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berun
23-05-17, 20:15
From the paper (https://bmcevolbiol.biomedcentral.com/articles/10.1186/s12862-017-0936-9)"A genetic chronology for the Indian Subcontinent points to heavily sex-biased dispersals":


In the last 4 ka, most genetic influx on the maternal line
was restricted to Pakistan and traces mostly to Iran (H29 + 9156 + 4689, R2a + 7142 and U1a1a2a) (2.4% in
South Asia, reaching 5.4% in the western populations).
Gene flow at this time was clearly bi-directional, as seen
in the expansion west of lineages M5a2a4, U2c1b + 146
and M3a1b + 13105). This is reflected in the genomewide
ADMIXTURE analysis (below), where the autochthonous
South Asian component (green in Fig. 2a) appears
at low levels in Iran.


The Yamnaya aDNA samples are scattered around the
Central Asian and Pakistani groups (Additional file 1:
Figure S8), confirming the ADMIXTURE results
(Additional file 1: Figure S6), and suggesting links
between the Bronze Age Steppe and today’s Central Asia
and Indian Subcontinent.

yet Yamnaya, no matter if that was a Copper Age culture.


A markedly higher proportion of male lineages of
likely West Eurasian origin, of ~50–90%, is evident
across the Subcontinent (Fig. 3c), in comparison with
both the maternal line (Fig. 3b) and the GW pattern
(Fig. 3d). A sex-biased pattern is also seen in the East
Asian fraction, but is much less marked, with a much
lower contribution overall and mainly focused on
speakers of Tibeto-Burman and Austroasiatic language
families [22].


Given the difficulties with deriving the
European Corded Ware directly from the Yamnaya [96], a
plausible alternative (yet to be directly tested with genetic
evidence) is an earlier Steppe origin amongst Copper Age
Khavlyn, Srednij Stog and Skelya pastoralists, ~7-5.5 ka,
with an infiltration of southeast European Chalcolithic
Tripolye communities ~6.4 ka, giving rise to both the
Corded Ware and Yamnaya when it broke up ~5.4 ka [12].


There are now sufficient high-quality Y-chromosome
data available (especially Poznik et al. [58]) to be able to
draw clear conclusions about the timing and direction of
dispersal of R1a (Fig. 5). The indigenous South Asian
subclades are too young to signal Early Neolithic
dispersals from Iran, and strongly support Bronze Age
incursions from Central Asia. The derived R1a-Z93 and
the further derived R1a-Z94 subclades harbour the bulk
of Central and South Asian R1a lineages [55, 58], as well
as including some Russian and European lineages, and
have been variously dated to 5.6 [4.0;7.3] ka [55], 4.5–
5.3 ka with expansions ~4.0–4.5 ka [58], or 4.7 [4.0;5.5] ka
(Yfull tree v4.10 [54]). The South Asian R1a-L657, dated
to ~4.2 ka [3.3;5.1] (Yfull tree v4.10 [54]]), is the largest (in
the 1KG dataset) of several closely related subclades
within R1a-Z94 of very similar time depth. Moreover, not
only has R1a been found in all Sintashta and Sintashtaderived
Andronovo and Srubnaya remains analysed to
date at the genome-wide level (nine in total) [76, 77], and
been previously identified in a majority of Andronovo
(2/3) and post-Andronovo Iron Age (Tagar and Tachtyk:
6/6) male samples from southern central Siberia tested
using microsatellite analysis [101], it has also been identified
in other remains across Europe and Central Asia ranging
from the Mesolithic up until the Iron Age (Fig. 5).


Although they are closely related, suggesting they likely
spread from a single Central Asian source pool, there
do seem to be at least three and probably more R1a
founder clades within the Subcontinent [58], consistent
with multiple waves of arrival.


