerous enough marginal populations was at the beginning small populations whose demography knew a big boom: not at one time only but at several periods, not the same for all peoples. A metric type (based on serious studies and a lot of scientific considerations) can not find place without these conditions. There is no need to say that after these periods of isolating these populations were less or more submitted to crossings, light or heavy according to every history. The problem stays there: isolating and growing up, but where and when?


I answer to ma own question !
not, just to open some path
My aim was discuss the dating of Y-R1b in Western Europe (and others) and the maybe too high comfidence given to the STR 's time évaluations - I'm sure of nothing here and I know that R1 or any kind of R are absent of the ancient Y DNA testings in old old Europe - but what Mesolithic or Paleolithic remnants have been tested for Y DNA for now? Tank you for your answer.

sparkey
17-11-11, 22:56
I answer to ma own question !
not, just to open some path
My aim was discuss the dating of Y-R1b in Western Europe (and others) and the maybe too high comfidence given to the STR 's time évaluations - I'm sure of nothing here and I know that R1 or any kind of R are absent of the ancient Y DNA testings in old old Europe - but what Mesolithic or Paleolithic remnants have been tested for Y DNA for now? Tank you for your answer.

I agree that Y-STR dating has low confidence, although it's nonetheless still very helpful for tracing migrations.

So far no European Y-DNA from the Mesolithic or Paleolithic have been tested. A few Neolithic samples have been tested, turning up mostly G2a, along with others like I2a1a (Treilles, in France), E1b-V13 (Epicardial, in Iberia), and F* (LBK, in Germany; Maciamo thinks that this is a false F* and is more likely actually J1). We also have Corded Ware confirmed as R1a.

Jean Manco has a good summary here (http://www.buildinghistory.org/distantpast/ancientdna.shtml).

MOESAN
17-11-11, 23:18
I agree that Y-STR dating has low confidence, although it's nonetheless still very helpful for tracing migrations.

So far no European Y-DNA from the Mesolithic or Paleolithic have been tested. A few Neolithic samples have been tested, turning up mostly G2a, along with others like I2a1a (Treilles, in France), E1b-V13 (Epicardial, in Iberia), and F* (LBK, in Germany; Maciamo thinks that this is a false F* and is more likely actually J1). We also have Corded Ware confirmed as R1a.

Jean Manco has a good summary here (http://www.buildinghistory.org/distantpast/ancientdna.shtml).

thank you for kind answer - I've heard for some of the Neolithic sites but as you, sure, I keep thursty about Mesolithic Y and mt DNA!

MOESAN
19-12-11, 21:06
I agree that Y-STR dating has low confidence, although it's nonetheless still very helpful for tracing migrations.

So far no European Y-DNA from the Mesolithic or Paleolithic have been tested. A few Neolithic samples have been tested, turning up mostly G2a, along with others like I2a1a (Treilles, in France), E1b-V13 (Epicardial, in Iberia), and F* (LBK, in Germany; Maciamo thinks that this is a false F* and is more likely actually J1). We also have Corded Ware confirmed as R1a.

Jean Manco has a good summary here (http://www.buildinghistory.org/distantpast/ancientdna.shtml).

I add: there are a lot of discussions about the absence of Y-R1b in Western Europe during the Paleolithic and the Mesolithic periods: on what are they based? we have NO Y-DNA studied today... and for the Neolithic, the settlements studied are from regions of known neolithic big density (S-E Spain, & S- France cardial, german LBK - I should be glad to read about other types of settlements in remote regions

sparkey
19-12-11, 21:33
I add: there are a lot of discussions about the absence of Y-R1b in Western Europe during the Paleolithic and the Mesolithic periods: on what are they based? we have NO Y-DNA studied today...

This is based mainly on STR dating and SNP geographic diversity analysis. They inform us that R1b is relatively young, especially L11 subclades (http://www.eupedia.com/forum/showthread.php?27049-More-precise-R1b-subclade-estimates-using-Nordtvedt-s-methodology), by far the most common in Western and Central Europe. R1b is very Asian as a whole; only a couple of relatively young subclades (L11 and ht35) are notably common in Europe, along with some rare L11- L51+ "proto-L11"-type subclades. This suggests that modern R1b-L11 is a rapid expansion upon Western and Central Europe, quite possibly dating to the Bronze Age.

That analysis basically rules out a Paleolithic or Mesolithic origin for R1b-L11. I don't know as much about R1b ht35, though, and I suppose it's not impossible that an extinct branch of R1b could have been in Europe a long time before either of those two. But there's no evidence that there was.


and for the Neolithic, the settlements studied are from regions of known neolithic big density (S-E Spain, & S- France cardial, german LBK - I should be glad to read about other types of settlements in remote regions

I agree that these are geographically biased, and that's one reason why we've seen nonstop G2a... these have been the places that G2a dominated at that time. I suspect that more remote areas along the Atlantic Fringe and the Upper Rhine would find more Haplogroup I, and more Eastern samples will find a greater variety of Neolithic introductions, maybe even some R1b (but probably L11-).

MOESAN
20-12-11, 00:35
This is based mainly on STR dating and SNP geographic diversity analysis. They inform us that R1b is relatively young, especially L11 subclades (http://www.eupedia.com/forum/showthread.php?27049-More-precise-R1b-subclade-estimates-using-Nordtvedt-s-methodology), by far the most common in Western and Central Europe. R1b is very Asian as a whole; only a couple of relatively young subclades (L11 and ht35) are notably common in Europe, along with some rare L11- L51+ "proto-L11"-type subclades. This suggests that modern R1b-L11 is a rapid expansion upon Western and Central Europe, quite possibly dating to the Bronze Age.

That analysis basically rules out a Paleolithic or Mesolithic origin for R1b-L11. I don't know as much about R1b ht35, though, and I suppose it's not impossible that an extinct branch of R1b could have been in Europe a long time before either of those two. But there's no evidence that there was.



I agree that these are geographically biased, and that's one reason why we've seen nonstop G2a... these have been the places that G2a dominated at that time. I suspect that more remote areas along the Atlantic Fringe and the Upper Rhine would find more Haplogroup I, and more Eastern samples will find a greater variety of Neolithic introductions, maybe even some R1b (but probably L11-).


L11: yes (I don't forget that R-L11 is born on R-L51) - but how to date it? the variety of a SNP is depending on time but also on number... a bottleneck can be old enough before reexpanding of the human group of bearers - I know I 've no good answer to this problem of variance -
hypothesis:
1- a scarce population L11 in central Europe at the Bronze Age: after crossing Europe from East to West they should have been mixed with others numerous HGs and how to explain that only R1b could have prospered and the others been almost dropped out? -
1bis - a few people too but without mixture: how to explain they should have dispatched thin families on every direction of Europe upon a big territory to produce the present day pattern of R1b - I think this hypothesis of a small number could only apply to a precedent period -
2- a big population yet in central Europe? how to explain they could have separated so clearly their different dowstream lineages living side by side to produce the present day pattern (and yet, after modern Histroy came upon with its mixing events) - and how to explain the paucity of L11 then (if they was numerous enough at this time) -an upstream HG can disappear (almost) after a very long time and after giving a lot of branches: here it seams we have only P310 ?

I agree you have good arguments on your side, but I have some good questions: sure we lack some elements - for U106 I believe it could have gone apart somewhere more in the North (a distinct branch of P310 >> S.Baltic???) - two ways for R1b westward: Baltic and Danube? the lack of P310 in N-E Europe could be caused by the very low percentages of R1b there?

all the way I confess I have more questions than answers and I'm not 100% opposed to your point of vew - I hesitate.