June 10, 2015

101 ancient genomes from Bronze Age Eurasia

New data has been posted online. This seems related to this earlier post. Hopefully the study linked to this data will appear soon, but genome bloggers can get to it thanks to the early data release.

Investigation of Bronze Age in Eurasia by sequencing from 101 ancient human remains. 

The Bronze Age (BA) of Eurasia (c. 3,000-1,000 years BC, 3-1 ka BC) was a period of major cultural changes. Earlier hunter-gathering and farming cultures in Europe and Asia were replaced by cultures associated with completely new perceptions and technologies inspired by early urban civilization. It remains debated if these cultural shifts simply represented the circulation of ideas or resulted from large-scale human migrations, potentially also facilitating the spread of Indo-European languages and certain phenotypic traits. To investigate this and the role of BA in the formation of Eurasian genetic structure, we used new methodological improvements to sequence low coverage genomes from 101 ancient humans (19 > 1X average depth) covering 3 ka BC to 600 AD from across Eurasia. We show that around 3 ka BC, Central and Northern Europe and Central Asia receive genetic input through people related to the Yamnaya Culture from the Pontic-Caspian Steppe, resulting in the formation of the Corded Ware Culture in Europe and the Afanasievo Culture in Central Asia. A thousand years later, genetic input from North-Central Europe into Central Asia gives rise to the Sintashta and Andronovo Cultures. During the late BA and Iron Age, the European-derived populations in Asia are gradually replaced by multi-ethnic cultures, of which some relate to contemporary Asian groups, while others share recent ancestry with Native Americans. Our findings are consistent with the hypothesised spread of Indo-European languages during early BA and reveal that major parts of the demographic structure of present-day Eurasian populations were shaped during this period. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency during the BA, contrary to lactose tolerance, indicating a more recent onset of positive selection in the latter than previously believed.

Link

29 comments:

Krefter said...

They got insights with genomes from Bronze age Armenia. I've heard they also got Maikop and ancient Bulgarian genomes.

http://eurogenes.blogspot.com/2015/06/101-ancient-eurasian-genomes.html

I'm sure they learned much more than what is said in the abstract(which basically looks like a repeat of Haak 2015, besides the addition of Central Asia).

ron quiroriano said...

I found this statement very interesting,

"During the late BA and Iron Age, the European-derived populations in Asia are gradually replaced by multi-ethnic cultures, of which some relate to contemporary Asian groups, while others share recent ancestry with Native Americans."

That pretty much confirms what some of us have been saying for a while now,that there have been recent back migrations of Native Americans into Eurasia.

Unknown said...

There is an article about this in the New York Times today, along with another study.
The articles are here (I see through all paywalls):

http://www.nature.com/nature/journal/v522/n7555/full/nature14317.html

http://www.nature.com/nature/journal/v522/n7555/full/nature14507.html

and are veritable cornucopias. Both have mtDNA data and one has copious
Y data. There is de-novo radiocarbon dating.

Interesting: their steppe samples are Y haplogroup R1b.

Pneumatikon said...

I think this will go a long way to clearing up the origin of the Indo-European language. In my opinion this is do or die for the Steppe hypothesis. We already know we Anatolians moved at least into the Caucus mountains. We moved to Iran, too. And if there's no detectible counter-movement from the Steppe to Anatolian then genetically speaking the Steppe hypothesis recedes dramatically in the rear view mirror.

No Migration + No Invasion + No Wheel = No Way.

The linguistics and the archaeology as it stands today already supports every link on the left hand of this equation. The DNA will just make it stronger.

eurologist said...

"We show that around 3 ka BC, Central and Northern Europe and Central Asia receive genetic input through people related to the Yamnaya Culture from the Pontic-Caspian Steppe, resulting in the formation of the Corded Ware Culture in Europe and the Afanasievo Culture in Central Asia."