For example, haplogroup H2b (dating to
6.2 ka [3.8–8.7] ka; Fig. 6) is a starlike subclade with a
probable ultimate ancestry in Eastern Europe, but includes
several South Asian lineages (from Pakistan, India and Sri
Lanka) that probably arrived more recently from Central
Asia. Tellingly, H2b also includes two aDNA samples
(Fig. 6): one individual from the small number of Yamnaya
sampled to date [53, 76] and another from the Late
Bronze Age Srubnaya culture [77].


indeed, a
sizeable fraction of the non-R1a West Eurasian Ychromosome
lineages (e.g. R2a-M124, J2-M241, L1a-M27,
L1c-M357) were most likely associated with the spread of
agriculture or even earlier expansions from Southwest
Asia, as with the mtDNA lineages [55, 59]. The

berun
23-05-17, 20:29
Again the info is providing a good track about IE origin: no Yamnaya of course (it was R1b-Z2015), but a R1a population from the steppes related to the CW in the Y-DNA and autosomal admixtures (Andronovo, Sintashta). The ultimate Urheimat only can be found in Kievan Russia.

https://upload.wikimedia.org/wikipedia/commons/f/fb/Kievan_Rus_en.jpg

MarkoZ
24-05-17, 16:36
Again the info is providing a good track about IE origin: no Yamnaya of course (it was R1b-Z2015), but a R1a population from the steppes related to the CW in the Y-DNA and autosomal admixtures (Andronovo, Sintashta). The ultimate Urheimat only can be found in Kievan Russia.

https://upload.wikimedia.org/wikipedia/commons/f/fb/Kievan_Rus_en.jpg

I think Lazaridis mentioned that models involving populations with EEF admixture are rejected for India. This would mean Europe is out of the picture.

Tomenable
24-05-17, 16:41
I think Lazaridis mentioned that models involving populations with EEF admixture are rejected for India. This would mean Europe is out of the picture.

Early East Baltic Corded Ware had no EEF admixture.

Much of Eastern Europe had little to no EEF influence.

MarkoZ
24-05-17, 16:52
Early East Baltic Corded Ware had no EEF admixture.

Much of Eastern Europe had little to no EEF influence.

Right, but a migration from Latvia into India without intermediate cultures would be quite difficult to conceive of. Lazaridis thinks Sintashta-Petrovka as a source is falsified.

berun
24-05-17, 19:36
I have had the same thinking as Tomenable, but even in the paper they find EEF-like component in Punjabis, Makrits and Brahui (or Baluchi), this region would be the first to be settled coming from the Asian steppes, if the invasion was slow their original admixture of the steppe IE could be diluted enough as to leave thin tracks of it in secondary expansions. Otherwise I'm not much confident about admixture models as the data provided is allways partial.

holderlin
24-05-17, 21:44
PIE is looking more and more like the Steppe-Balkan interface rather than the steppe itself.

holderlin
24-05-17, 21:47
Early East Baltic Corded Ware had no EEF admixture.

Much of Eastern Europe had little to no EEF influence.

I would consider that early CWC culture sample to be an exception. Very soon after all of CWC has EEF as does the entire steppe by the middle bronze age.

halfalp
25-05-17, 14:11
PIE is looking more and more like the Steppe-Balkan interface rather than the steppe itself.

Well if you think that because of the recent R1b found in the Iron Gates, Iron Gates is in the frontier with the Wallachian Plain, wich is a continuity of the Pontic Steppe, wich is a part of the Eurasian Steppe. R1b definitely sound steppique, technically, all peripheric territories of eurasian steppe, at least up to central asia, can be linked with R1b ( Italie by pontic steppe, wallachian plain, iron gates, pannonian plain, padan plain..., Balkans, Baltic, Caucasus, even Iran ) one way or another.

berun
25-05-17, 17:27
you forgot the Baltic and German R1b HG, but well, being a case of steppitis it's all right.

halfalp
25-05-17, 18:53
you forgot the Baltic and German R1b HG, but well, being a case of steppitis it's all right.

