Consequences of Damgaard et al. 2018 (I): EHG ancestry in Maykop samples, and the potential Anatolian expansion routes

neolithic_steppe-anatolian-migrations

This is part I of two posts on the most recent data concerning the earliest known Indo-European migrations.

Anatolian in Armi

I am reading in forums about “Kroonen’s proposal” of Anatolian in the 3rd millennium. That is false. The Copenhagen group (in particular the authors of the linguistic supplement, Kroonen, Barjamovic, and Peyrot) are merely referencing Archi (2011. “In Search of Armi”. Journal of Cuneiform Studies 63: 5–34) in turn using transcriptions from Bonechi (1990. “Aleppo in età arcaica; a proposito di un’opera recente”. Studi Epigrafici e Linguistici sul Vicino Oriente Antico 7: 15–37.), who asserted the potential Anatolian origin of the terms. This is what Archi had to say about this:

Most of these personal names belong to a name-giving tradition different from that of Ebla; Arra-ti/tulu(m) is attested also at Dulu, a neighbouring city-state (Bonechi 1990b: 22–25).28 We must, therefore, deduce that Armi belonged to a marginal, partially Semitized linguistic area different from the ethno-linguistic region dominated by Ebla. Typical are masculine personal names ending in -a-du: A-la/li-wa-du/da, A-li/lu-wa-du, Ba-mi-a-du, La-wadu, Mi-mi-a-du, Mu-lu-wa-du. This reminds one of the suffix -(a)nda, -(a)ndu, very productive in the Anatolian branch of Indo-European (Laroche 1966: 329). Elements such as ali-, alali-, lawadu-, memi-, mula/i- are attested in Anatolian personal names of the Old Assyrian period (Laroche 1966: 26–27, 106, 118, 120).

First_Eblaite_Empire
Ebla’ first kingdom at its height c. 2340 BC. Hipothetical location of Armi depicted. The first Eblaite kingdom extended from Urshu in the north,1 to Damascus area in the south.2 And from Phoenicia and the coastal mountains in the west,3 4 to Tuttul,5 and Haddu in the east.6 The eastern kingdom of Nagar controlled most of the Khabur basin from the river junction with the Euphrates to the northwestern part at Nabada.7 Page 101. From Wikipedia.

This was used by Archi to speculatively locate the state of Armi, in or near Ebla territory, which could correspond with the region of modern north-western Syria:

The onomastic tradition of Armi, so different from that of Ebla and her allies (§ 5), obliges us to locate this city on the edges of the Semitized area and, thus, necessarily north of the line running through Hassuwan – Ursaum – Irritum – Harran. If Armi were to be found at Banat-Bazi, it would have represented an anomaly within an otherwise homogenous linguistic scenario.34

Taken as a whole, the available information suggests that Armi was a regional state, which enjoyed a privileged relationship with Ebla: the exchange of goods between the two cities was comparable only to that between Ebla and Mari. No other state sent so many people to Ebla, especially merchants, lú-kar. It is only a hypothesis that Armi was the go-between for Ebla and for the areas where silver and copper were extracted.

This proposal is similar to the one used to support Indo-Aryan terminology in Mittanni (ca. 16th-14th c. BC), so the scarce material should not pose a problem to those previously arguing about the ‘oldest’ nature of Indo-Aryan.

NOTE. On the other hand, the theory connecting ‘mariannu‘, a term dated to 1761 BC (referenced also in the linguistic supplement), and put in relation with PIIr. *arya, seems too hypothetical for the moment, although there is a clear expansion of Aryan-related terms in the Middle East that could support one or more relevant eastern migration waves of Indo-Aryans from Asia.

Potential routes of Anatolian migration

Once we have accepted that Anatolian is not Late PIE – and that only needed a study of Anatolian archaisms, not the terminology from Armi – , we can move on to explore the potential routes of expansion.

On the Balkan route

A current sketch of the dots connecting Khvalynsk with Anatolia is as follows.

suvorovo-scepters
1—39 — sceptre bearers of the type Giurgiuleşti and Suvorovo; 40—60 — Gumelniţa-Varna-Bolgrad-Aldeni cultural sphere; 61 — Fălciu; 62 — Cainari; 63 — Giurgiuleşti; 64 — Suvorovo; 65 — Casimcea; 66 — Kjulevča; 67 — Reka Devnja; 68 — Drama; 69 — Gonova Mogila; 70 — Reževo.

First, we have the early expansion of Suvorovo chieftains spreading from ca. 4400-4000 BC in the lower Danube region, related to Novodanilovka chiefs of the North Pontic region, and both in turn related to Khvalynsk horse riders (read a a recent detailed post on this question).

Then we have Cernavoda I (ca. 3850-3550 BC), a culture potentially derived from the earlier expansion of Suvorovo chiefs, as shown in cultural similarities with preceding cultures and Yamna, and also in the contacts with the North Pontic steppe cultures (read a a recent detailed post on this question).

We also have proof of genetic inflow from the steppe into populations of cultures near those suggested to be heirs of those dominated by Suvorovo chiefs, from the 5th millennium BC (in Varna I ca. 4630 BC, and Smyadovo ca. 4500 BC, see image below).

If these neighbouring Balkan peoples of ca. 4500 BC are taken as proxies for Proto-Anatolians, then it becomes quite clear why Old Hittite samples dated 3,000 years after this migration event of elite chiefs could show no or almost no ancestry from Europe (for this question, read my revision of Lazaridis’ preprint).

