Razib Khan One-stop-shopping for all of my content

May 10, 2017

The Bronze age demographic transformation of Britiain

Filed under: Bell Beaker,Britain,Evolution,History,Human Genetics,Human Genomics — Razib Khan @ 8:52 am

In Norman Davies’ the excellent The Isles: A History, he mentions offhand that unlike the Irish the British to a great extent have forgotten their own mythology. This is one reason that J. R. R. Tolkien created Middle Earth, they gave the Anglo-Saxons the same sort of mythos that the Irish and Norse had.

But to some extent I think we can update our assessments. Science is bringing myth to life. The legendary “Bell Beaker paper” is now available in preprint form, The Beaker Phenomenon And The Genomic Transformation Of Northwest Europe. The methods are not too abstruse if you have read earlier works on this vein (i.e., no Nick Patterson authored methodological supplement that I saw). And the results are straightforward.

And what are those results?

First, the Bell Beaker phenomenon was both cultural and demographic. Cultural in that it began in the Iberian peninsula, and was transmitted to Central Europe, without much gene flow from what they can see. Demographic in that its push west into what is today the Low Countries and France and the British Isles was accompanied by massive gene flow.

In their British samples they conclude that 90% of the ancestry of early Bronze Age populations derive from migrants from Central Europe with some steppe-like ancestry. In over words, in a few hundred years there was a 90% turnover of ancestry. The preponderance of the male European R1b lineage also dates to this period. It went from ~0% to ~75-90% in Britain over a few hundred years.

If most of the genetic-demographic character of modern Britain was established during the Bronze Age*, then there has been significant selection since the Bronze Age. The figure to the left shows ancient (Neolithic/Bronze age) frequencies of selected SNPs, with modern frequencies in the British in dashed read. The top-left SNP is for HERC2-OCA2, the region related to brown vs. blue eye color, and also associated with some more general depigmentation. The top-right SNP is in SLC45A2, the second largest effect skin color locus in Europeans. The bottom SNP is for a mutation on LCT, which allows for the digestion of milk sugar as adults.

The vast majority of the allele frequency change in Britons for digestion of milk sugar post-dates the demographic turnover. In other words, the modern allele frequency is a function of post-Bronze Age selection. This is not surprising, as it supports the result in Eight thousand years of natural selection.

1000 Genomes derived SLC45A2 SNP frequency

At least as interesting are the pigmentation loci. The fact that the derived frequency in HERC2-OCA2 is lower in both British and Central European Beaker people samples indicates that the lower proportion is not an artifact of sampling. Britons have gotten more blue-eyed over the last 4,000 years. Second, SLC45A2 is at shocking low proportions for modern European populations.

HGDP derived SLC45A2 SNP frequency

In the 1000 Genomes the 4% ancestral allele frequency is almost certainly a function of the Siberian (non-European) ancestry. In modern Iberians the ancestral frequency is 18% (and it is even higher in Sardinians last I checked), but in Tuscans it is ~2%. Though not diagnostic of Europeans in the way the derived SNP at SLC24A2 is, SLC452 derived variants are much more constrained to Europe. Individuals who are homozygote ancestral for SNPs atSLC45A2 rare in modern Northern Europeans (pretty much nonexistent actually). But even as late as the Bronze Age they would have been present at low but appreciable frequencies.

This particular result convinces me that the method in Field et al. which detected lots of recent (last 2,000 years) selection on pigmentation in British populations is not just a statistical artifact. Though these papers are solving much of European prehistory, they are also going to be essential windows into the trajectory of natural selection in human populations over the last 5,000 years.

* In the context of this paper the Anglo-Saxon migrations tackled by the PoBI paper are minor affairs because the two populations were already genetically rather close. Additionally, the PoBI paper found that the German migrations were significant demographic events, but most of the ancestry across Britain does date to the previous period.

February 5, 2011

British, Brown & Diverse but accepting (The story of the Lioness and her Prey inside)

My 18mth old nephew and mother have caught a virus, which means I’m staying in tonight. Luckily (or perhaps not) for Brown Punditry that means I’ll be manning my station, while occasionally checking up on my family (my sister-inlaw has entered her delivery period so Feb is going to be an interesting month isA). I come through as quite gossipy and personal and that’s also a reason why I am never controversial (apart from the occasional flirtation with Pakistaniat but even that’s fairly mild and comical). I’m no good at anonymity (nor is my family come to think of it; to my advantage and detriment I integrate all aspects of my life wherever possible) so like many mystic Shi’ites I have many opinions (several layers of opinions in fact) and ocassionally practise Ta’aqiyah (dissimulation) when it suits. Just because I avoid controversy doesn’t mean I don’t have opinions, its just that they are going to be very subtle and balanced to avoid offending anyone.