Both Germany and Balt states are peripheric of plain area, southern bug and northern bug, with vistule makes you go on the baltic, and by following the danube you going in germany. Also both are in the great european plain, there is no natural frontier, like mountains, and this rules is more prevalent in last glacial period were mountains were litteraly impassable. So plains and rivers must have been the natural roads for all population want to go in europe, apart of an southern coastal mediterranean road.

berun
25-05-17, 19:28
Ok, if you don't like to take Ibuprofen you might check that German and Latvian Mesolithic HG had an origin in the Magdalenian, far away from the steppes. By the way the plains have not phisical frontiers, but human bands are prone to set invisible frontiers quickly.

MarkoZ
25-05-17, 20:19
you forgot the Baltic and German R1b HG, but well, being a case of steppitis it's all right.

Not to mention that Yamnaya R1b-Z2103 seems to have higher basal diversity in the southern Caucasus.

Imho that would make an origin in the Balkans unlikely.

Apsurdistan
25-05-17, 20:24
Nobody seems to mention the woods and forests. I can't imagine they were easy to pass through and live in for the farmers and pastoralists. And they were even more dense and widespread in the past than they are now. Must have been much harder to pass through those than it is n modern times specially for large scale migrations.

halfalp
25-05-17, 21:22
Both Germany and Balt states are peripheric of plain area, southern bug and northern bug, with vistule makes you go on the baltic, and by following the danube you going in germany. Also both are in the great european plain, there is no natural frontier, like mountains, and this rules is more prevalent in last glacial period were mountains were litteraly impassable. So plains and rivers must have been the natural roads for all population want to go in europe, apart of an southern coastal mediterranean road.

Magdalenian is totally linked with mt haplogroup U5b and not with R1b.

halfalp
25-05-17, 21:31
Not to mention that Yamnaya R1b-Z2103 seems to have higher basal diversity in the southern Caucasus.

Imho that would make an origin in the Balkans unlikely.

There is no origin of an haplogroup, but association with an archeologic culture, say haplogroup I originate in europe, or R1b in the steppe or armenian highlands, doesn't mean anything. The point is, R1b is a major haplogroups of the european Epigravettian, thats gonna be shows more and more in the future, plus, cultures are never static and demographic even less. One point about transcaucasus, that people not think about it, its that after LGM north and south could have meet together, following the valleys previously impenetrable. So R1b is definitly of the steppe, the point is, that pontic steppe is huge, and R1b people from volga, and hypothetic R1b from south steppe caucasus range or caspian, could have been slightly differents, mixing with transcaucasus people, and have a new genetic flow, lead by women-like input.

MarkoZ
25-05-17, 22:43
There is no origin of an haplogroup, but association with an archeologic culture, say haplogroup I originate in europe, or R1b in the steppe or armenian highlands, doesn't mean anything. The point is, R1b is a major haplogroups of the european Epigravettian, thats gonna be shows more and more in the future, plus, cultures are never static and demographic even less. One point about transcaucasus, that people not think about it, its that after LGM north and south could have meet together, following the valleys previously impenetrable. So R1b is definitly of the steppe, the point is, that pontic steppe is huge, and R1b people from volga, and hypothetic R1b from south steppe caucasus range or caspian, could have been slightly differents, mixing with transcaucasus people, and have a new genetic flow, lead by women-like input.

I guess what people are interested in are the star-like expansions of L51 and Z2013 respectively. IMHO, both should predate Yamnaya expansion, though it may be too early to tell for sure.

The origin of L23 at which they separated is even less clear. I think R1b-L23 has a lot of diversity in the region streching from Iraq to Albania so maybe somewhere inbetween?

bicicleur
26-05-17, 07:47
IMO the bulck of CHG in India got there by R2 and J2 herders from the Zagros mountains in the early neolithic, 9 ka
this CHG component was the first to get there after the native component, which was there allready before LGM
in spite of what the study claims, I think India was pretty isolated during LGM and even later, till 9 ka