NOTE. A full account of the crisis in the lower Danube, as well as the Suvorovo-Novodanilovka intrusion, is available in Anthony (2007).

mathieson-2018-balkan-expansion
Modified image, including PCA and supervised ADMIXTURE data from Mathieson et al. (2018). Blue arrow represents incoming ancestry from Suvorovo chiefs, red line represents distance from the majority of the neighbouring Balkan population in this period studied to date. Northwestern-Anatolian Neolithic (grey), Yamnaya from Samara (yellow), EHG (pink) and WHG (green).

The southern Balkans and Anatolia

The later connection of Cernavoda II-III and related cultures (and potentially Ezero) with Troy, on the other hand, is still blurry. But, even if a massive migration of Common Anatolian is found to happen from the Balkans into Anatolia in the late 4th / beginning of the 3rd millennium, the people responsible for this expansion could show a minimal trace of European ancestry.

A new paper has appeared recently (in Russian), Dubene and Troy: Gold and Prosperity in the Third Millennium Cal. BCE in Eurasia. Stratum Plus, 2 (2018), by L. Nikolova, showing commercial contacts between Troy and cultures from Bulgaria:

Earlier third millennium cal BCE is the period of development of interconnected Early Bronze Age societies in Eurasia, which economic and social structures expressed variants of pre-state political structures, named in the specialized literature tribes and chiefdoms. In this work new arguments will be added to the chiefdom model of third millennium cal BC societies of Yunatsite culture in the Central Balkans from the perspectives of the interrelations between Dubene (south central Bulgaria) and Troy (northwest Turkey) wealth expression.

Possible explanations of the similarity in the wealth expression between Troy and Yunatsite chiefdoms is the direct interaction between the political elite. However, the golden and silver objects in the third millennium cal BCE in the Eastern Mediterranean are most of all an expression of economic wealth. This is the biggest difference between the early state and chiefdoms in the third millennium cal BCE in Eurasia and Africa. The literacy and the wealth expression in the early states was politically centralized, while the absence of literacy and wider distribution of the wealth expression in the chiefdoms of the eastern Mediterranean are indicators, that wider distribution of wealth and the existed stable subsistence layers prevented the formation of states and the need to regulate the political systems through literacy.

The only way to link Common Anatolians to their Proto-Anatolian (linguistic) ancestors would therefore be to study preceding cultures and their expansions, until a proper connecting route is found, as I said recently.

These late commercial contacts in the south-eastern Balkans (Nikolova also offers a simplified presentation of data, in English) are yet another proof of how Common Anatolian languages may have further expanded into Anatolia.

NOTE. One should also take into account the distribution of modern R1b-M269* and L23* subclades (i.e. those not belonging to the most common subclades expanding with Yamna), which seem to peak around the Balkans. While those may just belong to founder effects of populations preceding Suvorovo or related to Yamna migrants, the Balkans is a region known to have retained Y-DNA haplogroup diversity, in contrast with other European regions.

On a purely linguistic aspect, there are strong Hattic and Hurrian influences on Anatolian languages, representing a unique layer that clearly differentiates them from LPIE languages, pointing also to different substrates behind each attested Common Anatolian branch or individual language:

  • Phonetic changes, like the appearance of /f/ and /v/.
  • Split ergativity: Hurrian is ergative, Hattic probably too.
  • Increasing use of enclitic pronoun and particle chains after first stressed word: in Hattic after verb, in Hurrian after nominal forms.
  • Almost obligatory use of clause initial and enclitic connectors: e.g. semantic and syntactic identity of Hattic pala/bala and Hittite nu.

NOTE. For a superficial discussion of this, see e.g. An Indo-European Linguistic Area and its Characteristics: Ancient Anatolia. Areal Diffusion as a Challenge to the Comparative Method?, by Calvert Watkins. You can also search for any of the mentioned shared isoglosses between Middle Eastern languages and Anatolian if you want more details.

On the Caucasus route

It seems that the Danish group is now taking a stance in favour of a Maykop route (from the linguistic supplement):

The period of Proto-Anatolian linguistic unity can now be placed in the 4th millennium BCE and may have been contemporaneous with e.g. the Maykop culture (3700–3000 BCE), which influenced the formation and apparent westward migration of the Yamnaya and maintained commercial and cultural contact with the Anatolian highlands (Kristiansen et al. 2018).

In fact, they have data to support this:

The EHG ancestry detected in individuals associated with both Yamnaya (3000–2400 BCE) and the Maykop culture (3700–3000 BCE) (in prep.) is absent from our Anatolian specimens, suggesting that neither archaeological horizon constitutes a suitable candidate for a “homeland” or “stepping stone” for the origin or spread of Anatolian Indo- European speakers to Anatolia. However, with the archaeological and genetic data presented here, we cannot reject a continuous small-scale influx of mixed groups from the direction of the Caucasus during the Chalcolithic period of the 4th millennium BCE.

While it is difficult to speak about the consequences of this find without having access to this paper in preparation or its samples, we already knew that Maykop had obvious cultural contacts with the steppe.

It will not be surprising to find not only EHG, but also R1b-L23 subclades there. In my opinion, though, the most likely source of EHG ancestry in Maykop (given the different culture shown in other steppe groups) is exogamy.