I have to wait for the details - but I still don't believe this. I have seen no data or study to date that can distinguish the genetic sources of the western Pontic (and surrounding) from that of the Caspian steppe to resolve the cause-and-effect conundrum: that is, did steppe people magically decide they were the better farmers in the wet and cold north, or did instead W Pontic farmers spread both N/ NW fleeing from a major drought into a wetter ares, and N/ NE to further influence and dominate the steppe folks they long new and traded with, there?

Tobus said...

@ron quiroriano: That pretty much confirms what some of us have been saying for a while now,that there have been recent back migrations of Native Americans into Eurasia.

That's an interesting idea, but now that the paper is out (http://www.nature.com/nature/journal/v522/n7555/full/nature14507.html) it doesn't seem to be confirmed. Looking at the ADMIXTURE results the Bronze Age population with the highest Native American at K=5 are the Okunevo, and they have less than MA-1. Moreover, as the ADMIXTURE gets to higher levels (K=7+) most of their initial "Native American" component turns out to be Far East/Siberian - Naganasan, Itelman, Eskimo etc. This is consistent with their "Native American" coming from an MA-1-like ancestor, rather than from recent Native American admixture.

The authors acknowledge this: "Native American-related ancestry in the Okunevo, possibly due to shared ancestry with paleolihic hunter-gatherers from Mal’ta." and I note that they've removed the "recent ancestry with Native Americans" idea from the abstract.

Simon_W said...

@ Eurologist

It can be easily distinguished: Yamnaya folks were a mix of ANE-rich eastern hunter-gatherers + Armenian-like West Asians. Western Pontic farmers on the other hand were basically like other Early European Farmers, that is, a mix of basal Eurasians (Bedouin-like) with western and other hunter-gatherers who lacked ANE.

Simon_W said...

A few observations:

0 out of the 6 Bronze Age Hungarians were R1b. Add to this the Bronze Age Hungarian from Gamba et al. who was J2, then it's 0 out of 7. On the other hand, this new paper has finally found a Corded Ware male carrying R1b. He was earlier than all the German Bell Beakers with R1b. I think it's time to call the narrative that large masses of Yamnaya-derived R1b people migrated up the Danube into question. (R1b dominance was the result of founder effects anyway.)

But also the idea that the Bell Beaker culture was everywhere dominated by R1b: One of the Remedello males from Northern Italy definitely postdates the Bell Beaker period, and he's still I2.

The finding of J2a in the Iron Age Altai shows that, contrary to what the authors write, after Andronovo it wasn't only East Asians who migrated to central Asia, but also West Asians. And therefore I'm not sure that Tocharian comes from Afanasievo, and not from a West Asian IE population.

The relationship of Sintashta with the EEF admixed Corded people is fascinating.

Lastly, I want to mention that one of the Iron Age Armenians has been uploaded to GEDmatch (Kit No. M691697). I analysed it with the Eurogenes K15 calculator, and the best matching oracle results are intriguing:
# Primary Population (source) Secondary Population (source) Distance
1 82.8% Chechen + 17.2% East_German @ 7.38
2 83% Chechen + 17% Ukrainian_Lviv @ 7.5
3 85% Chechen + 15% Swedish @ 7.51
4 83.2% Chechen + 16.8% South_Polish @ 7.51
5 84.2% Chechen + 15.8% Polish @ 7.59

Seems like Iron Age Armenians had some substantial northern admixture!

Gioiello said...

"That's an interesting and quite controversial theory. But I have to disagree, it's rather not a founder effect. Bell Beakers seem to be uniformly R1b and that's the source of most of modern U106 and P312. CWC in Western Europe was mostly replaced, it's recapitulation is visible just in Frisian/coastal CTS4385/L664, Z283* (Swiss CWC?), Z282*, some Z280(S24902?, Z280*). They are absolutely minor now. One R1b doesn't change anything, look at the patterns and archeology".
(Arthur Martyka, answering a post of mine where I quoted Kefter and Davidski from Eurogenes blog, in Human Population Genetics, FB Group).
It's time. I won my battle.