Britain and Diversity

Prime Minster Cameron today said that Multi-culturalism has failed in Britain. Britain is an amazing country, extremely humanitarian and very open-minded, but unfortunately society here is dealing with its own issues of assimilation & ghettoisation. The EDL (English Defence League) marched in Luton today and my opinion is that we definitely need a new national narrative to accommodate an increasingly diverse Britain (its irreversible now; white Brits may still be the majority going forward but the country has a huge ethnic population). After the surname map (the website is down from overloading) we need to realize Britain’s assets are her diversity and cosmpolitanism. I like my “hybridity” idea, let’s the best of our host culture here and mix it with the best of our native culture. Its the middle way (and Britain loves the middle way) between multi-culturalism and assimilationism. Also I think all sides need to adopt a measure of flexibility and fluidity; change is the only constant in this increasingly one world.

Brown Punditry and Diversity

My personal thoughts on “superstition” is the following, anything not empirical proved is a belief and all beliefs are acts of faith/superstitions. I respect all to be practised so long as its not imposed on my life in any way (I’m a libertarian dammit) and I try to remain curious/skeptical/openminded about them as long as they seem positive and uplifting.

As for the Astrology issue (Saggitarian, year of the rat if anyone’s curious!) heating up here, I think that’s a good thing that we’re discussing it but it should be done from a perspective on how it impacts Brown Culture. This blog is all about discussing Brownz and understanding the issues but not endlessly and circularly debating them (going indepth in Astrology is going to head to head on whether Partition was right or wrong; that’s not what this blog is about). All beliefs at BrownPundits are subject to scrutiny and investigation however comments that dispute evidential facts become redundant arguments.

I may have my sacred cows, Pakistaniyat, Baha’ism, banking (grasping for more please feel free to add to the list) but when I discuss and submit them here I have to accept that they will reviewed, scrutinized and examined in ways I’m not used to as for instance Omar does from time to time (7yrs ago it used to be the Kolkata Libertarian how times have changed). Its a good things because that’s precisely why we flock to these virtual portals to experience different ideas, mindsets and perspectives that we wouldn’t ordinarily be exposed to.

I wrote a little comical email narrative (fictional) yesterday to our Blasphemy Panel email list and it sort of sums up the prevailing divide in British Asian Muslim (Muzzer) culture. Some of it is obviously an exaggeration (some of it drawn in real life you might recognise me toward the end) but it has some true elements (the British civil service hires many Muslims, even those avowedly not loyal to Britain)

The lioness and her prey.
A short story courtesy of edl/bnp

He is a sorely misunderstood and mild-mannered civil servant whose alter ego is a budding abu hamza, whom he channels for panel discussions and emails rants against secularism. She is a self-confessed liberal extremist who by her own admission can be a feisty witch.

At work he positively intrigues his superiors with his active and growing hobby in designing baggy overalls, refining basic chemicals and collecting high resolution population maps of all major British towns and cities. On their nightly escape to the shires his bosses sigh that if only native Britons were as single minded and disciplined as him they could probably have all the immigrants off work and back on welfare.

After winning a landmark case enshrining the right to hate infidels and foment terror in the EU constitution the prey has been moved to the building’s unmanned cctv control. He passes tea breaks issuing fatwas against various female colleagues who allow the silhouette of their cleavage to cross his peripheral vision. If he’s up to it he might loudly condemn the busty online gals whose websites he stumbles on for a few good hours. He will be sure to give precise descriptions, with no detail spared, of these virtual temptresses to his saturday co-pamphleting ‘bruvas’.

One day in April he shall attend sq & zls upcoming performance ‘Call Me Kafir’. He is so moved by the lead actor, surprisingly zl, that he auditions for ludoo/pipas next performance instead of having a blast with the cast and crew as he had originally intended.

He wins a starring role in their next production and works hard all summer. He realises the prey has become the hero when after a standing ovation as the drunken Devdas he notices in the far corner of the room the lioness with a glint of a tear in her eyes.

Mourning her lost prey she silently moves on to her next kill, a young social spammer who constant blogs about losing friends, ham acting and debate moderation.

This time she will not fail since her slow-moving target is lagging all his new years resolutions spinning out nonsense at all hours of the night to people he’s never met before..

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