The question will still remain: was this a Proto-Anatolian-speaking group?

eneolithic_steppe
Diachronic map of Eneolithic migrations ca. 4000-3100 BC

My opinion in this regard – again, without access to the study – is that you would still need to propose:

  • A break-up of Anatolian ca. 4500 BC represented by some early group migrating into the Northern Caucasus area.
  • For this group – who were closely related linguistically and culturally to early Khvalynsk – to remain isolated in or around the Northern Caucasus, i.e. somehow ‘hidden’ from the evolving LPIE speakers in late Khvalynsk/early Yamna peoples.
  • Then, they would need to have migrated from Maykop to Anatolian territory only after ca. 3700 BC – while having close commercial contacts with Khvalynsk and the North Pontic cultures in the period 3700-3000 BC -, in some migration wave that has not showed up in the archaeological records to date.
  • Then appear as Old Hittites without showing EHG ancestry (even though they show it in the period 3700-3000 BC), near the region of the Armi state, where Anatolian was supposedly spoken already in the mid-3rd millennium.

Not a very convincing picture, right now, but indeed possible.

Also, we have R1b-Z2103 lineages and clear steppe ancestry in the region probably ca. 2500 BC with Hajji Firuz, which is most likely the product of the late Khvalynsk migration waves that we are seeing in the recent papers.

These migrations are then related to early LPIE-speaking migrants spreading after ca. 3300 BC – that also caused the formation of early Yamna and the expansion of Tocharian-related migrants – , which leaves almost no space for an Anatolian expansion, unless one supports that the former drove the latter.

NOTE. In any case, if the Caucasus route turned out to be the actual Anatolian route, I guess this would be a way as good as any other to finally kill their Indo-European – Corded Ware theory, for obvious reasons.

On the North Iranian homeland

A few thoughts for those equating CHG ancestry in IE speakers (and especially now in Old Hittites) with an origin in North Iran, due to a recent comment by David Reich:

In the paper it is clearly stated that there is no Neolithic Iranian ancestry in the Old Hittite samples.

Ancestry is not people, and it is certainly not language. The addition of CHG ancestry to the Eneolithic steppe need not mean a population or linguistic replacement. Although it could have been. But this has to be demonstrated with solid anthropological models.

NOTE. On the other hand, if you find people who considered (at least until de Barros Damgaard et al. 2018) steppe (ancestry/PCA) = Indo-European, then you should probably confront them about why CHG in Hittites and the arrival of CHG in steppe groups is now not to be considered the same, i.e why CHG / Iran_N ≠ PIE.

Since there has been no serious North Iranian homeland proposal made for a while, it is difficult to delineate a modern sketch, and I won’t spend the time with that unless there is some real anthropological model and genetic proof of it. I guess the Armenian homeland hypothesis proposed by Gamkrelidze and Ivanov (1995) would do, but since it relies on outdated data (some of which appears also in Gimbutas’ writings), it would need a full revision.

NOTE. Their theory of glottalic consonants (or ejectives) relied on the ‘archaism’ of Hittite, Germanic, and Armenian. As you can see (unless you live in the mid-20th century) this is not very reasonable, since Hittite is attested quite late and after heavy admixture with Middle Eastern peoples, and Germanic and Armenian are some of the latest attested (and more admixed, phonetically changed) languages.

This would be a proper answer, indeed, for those who would accept this homeland due to the reconstruction of ‘ejectives’ for these languages. Evidently, there is no need to posit a homeland near Armenia to propose a glottalic theory. Kortlandt is a proponent of a late and small expansion of Late PIE from the steppe, and still proposes a reconstruction of ejectives for PIE. But, this was the main reason of Gamkrelidze and Ivanov to propose that homeland, and in that sense it is obviously flawed.

Those claiming a relationship of the North Iranian homeland with such EHG ancestry in Maykop, or with the hypothetic Proto-Euphratic or Gutian, are obviously not understanding the implications of finding steppe ancestry coupled with (likely) early Late PIE migrants in the region in the mid-4th millennium.

Related:

No large-scale steppe migration into Anatolia; early Yamna migrations and MLBA brought LPIE dialects in Asia

eurasian-hittite-samples

Another, simultaneous paper with the Eurasian samples from Nature, The first horse herders and the impact of early Bronze Age steppe expansions into Asia, by de Barros Damgaard et al., Science (2018).

A lot of interesting data, I will try to analyse its main implications, if only superficially, in sections.

Anatolian samples

Anatolia_EBA from Ovaören, and Anatolia_MLBA (this including Assyrian and Old Hittite samples), all from Kalehöyük, show almost no change in Y-DNA lineages (three samples J2a, one G2a), and therefore an origin of these people in common with CHG and Iranian Neolithic populations is likely. No EHG ancestry is found. And PCA cluster is just somehow closer to Europe, but not to EHG populations.

NOTE. Hittite is attested only in the late first half of the 2nd millennium, although the authors cite (in the linguistic supplement) potential evidence from the palatial archives of the ancient city of Ebla in Syria to argue that Indo-European languages may have been already spoken in the region in the late 3rd millennium BCE.

Regarding the Assyrian samples (one J2a) from Ovaören:

Layer V of GT-137 was the richest in terms of architectural finds and dates to the Early Bronze Age II. In this layer, 2 different structures and a well were uncovered. The well was filled with stones, pottery, and human skeletons (Figs. S2 and S3). In total, skeletons belonging to 22 individuals, including adults, young adults, and children, must belong to the disturbed Early Bronze Age II graves adjacent to the well (103). Pottery and stones found below the skeletons demonstrate that the water well was consciously filled and closed. The fill consists of dumped stones, sherds and skeletons, and the closing stones demonstrate that the water well was consciously filled and cancelled.