Ryan said...

"Moreover, as the ADMIXTURE gets to higher levels (K=7+) most of their initial "Native American" component turns out to be Far East/Siberian - Naganasan, Itelman, Eskimo etc"

Inuit (Eskimo) people are Native Americans too FYI. Recent Inuit or Paleoeskimo admixture would still be recent Native American admixture. Or at least, Reich has them as 57% Native American + 43% East Asian.

This shouldn't be surprising though. There are mitchondrial DNA haplogtypes scattered in a few groups in northern and eastern Siberia that have a pretty clear Native American origin.

AWood said...

@Simon_W

0/6 BA Hungarians isn't a true statistic. Only three of these are actually male, the other three female.

The lack of R1b among 3 men shouldn't really come as a surprise as Hungary had been populated by earlier hunter gatherers and neolithic people from the mid east. I2 and G2 have been found at Neolithic and earlier sites of Europe. They didn't suddenly vanish as these sample groups are found in the same region today. I believe one is I2-M223 which is common in central European populations today and was also found in neolithic Spain from Haak 2015.

Simon_W said...

RISE423, an Armenian from the late Bronze Age (M930063 on GEDmatch) has even more north European-like admixture, judging from his Eurogenes K15 results. In the oracle his best approximations are:
1 75% Georgian + 25% North_German @ 7.73
2 76.7% Georgian + 23.3% West_Scottish @ 7.75
3 76.2% Georgian + 23.8% Danish @ 7.76

I think this means that the Armenian language and probably also their R1b-L23 came with steppe admixed north European-like people.

Gary Moore said...

There is a good case that the spread of Indo-European in Europe may be associated with YHG Q. Regions of peak YHG Q concentration in Europe correlate well with Hallstatt and Nordic Bronze Age cultures. As noted previously, bulk DNA testing has turned up some surprisingly close matches between European and Native American men with YHG Q. Because YHG Q is not that old and the shared subclades are even younger, links between European and North American populations probably postdate the glacial era.

As noted previously in these blogs, there are also striking correlations between Indo-European and and North American languages of the hypothetical Macro-Siouan family. For instance, the form for 'eye':

Cherokee (Iro) agadoli / agatoli / akta
Mingo (Iro) kaka a’
*PIE *h₃okʷ-, *h₃ekʷ-
Hittite sākuwa, saguwa-
Pawnee kíriiku’
Toch A ak
Mod. Arm ačk’
Avestan čama, čašman-, chashman
Old Persian čaša-, čašna
Vedic Sanskrit ákṣi, cháksus
Old Prussian ackis

Mohawk (Iro) okà:ra
Oneida (Iro) okáh(la)
Anc Grk ophthalmós
Old Church Slavonic oko
Old Norse auga
Swedish öga
Latin oculus

The initial 'a-' and 'o-' in the Iroquoian forms are pronominal prefixes and vary by person/number in the modern languages. In IE, they appear to be frozen in the 3PS form. Such fossilized prefixes have been noted in Basque, and IE seems to have them too.

So far, skeptics can shrug these resemblances off as coincidence, but things get interesting when you compare Siouan forms for 'eye':

Lakota ištá
Crow ishtá

No, they are not the same, but they do correlate with the Hittite forms for 'ear': istāman, istam-an- ~ istam-in-.

The Hittite form is a bit of a mystery: "The root was lost in IE (connections with Ancient Greek and Avestan forms with the invariant meaning 'an organ of perception' or 'a hole in the head' are semantically unsatisfactory). ..." (http://starling.rinet.ru/new100/ana.pdf)

Hamar Fox said...

