As we move onto the new year we look back at the past decade which saw significant progress within the field of population genomics.
At the beginning of the decade the field was practically non existent. Stuck in the mire of old Palaeolithic continuity nonsense espoused by the likes of Stephen Oppenheimer and his colleague Brian Sykes. Similar sentiments existed in the archaeological community, and had done since WWII.
Without any ancient samples as a point of reference, these ‘experts’ based their theories near exclusively on uniparental markers, claiming that haplogroup R1b the dominant lineage of Western Europe was an old Palaeolithic lineage that spread in post-LGM migrations from the Franco Cantabrian refuge, due to it being most prevalent there, so it must’ve come from there.
Right?
Wrong. As it turns out basing one’s finding on just FOUR short tandem repeat Y-chromosomal markers doesn’t really tell you all that much about one’s own genome. Actually looking at the genome tells us more about the genome. There were plenty of burials to plunder for samples. There was just one problem.
The cost. To sequence a single sample would cost tens of thousands of dollars and the finished product was always vulnerable to contamination, ala Mr.David Reich (pbuh) of Harvard university steps in and completely changes everything with his groundbreaking work. The revolutionary NGS (Next Gen Sequencing) illumina SNP array utilised in UDG (Uracil DNA Glycosylase) treated labs were able to sequence these ancient samples at relatively low cost (under $200 same price for most consumer kits) and to relatively high coverage depending on the quality. By 2013 the genomic revolution had already gone well underway, and it was discovered that Europeans form a genetic cline between three modal “ghost” populations. Geneticists were perplexed by this.
The only thing to do was dig up more samples from various sites across the continent. Since 2013 up until now close to two thousand samples have been sequenced with many more well on the way.
Eventually that year a team of archaeologists dug up the remains of a four year old child buried in the permafrost in a site located in central Siberia associated with the Mal’ta Buret culture. The child had been frozen for close to twenty four thousand years. Reich’s team managed to get their hands on a sample from the petrous bone where the DNA is best preserved and it was revealed this child belonged to a population (dubbed Ancient North Eurasians) that made up one of the particular “ghost” populations ancestral to modern Europeans, as well as to middle easterners and even more so in Native American populations. The boy’s paternal haplogroup was found out to be R* basal to the vast majority of paternal lineages found in European men today (R1a and R1b).
With regards to the autosomes, his DNA was found to be higher in present day Northern and Eastern Europeans (15-25%) and Southern Europeans (5-15%) to a lesser degree, and in Sardinians almost totally absent.
Why was this? Surely these Siberian ice age mammoth hunters had nothing to do with us? How did their DNA get all the way over here in Ireland, and for that matter why are nearly all Irishmen directly descended from them? This is when population genetics really starts to get intriguing. And somewhat also confusing.
Obviously these ANE foragers had no presence in our part of Eurasia, so as always there had to have been a middle man which brought this type of ancestry to Europe. In 2015 a study headed by a team of Irish geneticists at trinity college sequenced four samples from the Neolithic and later Bronze Age. The neolithic woman from Ballynahatty was found to totally lack this ANE component and thus resembled present day Sardinians, whilst the three Bronze Age men that replaced her population scored a significant amount. Even more than modern Irish people as a matter of fact.
Where did these Bronze Age Irish inherit this from you ask? In steppes the Yamnaya culture. (See what I did there?)
Almost no continuity with neolithic Irish. |
Strong continuity with Bronze Age Irish. |
Amongst the vast majority of archeologists and geneticists. The Yamnaya (Pit-Grave in Russian) herders of southern Russia are the best candidate for spreading Proto-Indo-European dialects into Europe and subsequently after mixing with local farmer populations, bringing proto-Indo-Aryan dialects to central and Southern Asia too, along with their genes. They lived in a predominantly pastoral economy though they occasionally cultivated grains to bolster their food supply. They were a brutal and aggressive people whom championed violence above all things as evidenced by their remains frequently showing signs of blunt force trauma from cudgel like weapons. They buried their dead individually in burial mounds known as “kurgans” and judging from the lack of females found they were likely a patriarchal society, as all subsequent Indo-European cultures were. This is also further evidenced in phylogenetic findings showing these men to belong to the same terminal Y-SNP, implying patrilineality similar to the clan systems of Gaelic Ireland which placed a strong emphasis on a common male ancestor. As it turns out 84% Irishmen also share a common male ancestor with the yamnaya men going back some six millennia ago to somewhere in the pontic steppe region.
These late PIE populations were themselves roughly 40-50% ANE, and formed a cline between Eastern European hunter gatherers (70% ANE+ 25% WHG+ 5% CHG) and Caucasus hunter gatherers (50% ANE + 50% Dzuaduana like population). Predominantly made up of the former rather than the latter. Men from EHG tribes interbred with women from CHG tribes and resulting meta population expanded into the Don-Kuban region assimilating the EHG rich forager groups there. The ethnogenesis of yamnaya related populations likely occurred like this.
I, for one, welcome our new steppe overlords. |
The first academic to hypothesise these people for being responsible for spreading Indo-European language was ironically feminist Lithuanian scholar Marija Gimbutas, who contrasted them with the opposing “old European” populations of neolithic Europe whom lived in sedentary and agricultural societies counter to the more on the go Yamnaya.
She saw the neolithic farming populations as pacifistic, gynocentric and egalitarian, more sophisticated than the vicious steppe warlords to the east. Despite some evidence to the contrary.
Even more ironic being that Lithuanians like her are one of the closest modern populations to the yamnayans. Perhaps explaining why they speak one of the most archaic Indo-European languages?
No wonder Khabib defeated McGregor! |
In a massive multidisciplinary study headed by lead geneticist Wolfgang Haak in 2015 entitled “Massive migration from the steppe was a source for Indo-European languages in Europe” (you can read it here) the authors concluded that a majority of Northern/Eastern European DNA derived from these herders, along with Indo-European speech as evidenced by the presence of farmer enriched steppe admixture in Indo-Aryan speakers. The kurgan model of Gimbutas had been vindicated.
In 2018 a study headed by Iñigo Olalde discovered the middle man for this steppe ancestry found in present day northwest Europeans were bell beaker cultures of Central Europe.
By 2400BC there was at least 90% turnover from local megalithic builders who left little to no introgression into the modern Irish genome.
My models more or less falling in line with señor Olade’s findings. |
We have learned a lot in the previous decade of population genomics research and we hope to discover even more about ourselves in this one.
With the thesis of Lara Cassidy’s “A Genomic Compendium of an Island:Documenting continuity and change across Irish human prehistory” under embargo until May of this year, we will not have to wait long until we get our filthy hands on close to one HUNDRED samples from the mesolithic right up into the medieval period.
With this publication of so many samples my work on Ireland’s various genomic transitions will be more or less complete.
Previously Irish scholars maintained that we are Atlantean, when in reality we are Hyperborean. And always have been, whether or not we remain so remains to be seen.
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