Regarding the site most likely associated with the emergence of Old Hittite (two samples J2a1, one G2a2b1), this is what we know:

The Middle Bronze Age at Kaman-Kalehöyük represented by stratum IIIc yields material remains (seals and ceramics) contemporary with the international trade system managed by expatriate Assyrian merchants evidenced at the nearby site of Kültepe/Kanesh. It is therefore also referred to as belonging to the “Assyrian Colony Period” (98). The stratum has revealed three burned architectural units, and it has been suggested that the seemingly site-wide conflagration might be connected to a destruction event linked with the emergence of the Old Hittite state (99). (…) Omura (100) suggests that the rooms could belong to a public building, and that it might even be a small trade center based on the types of artifacts recovered. Omura (100) has concluded that the evidence from the first complex indicates a battle between 2 groups took place at the site. It is possible that a group died inside the buildings, mostly perishing in the fire, while another group died in the courtyard.

NOTE. For more on the Old Hittite period, you can read this for example.

Regarding PCA:

The PCA (Fig. 2B) indicates that all the Anatolian genome sequences from the Early Bronze Age ( -2200 BCE) and Late Bronze Age (-1600 BCE) cluster with a previously sequenced Copper Age ( -3900- 3700 BCE) individual from Northwestern Anatolia and lie between Anatolian Neolithic (Anatolia_ N) samples and CHG samples but not between Anatolia_N and EHG samples.

(…) we are not able to reject a two-population qpAdm model in which these groups derive -60% of their ancestry from Anatolian farmers and -40% from CHG-related ancestry (p-value = 0.5). This signal is not driven by Neolithic Iranian ancestry.

pca-ancient-modern-eurasians
Principal Component Analysis estimated with ancient and modern Eurasians.

NOTE. Anatolian Iron Age samples, from the Hellenistic period, which was obviously greatly influenced by different, later Indo-European migrations, does show a change in PCA.

Regarding CHG ancestry:

Ancient DNA findings suggest extensive population contact between the Caucasus and the steppe during the Copper Age (-5000-3000 BCE) (1, 2, 42). Particularly, the first identified presence of Caucasian genomic ancestry in steppe populations is through the Khvalynsk burials (2, 47) and that of steppe ancestry in the Caucasus is through Armenian Copper Age individuals (42). These admixture processes likely gave rise to the ancestry that later became typical of the Yamnaya pastoralists (7), whose IE language may have evolved under the influence of a Caucasian language, possibly ‘from the Maykop culture (50, 55). This scenario is consistent with both the “Copper Age steppe” (4) and the “Caucasian” models for the origin of the Proto-Anatolian language (56).

The CHG specific ancestry and the absence of EHG-related ancestry in Bronze Age Anatolia would be in accordance with intense cultural interactions between populations in the Caucasus and Anatolia observed during the late 5th millennium BCE that seem to come to an end in the first half of the 4th millennium BCE with the village-based egalitarian Kura-Araxes society (59, 60), thus preceding the emergence and dispersal of Proto-Anatolian.

Our results indicate that the early spread of IE languages into Anatolia was not associated with any large-scale steppe-related migration, as previously suggested (61). Additionally, and in agreement with the later historical record of the region (62), we find no correlation between genetic ancestry and exclusive ethnic or political identities among the populations of Bronze Age Central Anatolia, as has previously been hypothesized ( 63).

The Anatolian question

There is no steppe ancestry or R1b-M269 lineages near early historic Hittites. Yet.

Nevertheless, we already know about potentially similar cases:

So there seems to be thus no theoretical problem in accepting:

  • That neither steppe ancestry nor R1b-M269 subclades, already diminished in Bulgaria in the mid-5th millennium, did reach Anatolia, but only those Common Anatolian-speaking Aegean groups over whose ancestors Proto-Anatolians (marked by incoming EHG ancestry) would have previously dominated in the Balkans.
  • That steppe ancestry and R1b-M269 subclades did in fact arrive in the Aegean, but EHG was further diluted among the CHG-related population by the time of the historic Anatolian-speaking peoples in central Anatolia. Or, the most likely option, that their trace have not been yet found. Probably the western Luwian peoples, near Troy, were genetically closer to Common Anatolians.

Both of these scenarios are interesting, in that they show potential links between Pre-Greek peoples of Hellas (related to Anatolians) and the Pelasgian substrate of early Greek dialects, since they show a similar recent CHG-related wave from the East.

What we can assert right now is that Proto-Anatolian must have separated quite early for this kind of data to show up. This should mean an end to the Late PIE origin of Anatolian, if there was some lost soul from the mid-20th century still rooting for this.

As I said in my review of Lazaridis’ latest preprint, we will have to wait for the appropriate potential routes of expansion of Proto-Anatolian to be investigated. As he answered, the lack of EHG poses a problem for steppe expansion into Anatolia, but there is still no better alternative model proposed.

Eurasian-CHG-ancestry
Model-based clustering analysis of present-day and ancient individuals assuming K = 6 ancestral components. The main ancestry components at K = 6 correlate well with CHG (turquoise), a major component of Iran_N, Namazga_CA and South Asian dines; EHG (pale blue), a component of the steppe dine and present in South Asia; East Asia (yellow ochre), the other component of the steppe d ine also in Tibeto-Burman South Asian populations; South Indian (pink), a core component of South Asian populations; Anatolian_N (purple), an important component of Anatolian Bronze Age and Steppe_MLBA; Onge (dark pink) forms its own component.

