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rms2
07-06-2018, 12:59 PM
Here's a new paper that should be coming out in the next year or so. There will be a presentation on it at the SMBE (Society for Molecular Biology and Evolution) Conference in Yokohama, Japan, on July 11 (the conference is being held from July 8-12).




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The Genomics of Megaliths: An Irish case study into the reconstruction of prehistoric societal landscapes through ancient DNA analysis

Lara M Cassidy 1

1 Trinity College Dublin (Ireland)

The Irish Neolithic (circa 3,800-2,500) marks the emergence of complex civilization on the island, alongside the establishment of continued contacts with other Atlantic regions, which intensify in the succeeding Copper and Bronze Ages. In addition to these cultural upheavals, the Neolithic period has been demonstrated to both begin and end with mass migration into the island, potentially from multiple external sources. However, the variable interplay between geography and culture in the catalyzation of these population movements has remained an open question. Indeed, the archaeological record would suggest regional heterogeneity in the uptake of British and continental traditions at both transition points.

Here, the potential social and cultural implications of such events are explored through the prism of ancient genomics. Imputed diploid genotypes for over 50 individuals sampled from the Mesolithic to Bronze Age periods, encompassing a diversity of megalithic structures, are presented and dissected through the use of haplotypic-sharing methods, as well as estimations of kinship and inbreeding. Combined with Y chromosome analysis these provide the first evidence of genetic structure on the island during specific prehistoric time intervals, which can be interpreted along both geographical and cultural lines. Furthermore, candidate refugiums that may recurrently act as reservoirs for older traditions and genetic ancestries are identified, as well as hub regions, which appear more susceptible to demographic disturbances on the continent, highlighting the immovable constraints of geography on both cultural and genomic evolution.


Notice the part I put in bold red above. Pretty obviously they mean the mass arrival of Neolithic farmers at the start of the Neolithic and of Kurgan Bell Beaker people at the end of it. I am really interested in how that played out genomically and how much population replacement occurred, especially with the arrival of the Kurgan Bell Beaker people.

Lara Cassidy was the lead author of the Cassidy et al paper on the Rathlin Island men. This should also be a great paper.

caithne
07-06-2018, 08:18 PM
Leabhar Gabhála Éireann investigated with ancient dna analysis! Is trom an t-ualach an t-aineolas.

rms2
07-07-2018, 01:37 PM
Leabhar Gabhála Éireann investigated with ancient dna analysis! Is trom an t-ualach an t-aineolas.

I don't speak Gaelic, but I used Google Translate on that. It came up with



The burden of ignorance is heavy.


Perhaps you'd care to explain what you meant (in English, please).

etrusco
07-07-2018, 01:59 PM
Here's a new paper that should be coming out in the next year or so. There will be a presentation on it at the SMBE (Society for Molecular Biology and Evolution) Conference in Yokohama, Japan, on July 11 (the conference is being held from July 8-12).




Notice the part I put in bold red above. Pretty obviously they mean the mass arrival of Neolithic farmers at the start of the Neolithic and of Kurgan Bell Beaker people at the end of it. I am really interested in how that played out genomically and how much population replacement occurred, especially with the arrival of the Kurgan Bell Beaker people.

Lara Cassidy was the lead author of the Cassidy et al paper on the Rathlin Island men. This should also be a great paper.


These analyses, taken with the PCA and ADMIXTURE results, indicate that the Irish Bronze Age is composed of a mixture of European MN and introgressing Steppe ancestry (9, 10). To estimate the proportion of Yamnaya to MN ancestry in each Irish Bronze Age sample, we took three approaches. First, from ADMIXTURE analysis (Fig. 1), we examined the green Caucasus ancestry component. We presume an ultimate source of this as the Yamnaya where it features at a proportion of 40% of their total ancestry. In our three Irish Bronze Age samples, it is present at levels between 6–13%, which, when scaled up to include the remaining 60% of Yamnaya ancestry, imply a total of 14–33% Yamnaya ancestry and therefore 67–86% MN in the Irish Bronze Age. Second, for each Bronze Age Irish individual, we calculated the proportion of MN ancestry by using the ratio f4(Mbuti, Ballynahatty; X, Dai)/f4(Mbuti, Ballynahatty; Gok2, Dai), which gave estimates between 72 ± 4% to 74 ± 5%, implying again a substantial Yamnaya remainder. Third, we followed the methods described in Haak et al. (9), which use a collection of outgroup populations, to estimate the mixture proportions of three different sources, Linearbandkeramik (Early Neolithic; 35 ± 6%), Loschbour (WHG; 26 ± 12%), and Yamnaya (39 ± 8%), in the total Irish Bronze Age group. These three approaches give an overlapping estimate of ∼32% Yamnaya ancestry.