Tobus,

That's an interesting idea, but now that the paper is out (http://www.nature.com/nature/journal/v522/n7555/full/nature14507.html) it doesn't seem to be confirmed. Looking at the ADMIXTURE results the Bronze Age population with the highest Native American at K=5 are the Okunevo, and they have less than MA-1. Moreover, as the ADMIXTURE gets to higher levels (K=7+) most of their initial "Native American" component turns out to be Far East/Siberian - Naganasan, Itelman, Eskimo etc. This is consistent with their "Native American" coming from an MA-1-like ancestor, rather than from recent Native American admixture."

I'm always baffled at how even professionals can be so confused by ADMIXTURE. It's really obvious to me that, because ADMIXTURE incorrectly identifies Amerindians as 100% East Asian (at K=3), even though MA-1 is a constituent part of Amerindians and is not 100% East Asian at K=3, it follows that ADMIXTURE will confuse Amerindian-like signatures in populations closely related to MA-1 as fundamentally 'East Asian', which is exactly what we see. Populations that appear 'East Asian admixed' at K=3, even though we can strongly suspect that they are not (or at least not as significantly) East Asian admixed, all have their 'East Asian' component resolve completely into the Amerindian component at K=4.

The error is obvious. Amerind scores at K=4 and above have an 'East Asian' basis at K=3 and therefore appear 'legit', even though anyone who's followed papers on ancient DNA over the past few years should be able to figure out the reason for this. Even Lazaridis and such have made errors in their interpretations of their ADMIXTURE results (mostly in not questioning why Amerindians are not recognised as admixed, and factoring this error of ADMIXTURE into their interpretation of other results at lower K's). No wonder anthro boards are as moronic as they are when even professionals make blunders of this magnitude.



Nirjhar007 said...

Gary, I'm awaiting for your full paper, when its going to be completed?.

Tobus said...

@Ryan: Inuit (Eskimo) people are Native Americans too FYI.

Technically (and legally!) yes, they are "native" to the Americas in the sense that they were present when Columbus arrived, but genetically and historically they are very different to non-Arctic Native Americans like Karitiana, Mixe and Cree.

According to Wikipedia the Inuit migrated into America from Siberia in the last 1500 years, replacing Paleo-Eskimo cultures that had migrated from Siberia over the last 5000 years. At low K levels they are a mix of archetypical East Asian (Han) and Native American (Karitiana) DNA, but you can see from the higher ADMIXTURE levels in this paper (eg K=7-20), as well as formal stats in other papers, that they have a great deal more in common with Siberians than with Americans and that their closest Siberian relatives lack any significant American DNA. This is much more consistent with Siberians migrating into America and picking up some American DNA, than with Native Americans migrating into Siberia and picking up some non-American DNA.

As with any admixture event there is probably some degree of gene flow both ways, but it doesn't look like much Karitiana, Mixe or Cree got passed back into Siberia, and certainly not at levels that would indicate migration.

eurologist said...

"It can be easily distinguished: Yamnaya folks were a mix of ANE-rich eastern hunter-gatherers + Armenian-like West Asians. Western Pontic farmers on the other hand were basically like other Early European Farmers, that is, a mix of basal Eurasians (Bedouin-like) with western and other hunter-gatherers who lacked ANE."

Simon_W,

Are there autosomal studies of the Western Pontic in the appropriate time frame in this work, or others?

Nirjhar007 said...

Palisto has done some analysis on Armenian Samples-
http://kurdishdna.blogspot.in/2015/06/dodecad-k12b-values-of-bronze-age.html

capra internetensis said...

@Tobus

I think the Siberian Yupik are generally considered to have crossed the Bering Strait from Alaska, but their genetic influence is pretty well limited to the Russian Far East. You do find the occasional Q-M3 in Chukchis and such, I believe.

Gary Moore said...