This is what the authors have to say:

Our findings are thus consistent with historical models of cultural hybridity and “Middle Ground” in a multi-cultural and multi-lingual but genetically homogeneous Bronze Age Anatolia (68, 69). Current linguistic estimations converge on dating the Proto-Anatolian split from residual PIE to the late 5th or early 4th millennia BCE (58, 70) and place the breakup of Anatolian IE inside Turkey prior to the mid-3rd millennium (53, 71,72).

We cannot at this point reject a scenario in which the introduction of the Anatolian IE languages into Anatolia was coupled with the CHG-derived admixture prior to 3700 BCE, but note that this is contrary to the standard view that PIE arose in the steppe north of the Caucasus (4) and that CHG ancestry is also associated with several non-IE-speaking groups, historical and current. Indeed, our data are also consistent with the first speakers of Anatolian IE coming to the region by way of commercial contacts and small-scale movement during the Bronze Age. Among comparative linguists, a Balkan route for the introduction of Anatolian IE is generally considered more likely than a passage through the Caucasus, due, for example, to greater Anatolian IE presence and language diversity in the west (73). Further discussion of these options is given in the archaeological and linguistic supplementary discussions (48, 49).

If you are asking yourselves why the Danish school (of Allentoft, Kristiansen, and Kroonen, co-authors of this paper) was not so fast to explain the findings the same way the proposed their infamous Indo-European – steppe ancestry association (i.e. ancestry = language, ergo CHG = PIE in this case), and resorted to mainstream anthropological models instead to explain the incongruence, I can think of two main reasons:

The possibility of having an early PIE around the Caucasus, potentially closely related not only to Uralic to the north, but also to Caucasian languages, Sumerian, Afroasiatic, Elamo-Dravidian, etc. could be a good reason for those excited with these few samples to begin dealing with macro-language proposals, such as Eurasiatic and Nostratic. If demonstrated to be true, a Northern Iranian origin of Middle PIE would also help relieve a little bit the pressure that some are feeling about the potentially male-driven Indo-European continuity (even if not “autochthonous”) associated with the expansion of R1b-L23 subclades.

On the other hand, I am a firm supporter of solid anthropological models of migration, and of “late and small” language expansions, usually accompanied by demic diffusion, which has been demonstrated to be linked with haplogroup expansion and reduction in variability.

Therefore, for the moment, even if it is weak – as weak as it always was (but still stronger than Gimbutas’ Maykop route) – the Balkan route seems like the best fit for all the data combined.

In fact, we already have steppe ancestry moving into the Lower Danube and Bulgaria in the mid-5th millennium. Let’s not forget that.

Yamna expansion to the East

Interesting data from an early East Yamna offshoot at Karagash, ca. 3018-2887 BC, of R1b-Z2106 lineage, which shows some ancestry, lineage, and cultural continuity in Sholpan, ca. 2620-2468 BC, in Kazakhstan.

This sample might be part of another descendant group from the migration waves that reached Afanasevo, and can thus be related to other early Asian R1b-L23 samples found in Narasimhan et al. (2018).

On the formation of Yamna and its CHG contribution, from the supplementary material:

  1. An admixture event, where Yamnaya is formed from a CHG population related to KK1 [=Kotias, dated ca. 7800 BC] and an ANE population related to Sidelkino and Botai. We inferred 54% of the Yamnaya ancestry to come from CHG and the remaining 46% to come from ANE.
  2. A split event, where the CHG component of Yamnaya splits from KK1. The model inferred this time at 27 kya (though we note the larger models in Sections S2.12.4 and S2.12.5 inferred a more recent split time [see below graphic]).
  3. A split event, where the ANE component of Yamnaya splits from Sidelkino. This was inferred at about about 11 kya.
  4. A split event, where the ANE component of Yamnaya splits from Botai. We inferred this to occur 17 kya. Note that this is above the Sidelkino split time, so our model infers Yamnaya to be more closely related to the EHG Sidelkino, as expected.
  5. An ancestral split event between the CHG and ANE ancestral populations. This was inferred to occur around 40 kya.
yamnaya-chg-ancestry
A 10-leaf model based on combining the models in Fig. S16 and Fig. S19 and re-estimating the model parameters.

On the expansion of domestication

CHG is not found in Botai, no gene flow from Yamna is found in its samples, and they are more related to East Asians, while Yamna is related to West Eurasians:

The lack of evidence of admixture between Botai horse herders and western steppe pastoralists is consistent with these latter migrating through the central steppe but not settling until they reached the Altai to the east (4). More significantly, this lack of admixture suggests that horses were domesticated by hunter-gatherers not previously familiar with farming, as were the cases for dogs (38) and reindeer (39). Domestication of the horse thus may best parallel that of the reindeer, a food animal that can be milked and ridden, which has been proposed to be domesticated by hunters via the “prey path” (40); indeed anthropologists note similarities in cosmological beliefs between hunters and reindeer herders (41). In contrast, most animal domestications were achieved by settled agriculturalists (5).

NOTE. I am not sure, but they seem to hint that there were separate events of horse domestication and horse-riding technique by the Botai and Yamna populations due to their lack of genetic contribution from the latter to the former. I guess they did not take into account farming spreading to the steppe without genetic contribution beyond the Dnieper… In fact, the superiority in horse-riding shown by the expanding Yamna peoples – as they state – should also serve to suggest from where the original technique expanded.