I tought Yamnaya was a good chunck more than 32%.

rms2
07-07-2018, 02:41 PM
. . .

I tought Yamnaya was a good chunck more than 32%.

That earlier paper is somewhat dated now. We have acquired a good many more results since then, and evidently Yamnaya ancestry has been further refined. Recently, Davidski remarked that with what we know now, Bell Beaker could have been as much as 80-90% steppe.

The fact that Yamnaya itself has lately been shown to contain a Globular Amphora-like ENF element will probably change things.

Notice the proximity of Rathlin 1 and 2 to Yamnaya_Kalmykia in the table from Eurogenes below:

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This qpGraph shows British Kurgan Bell Beaker derived from Yamnaya.

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caithne
07-08-2018, 08:29 AM
In the past when the Book of Invasions was taken as a literal history of Ireland it was the first chapter of Irish history text books. Then the narrative changed the ancient writings were mostly myths and a result of the early Irish monks wish to create an Irish identity within the wider early Christian Church. Historians, linguists and archaeologist were aware that we are not an island in isolation from Britain and the rest of Europe there were many migrations of people and culture. I believe that most Irish people accepted that many peoples were part of our ancient past. We now have the opportunity to know through ancient DNA analysis our ancient history. We will have more clarity and our lack of knowledge can no longer be a cause for uncertainty. Our recent past has been a story of lost people and a near total loss of our history, language and culture. I look forward to all the new knowledge we will gain and the new and more complete story we can create.

rms2
07-08-2018, 10:53 AM
This should be the mega-paper of Irish prehistory, that's for sure, with over 50 samples from the Mesolithic to the Early Bronze Age.

It's something to really look forward to. I just hope they publish it pretty soon and we don't have to wait too long.

This summer would be nice, since I'm a teacher and don't work in the summer. That would give me plenty of time to read and digest it.

But do these researchers ever publish a paper in the summertime? Not that I recall. They always seem to put them out when I am really busy with work.

glentane
07-08-2018, 11:27 AM
This should be the mega-paper of Irish prehistory, that's for sure, with over 50 samples from the Mesolithic to the Early Bronze Age.

It's something to really look forward to. I just hope they publish it pretty soon and we don't have to wait too long.

This summer would be nice, since I'm a teacher and don't work in the summer ...
... But do these researchers ever publish a paper in the summertime? Not that I recall. They always seem to put them out when I am really busy with work.

Er, mate, no offense, but that's because all academic types are on their jollies for months in the summer, a bit like you.

rms2
07-08-2018, 11:29 AM
Er, mate, no offense, but that's because all academic types are on their jollies for months in the summer, a bit like you.

True. I did actually think of that.

Soon I will be retired and off for good. Hope my mind holds up so that I can still understand these papers when I can devote more time to them.

glentane
07-08-2018, 11:37 AM
True. I did actually think of that.Archaeologists are the worst offenders.
Out of the office, frequently out of the country, and very often in remote wilderness areas without cellphone cover, electricity, or washing water.
Down a hole. Possibly with an owl.

caithne
07-08-2018, 12:13 PM
Considering the amount of wind and rain in Ireland during the whole year, Summer is probably the best time for archaeologist, except when they're on a picket line striking for better pay. Irish Examiner headline from 4 days ago "Archaeologists working on Macroom bypass strike over pay row."

glentane
07-12-2018, 11:25 PM
Summer is probably the best time for archaeologist, except when they're on a picket line striking for better pay."

Ar. You'm bi wantin' directions then


https://www.youtube.com/watch?v=q_a1wxqloEs

We've all been there. eh?

rozenfeld
07-14-2018, 04:54 AM
Crosspost here, because it seems relevant:

I found this video on Youtube: https://www.youtube.com/watch?v=Lyg7miRrxPA


Dr. Robert Hensey: "Newgrange: A Shared Past, A Shared Future" | Talks at Google

Published on Jul 13, 2018

How could such a stupendous structure as Newgrange have been built so long ago? Where did its builders come from? Dr. Robert Hensey, a research archeologist, who specializes in the Irish Neolithic period and author of the book "First Light: The origins of Newgrange" takes us on a journey into Irelands past.

At 25:55 he very briefly talks about ancient DNA results from Carrowkeel tombs.

rms2
07-30-2018, 09:22 PM
Off topic, but in the video above I noticed the back of this guy's head because the hair growth down the left side of the nape of his neck is the same as mine and that of my sons. I have noticed that in other people, as well, and have wondered if it has any ancestral significance.

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