@Nirjhar007 -

I've got a massive amount of material that I have to organize in order to publish. I want to publish in a peer-reviewed journal, but I really need a collaborator with serious credentials in historical linguistics. There is simply too much for me to do by myself, and it is imperative to carefully edit and cross check any submissions to a professional journal, particularly in this field where even minor errors in transcription can cause an author to lose all credibility. I've tried contacting authorities such as Donald Ringe, David Anthony, and Andrew Garret at UC Berkley to get some feedback on my data, but they have not bothered to reply. One IE linguist who did get back to me wrote: "I am not very impressed by these sorts of data, and few if any historical linguists would be. ..." but went on to admit he had not given much thought to why so many anatomical terms in Greek and Latin began in 'o-' (that is, the Iroquoian third person singular 'inalienable' prefix). Currently, I am in a "career hiatus" and find myself spending most of my time trying to line up a new contract.

@Tobus, capra internetensis, Ryan -

C.C. Uhlenbeck proposed a link between Eskimo and Indo-European languages. I personally think that the evidence is not as strong as a link between the North American Iroquoian and Siouan languages. See http://id.erudit.org/revue/etudinuit/2008/v32/n2/038217ar.pdf

In earlier postings, I noted the striking correlations between forms for 'dog, horse' in Indo-European and the Siouan-Iroquoian-Caddoan languages (e.g. Russian suka, Lakota šų́nka). Compare with Eskimo-Aleut forms for 'dog':


qimmiq (Most inuit dialects including Inupiaq, Inuvialuktun, Inuktitut)
qipmiq (Malimiutun inupiaq)
qinmiq (Inuinnaqtun)
qingmiq (Natsilingmiutut/Kivalliq)
kimmik (Labrador Inuttut)
qimmeq (Kalaallisut)
sabaakax (Aleut)
qikmiq (Siberian Yupik)
qimugta/piguta (Yup'ik)

Note that Aleut form appears to display a similar sound pattern to IE and SIC forms, with the addition of a couple of elements: sa + (baa) + ka + (x). This form suggests a bridge between the common North American and IE forms.

German Dziebel said...

@Hamar Fox

"I'm always baffled at how even professionals can be so confused by ADMIXTURE. It's really obvious to me that, because ADMIXTURE incorrectly identifies Amerindians as 100% East Asian (at K=3), even though MA-1 is a constituent part of Amerindians and is not 100% East Asian at K=3, it follows that ADMIXTURE will confuse Amerindian-like signatures in populations closely related to MA-1 as fundamentally 'East Asian', which is exactly what we see. Populations that appear 'East Asian admixed' at K=3, even though we can strongly suspect that they are not (or at least not as significantly) East Asian admixed, all have their 'East Asian' component resolve completely into the Amerindian component at K=4."

There's indeed confusion but of a different nature. It's pretty clear to everyone without a bias that the pseudo-East Asian component is in fact an Amerindian component (Karitiana is unadmixed on all the levels from K=2 on but for some reason the color of its component changes, which is the source of the confusion), which splits into a true East Asian component and a West Eurasian component at higher K levels. If you replace YELLOW at K=2 with the Karitiana one (GREY) from K=4 and keep Karitiana the same color all the way up (just like San are on the African side), you'll get a correct picture.

Nirjhar007 said...

Gary,
Have you tried this fella?
http://jdbengt.net/

Gioiello said...

Nirjhar007, to try to demonstrate that Indo-European languages expanded with hg. Q and that they have a link with Amerindian languages does mean not understanding anything both of linguistics and genetics. You know I am a friend of yours, but I have to be frank. The link are very old, at the Nostratic level, but those words your friend published aren't worth anything. Words for "dog" are similar in all Eurasia and very likely are Wanderwoerter. One word [sabaakax (Aleut)] was similar to Russian "sobaka" and very likely came to Russian from Siberia. I wrote a paper (unpublished) 40 years ago where I thought having demonstrated a link of the IE word for "6" and the Sino-Tibetan one, but only because IE and ST derive from some old languages which were very likely close in Central Asia at some time, and there are astonishing papers about this link now. Of course any professional linguist would accept working on that.

Hamar Fox said...