Indo-Iranian migrations

On the expansion of Yamna, and the different expansion of Steppe MLBA (with Indo-Iranian speakers) into Asia, further supporting Narasimhan et al. (2018), they have this to say:

However, direct influence of Yamnaya or related cultures of that period is not visible in the archaeological record, except perhaps for a single burial mound in Sarazm in present-day Tajikistan of contested age (44, 45). Additionally, linguistic reconstruction of proto-culture coupled with the archaeological chronology evidences a Late (-2300-1200 BCE) rather than Early Bronze Age (-3000-2500 BCE) arrival of the Indo-Iranian languages into South Asia (16, 45, 46). Thus, debate persists as to how and when Western Eurasian genetic signatures and IE languages reached South Asia.

Samples from the Namazga region (current Turkmenistan) from the Iron Age show an obvious influence from steppe MLBA (ca. 2300-1200 BC), and not steppe EBA (i.e. Yamna), population, in contrast with samples from the Chalcolithic (ca. 3300 BC), which don’t show this influence. This helps distinguish prior contacts with Iran Neolithic from the actual steppe population that expanded Indo-Iranian into Asia.

Very interesting therefore the Namazga CA sample (ca. 855 BC), of R1a-Z93 subclade, showing the sign of immigrant Indo-Aryans in the region. For more on this we will need an evaluation in common with the corrected data from Narasimhan et al. (2018), and all, including de Barros (Nature 2018), in combination with statistical methods to ascertain differences between early Indo-Aryans and Iranians.

namazga-expansion-south-asia
A summary of the four qpAdm models fitted for South Asian populations. For each modern South Asian population. we fit different models with qpAdm to explain their ancestry composition using ancient groups and present the f irst model that we could not reject in the following priority order: 1. Namazga_CA + Onge, 2. Namazga_CA + Onge + Late Bronze Age Steppe, 3. Namazga_CA + Onge + Xiongnu_lA (East Asian proxy). and 4. Turkmenistan_lA + Xiongnu_lA. Xiongnu_lA were used here to represent East Asian ancestry. We observe that while South Asian Dravidian speakers can be modeled as a mixture of Onge and Namazga_CA. an additional source related to Late Bronze Age steppe groups is required for IE speakers. In Tibeto-Burman and Austro-Asiatic speakers. an East Asian rather than a Steppe_MLBA source is required.

Siberian peoples and N1c lineages

We have already seen how the paper on Eurasian steppe samples tries to assign Uralic to Neolithic peoples east of the Urals. The association with Okunevo is unlikely, since most are of haplogroup Q1a2, but they seem to suggest (combining both papers) that they accompanied N lineages from Siberian hunter-gatherers (present e.g. in Botai or Shamanka II, during the Early Neolithic), and formed part of (or suffered from) different demic diffusion waves:

These serial changes in the Baikal populations are reflected in Y-chromosome lineages (Fig. SA; figs. S24 to S27, and tables S13 and SI4). MAI carries the R haplogroup, whereas the majority of Baikal_EN males belong to N lineages, which were widely distributed across Northern Eurasia (29), and the Baikal_LNBA males all carry Q haplogroups, as do most of the Okunevo_EMBA as well as some present-day Central Asians and Siberians.

NOTE. Also interesting to see no R1a in Baikal hunter-gatherers after ca. 3500 BC, and a prevalence of N lineages as supported in a previous paper on the Kitoi culture, which some had questioned in the past.

In fact, the only N1c1 sample comes from Ust’Ida Late Neolithic, 180km to the north of Lake Baikal, apparently before the expansion of Q1a2a lineages during the EBA period. While this sample may be related to those expanded later in Finno-Ugric territory (although it may only be related to those expanded much later with Yakuts), other samples are not clearly from those found widely distributed among North-East Europeans only after the Iron Age, or – as in the case of Shamanka II (N1c2), they are clearly not of the same haplogroup.

eurasian-n-subclades
Geographical location of ancient samples belonging to major clade N of the Y-chromosome.

Wrap-up

It is great to see the paper and the supplementary material deal with Y-DNA haplogroups and their relevance for migrations with such detail. Especially because this paper comes from the same Copenhagen-based research group that originally associated ancestry with language, creating thus today’s mess based on steppe ancestry.

Regarding Y-DNA data, once again almost 100% of samples from late Khvalynsk/Yamna and derived cultures (like Afanasevo and Bell Beaker) are R1b-L23, no single R1a-M417 lineage found, and few expected by now, if any, within Late Proto-Indo-European territory.

While they claim to take Y-DNA into account to assess migrations – as they do for example with Asian cultures – , their previous model of a Yamna “R1a-R1b community” remains oddly unchanged, and they even insist on it in the supplementary materials, as they do in their parallel Nature paper.

They have also expressly mitigated the use of ancestral components to assess populations, citing the ancestral and modern association of CHG ancestry with different ethnolinguistic groups in the Middle East, to dismiss any rushed conclusions on the origin of Anatolian, and consequently of Middle PIE. And they did so evidently because it did not fit the anthropological data that is mainstream today (supporting a Balkan route), which is the right thing to do.

However, they have apparently not stopped to reconsider the links of CWC and steppe ancestry to ancestral and modern Uralic peoples – although they expressly mention the strong connection with modern Karelians in the supplementary material.

Also, after Narasimhan et al. (2018), there is a clear genetic continuity with East Yamna (in ancestry as in R1b-L23 subclades), so their interpretations about Indo-Iranian in this paper and especially de Barros (Nature 2018) – regarding the Abashevo -> Sintashta/Srunba/Andronovo connection – come, again, too late.

Related:

Lazaridis’ evolutionary history of human populations in Europe

Preprint of a review by Iosif Lazaridis, The evolutionary history of human populations in Europe.

Interesting excerpts:

Steppe populations during the Eneolithic to Bronze Age were a mix of at least two elements[28], the EHG who lived in eastern Europe ~8kya and a southern population element related to present-day Armenians[28], and ancient Caucasus hunter-gatherers[22], and farmers from Iran[24]. Steppe migrants made a massive impact in Central and Northern Europe post- 5kya[28,43]. Some of them expanded eastward, founding the Afanasievo culture[43] and also eventually reached India[24]. These expansions are probable vectors for the spread of Late Proto-Indo-European[44] languages from eastern Europe into both mainland Europe and parts of Asia, but the lack of steppe ancestry in the few known samples from Bronze Age Anatolia[45] raises the possibility that the steppe was not the ultimate origin of Proto-Indo-European (PIE), the common ancestral language of Anatolian speakers, Tocharians, and Late Proto-Indo Europeans. In the next few years this lingering mystery will be solved: either Anatolian speakers will be shown to possess steppe-related ancestry absent in earlier Anatolians (largely proving the steppe PIE hypothesis), or they will not (largely falsifying it, and pointing to a Near Eastern PIE homeland).

Our understanding of the spread of steppe ancestry into mainland Europe is becoming increasingly crisp. Samples from the Bell Beaker complex[46] are heterogeneous, with those from Iberia lacking steppe ancestry that was omnipresent in those from Central Europe, casting new light on the “pots vs. people” debate in archaeology, which argues that it is dangerous to propose a tight link between material culture and genetic origins. Nonetheless, it is also dangerous to dismiss it completely. Recent studies have shown that people associated with the Corded Ware culture in the Baltics[23,33] were genetically similar to those from Central Europe and to steppe pastoralists[28,43], and the people associated with the Bell Beaker culture in Britain traced ~90% of their ancestry to the continent, being highly similar to Bell Beaker populations there. Bell Beaker-associated individuals were bearers of steppe ancestry into the British Isles that was also present in Bronze Age Ireland[47], and Iron Age and Anglo-Saxon England[48]. The high genetic similarity between people from the British Isles and those of the continent makes it more difficult to trace migrations into the Isles. This high similarity masks a very detailed fine-scale population structure that has been revealed by study of present-day individuals[49]; a similar type of analysis applied to ancient DNA has the potential to reveal fine-grained population structure in ancient European populations as well.

Steppe ancestry did arrive into Iberia during the Bronze Age[50], but to a much lesser degree. A limited effect of steppe ancestry in Iberia is also shown by the study of mtDNA[51], which shows no detectible change during the Chalcolithic/Early Bronze Age[51], in contrast to central Europe[52]. Sex-biased gene flow has been implicated in the spread of steppe ancestry into Europe[33,53], although the presence and extent of such bias has been debated[54,55]. One aspect of the demographies of males and females was clearly different, as paternally-inherited Y-chromosome lineages experienced a bottleneck <10 kya which is not evident in maternally-inherited mtDNA[56], suggesting that many men living today trace their patrilineal ancestry to a relatively small number of men of the Neolithic and Bronze Ages.

lazaridis-europe
Modified image, from the preprint. “A sketch of European evolutionary history based on ancient DNA. Bronze Age Europeans (~4.5-3kya) were a mixture of mainly two proximate sources of ancestry: (i) the Neolithic farmers of ~8-5kya who were themselves variable mixtures of farmers from Anatolia and hunter-gatherers of mainland Europe (WHG), and (ii) Bronze Age steppe migrants of ~5kya who were themselves a mixture of hunter-gatherers of eastern Europe (EHG) and southern populations from the Near East (…)”

Firstly, Tocharian (mentioned side by side with Anatolian and LPIE) has been discussed by linguists for quite some time now to be a more archaizing language than the rest, hence the linguistic proposal that it separated first – found to correspond beautifully with the expansion of Khvalynsk/Repin into Afanasevo – ; but it separated first from the common Late PIE trunk. Anatolian clearly separated earlier, from a Middle PIE stage.

Secondly, while Genomics could no doubt falsify the Balkan route for Anatolian, and make us come back to a Maykop route from the steppe (or even a Near Eastern PIE homeland, who knows), I doubt such falsification could come simply from sampled “Anatolian speakers”:

If there is no steppe ancestry in Anatolian speakers (of the 2nd millennium BC), a dismissal of the mainstream migration model could happen only when both potential routes of expansion, the selected cultures from the Balkans and the Caucasus, are sampled in the appropriate time period since the estimated separation (i.e. from the 5th millennium BC), until one of both routes shows the right migration picture.

On the other hand, if some samples from either Romania/Bulgaria or the Caucasus (and/or Anatolian speakers) show steppe ancestry and/or R1b-M269 lineages, as is expected, then the matter won’t need much more explanation.

In fact, the text goes on to define how male lineages experienced a bottleneck after ca. 8000 BC, i.e. accompanying Neolithisation – probably including the formation of Sredni Stog and early Khvalynsk, as it is becoming now clear – , when explaining how it is possible to demonstrate that East Bell Beaker migrants (of R1b-L23 lineages, it is to be understood) with few steppe ancestry reached Iberia.

This was already pointed out not long ago by David Reich, and I am glad to see more scholars showing the importance of taking phylogeography into account over statistical methods when assessing migrations, even if it is only used in those cases in which it does not disrupt too much previous interpretations, like that of the 2015 papers and the proposal of the ‘Yamnaya ancestral component’.