German Dziebel,


There's indeed confusion but of a different nature.

There are two problems that recur in all of the published ADMIXTURE results of ancient genomes (in a modern context) that I've seen:

1) ADMIXTURE mistakes Amerindians as wholly East Eurasian at low K-levels, and therefore gives faulty estimates of East Eurasian admixture in ancient Eurasians at low K-levels. This is because the West Eurasian signatures in Amerindians are wrongly considered to be East Eurasian, and therefore West Eurasians with similar signals are also considered to be part East Eurasian in the same proportion as their genetic material resembles the West Eurasian material in Amerindians.

2) Amerindians are wrongly identified very early on (K=4) as an ancestral population, even though they are derived. Therefore, ADMIXTURE wrongly identifies old world populations with ANE (or to a lesser extent WHG) and/or North East Eurasian ties to be highly 'Amerindian-admixed'. That is, old world populations with genetic signatures that resemble at least one of the following: 1)The West Eurasian populations that contributed to the make-up of modern Amerindians; or, 2) The East Eurasian populations that contributed to the make-up of modern Amerindians.



The second error explains the farce that features in the paper's abstract. While the supplementary information correctly identifies the more likely cause of heightened 'Amerindian' affinities of certain old world populations in ADMIXTURE, the abstract features only the less likely explanation, which I find absurd -- unless I'm missing some additional evidence that they employed in reaching their abstract's conclusion.

It's pretty clear to everyone without a bias that the pseudo-East Asian component is in fact an Amerindian component (Karitiana is unadmixed on all the levels from K=2 on but for some reason the color of its component changes, which is the source of the confusion), which splits into a true East Asian component and a West Eurasian component at higher K levels. If you replace YELLOW at K=2 with the Karitiana one (GREY) from K=4 and keep Karitiana the same color all the way up (just like San are on the African side), you'll get a correct picture.

Our differences in interpretation aside, I think we'd both like to see these results presented without an Amerindian reference sample, for the sake of contrast, since no population confuses ADMXITURE as much as Amerindians seem to.

Simon_W said...

@ Awood

There are four Bronze Age Hungarian y-chromosomes in this paper:

RISE254 Vatya culture, about 2000 BC = I2
RISE247 Vatya culture, somewhat after 1700 BC = I2a
RISE479 Vatya culture, without date = I2
RISE374 Maros culture, somewhat after 1750 BC = G2a

And the one from Gamba et al. was:

BR2 Kyjatice culture, about 1200 BC = J2a

The Maros culture belonged to the syncretistic cultures with late Bell Beaker influence, but not to Bell Beaker proper.

The Kyjatice culture belonged to the Southeast group of the Urnfield cultures.

Indeed, this evidence doesn't rule out that there was also R1b in Bronze Age Hungary. But it was far from predominant, that much can be said.


@ Eurologist

No, there's nothing from the Western Pontic so far.

However, initially there must have been an early Farmer (EEF) population similar to Starcevo, what else? Later possibly people from the steppe with eastern hunter-gatherer (EHG) ancestry migrated to the western Pontic, that would be in line with Anthony's theory. In any case the original elements, EEF and EHG, but also the admixed Yamnaya type ancestry were all very distinct from each other, there's no chance to confound them. Archeology and evidence from mtDNA suggest that EEF people moved eastwards into the steppe, but no further than the Dneper and the lower Don. And indeed, autosomal evidence from Yamnaya people east of the Dneper and Don show no evidence of EEF admixture.

Simon_W said...

What regards these Bronze Age Armenians, the Eurogenes K15 oracle may be misleading, because their ancestry doesn't fit into the clusters defined on modern people.

In any case their Dodecad K12b values for the North_European component are very close to those of North Caucasian populations, like the Chechens. But it's peculiar that the Georgians, who at least now live north of these Bronze Age Armenians, have much less of the North_European component. In the detailed PCA on Eurogenes the Bronze Age Armenians are closest to central North Caucasian people like the Balkars and the North Ossetians. One individual is closest to the Lezgins and Chechens in the Northeast Caucasus. So maybe in the Bronze Age there was a homogenous population from Armenia to the central-North and Northeastern Caucasus, and the Kartvelians moved in later, perhaps from the west.

But it's also interesting that the one individual that was labeled „Iron Age“ Armenian has a slight shift towards the Balkans, in the Eurogenes PCA. If he's really later than the other, the „Bronze Age“ Armenians, this would be evidence for a Balkan origin of the Armenian language.

terryt said...

"no population confuses ADMXITURE as much as Amerindians seem to".

Sums the situation up very well.

German Dziebel said...

@Hamar Fox

"That is, old world populations with genetic signatures that resemble at least one of the following: 1)The West Eurasian populations that contributed to the make-up of modern Amerindians; or, 2) The East Eurasian populations that contributed to the make-up of modern Amerindians."

All of West Eurasians are "Amerindian-shifted" compared to East Eurasians. And all East Eurasians are Amerindian-shifted compared to West Eurasians. If Amerindians were an admixed population, we would've seen only a subset of East Eurasians and a subset of West Eurasians as Amerindian shifted. The geographic depth of Amerindian penetration into both West and East Eurasia, which is confirmed by all ancient DNA results (Tianyuan, Ust-Isim, MA-1, La Brana, Kostenki), is not compatible with a West Eurasian-East Eurasian admixture in the New World. The opposite, however, is a matter of course. Also, an admixture between two heterozygous populations such as West Eurasians and East Eurasians is not compatible with the high homozygosity of Amerindian populations coupled with very clear unique genetic signatures of Amerindians missing from either West Eurasians and East Eurasians..

"I think we'd both like to see these results presented without an Amerindian reference sample, for the sake of contrast, since no population confuses ADMXITURE as much as Amerindians seem to."

I'd also like to see a worldwide ADMIXTURE run without Africans, who I think are heavily archaic admixed and didn't contribute to modern human diversity outside of Africa until the slave trade times.

Tobus said...

@German:
All of West Eurasians are "Amerindian-shifted" compared to East Eurasians. And all East Eurasians are Amerindian-shifted compared to West Eurasians.

In fairness, you could equally say that all Amerindians are "European-shifted" compared to East Eurasians, and all Amerindians are "East Asian-shifted" compared to Europeans.

If Amerindians were an admixed population, we would've seen only a subset of East Eurasians and a subset of West Eurasians as Amerindian shifted.

Quite the contrary - the population receiving the DNA will be shifted toward *all* of the incoming lineage and its close relatives, even ancient ones before the admixture happened. Conversely the population giving the DNA will *not* be shifted towards ancestors/relatives of the receiving population. If the geneflow went Euro->Nam then Amerindians will be drawn closer to all Europeans, but if it went NAm->Euro then only Europeans downstream from the admixture will show an Amerindian affinity. The relative Amerindian affinities of K14, UI and MA-1 are consistent with the first scenario and effectively rule out the second one.

The geographic depth of Amerindian penetration into both West and East Eurasia which is confirmed by all ancient DNA results (Tianyuan, Ust-Isim, MA-1, La Brana, Kostenki)

This is part of the ADMIXTURE confusion discussed above - when you see multiple components in ancient samples (like UI/MA-1 etc.) this does *not* mean that these components contributed to the ancient, it instead means that the ancient contributed to these components... time goes forwards remember, and the modern components didn't actually exist at the time of the ancients they are being projected onto. There's no way that the "Sardinian" in UI or the "Karitiana" in MA-1 can actually *be* from Sardinian or Karitiana populations as neither population existed at the time! The correct interpretation is that the modern (Sardinian/Karitiana) component harbours some ancient (UI/MA-1)-related ancestry. Try thinking of the ancients on ADMIXTURE as potential *sources* of the components, with moderns being the various destinations.