I found it refreshing that for the first time Corded Ware migrants – or, rather, their shared genetic relationship with Eneolithic steppe groups – were accepted (if only indirectly) as a confounding factor in assessing migrations of Bell Beakers. It is a step in the right direction, and it is a relief to read this from someone working with the Reich Lab.

Not just a few (and not only amateurs) are still scratching their heads trying to explain with the most imaginative (and unnecessary) novel migration routes the elevated steppe ancestry and closer relation (PCA cluster, FST, F3, etc.) to CWC and Yamna (due evidently to the absorbed CWC population) in some of the recently published Bell Beaker samples from Central Europe, the Netherlands, and later in Great Britain, compared to samples of South-East Europe near the Middle to Upper Danube region, the obvious homeland of East Bell Beakers, formed from Yamna settlers.

I found it also interesting that Lazaridis mentioned a southern population element related to CHG and Iran farmers. This should help dissipate the hype that some have artificially created as of late over a potential Northern Iranian homeland based on a single paragraph from David Reich’s book.

EDIT (9 MAY 2018). Lazaridis posted an answer to my questioning of potential Proto-Anatolian origins divided in tweets (I post a link to the first tweet, then the text in full):

The steppe hypothesis predicts some genetic input from eastern Europe (EHG) to Anatolia.

– Bronze Age Anatolians (Lazaridis et al. 2017) from historically IE-speaking Pisidia lack EHG; more samples obviously needed

Possibilities:

  1. Additional Anatolian samples will have EHG: consistent with steppe PIE
  2. Additional Anatolian samples will not have EHG, then either:
    1. Steppe not PIE homeland
    2. Steppe PIE homeland but linguistic impact in Anatolia vastly greater than genetic impact

Tentative steppe->Anatolia movements reach Balkans early (Mathieson et al. 2018) and Armenia (some EHG in Lazaridis et al. 2016).

But not the last leg to Anatolia_ChL (Lazaridis et al. 2016) or Anatolia_BA (Lazaridis et al. 2017).

  • If Anatolians consistently don’t have EHG, steppe PIE is very difficult to affirm; Near Eastern alternative likely (contributing CHG/Iran_N-related ancestry to both western Anatolia/steppe)
  • If Anatolians have EHG, one could further investigate by what route they got it.

One way or another PIE homeland problem is almost solved IMHO, which is what my review tries to get at in that short section

Related:

Early Indo-Iranian formed mainly by R1b-Z2103 and R1a-Z93, Corded Ware out of Late PIE-speaking migrations

yamna-expansion-reich

The awaited, open access paper on Asian migrations is out: The Genomic Formation of South and Central Asia, by Narasimhan et al. bioRxiv (2018).

Abstract:

The genetic formation of Central and South Asian populations has been unclear because of an absence of ancient DNA. To address this gap, we generated genome-wide data from 362 ancient individuals, including the first from eastern Iran, Turan (Uzbekistan, Turkmenistan, and Tajikistan), Bronze Age Kazakhstan, and South Asia. Our data reveal a complex set of genetic sources that ultimately combined to form the ancestry of South Asians today. We document a southward spread of genetic ancestry from the Eurasian Steppe, correlating with the archaeologically known expansion of pastoralist sites from the Steppe to Turan in the Middle Bronze Age (2300-1500 BCE). These Steppe communities mixed genetically with peoples of the Bactria Margiana Archaeological Complex (BMAC) whom they encountered in Turan (primarily descendants of earlier agriculturalists of Iran), but there is no evidence that the main BMAC population contributed genetically to later South Asians. Instead, Steppe communities integrated farther south throughout the 2nd millennium BCE, and we show that they mixed with a more southern population that we document at multiple sites as outlier individuals exhibiting a distinctive mixture of ancestry related to Iranian agriculturalists and South Asian hunter-gathers. We call this group Indus Periphery because they were found at sites in cultural contact with the Indus Valley Civilization (IVC) and along its northern fringe, and also because they were genetically similar to post-IVC groups in the Swat Valley of Pakistan. By co-analyzing ancient DNA and genomic data from diverse present-day South Asians, we show that Indus Periphery-related people are the single most important source of ancestry in South Asia — consistent with the idea that the Indus Periphery individuals are providing us with the first direct look at the ancestry of peoples of the IVC — and we develop a model for the formation of present-day South Asians in terms of the temporally and geographically proximate sources of Indus Periphery-related, Steppe, and local South Asian hunter-gatherer-related ancestry. Our results show how ancestry from the Steppe genetically linked Europe and South Asia in the Bronze Age, and identifies the populations that almost certainly were responsible for spreading Indo-European languages across much of Eurasia.

NOTE. The supplementary material seems to be full of errors right now, because it lists as R1b-M269 (and further subclades) samples that have been previously expressly said were xM269, so we will have to wait to see if there are big surprises here. So, for example, samples from Mal’ta (M269), Iron Gates (M269 and L51), and Latvia Mesolithic (L51), a Deriivka sample from 5230 BC (M269), Armenia_EBA (Z2103)…Also, the sample from Yuzhnyy Oleni Ostrov is R1a-M417 now.

EDIT (1 APR 2018): The main author has confirmed on Twitter that they have used a new Y Chr caller that calls haplogroups given the data provided, and depending on the coverage tried to provide a call to the lowest branch of the tree possible, so there are obviously a lot of mistakes – not just in the subclades of R. A revision of the paper is on its way, and soon more people will be able to work with the actual samples, since they say they are releasing them.

Nevertheless, since it is subclades (and not haplogroups) the apparent source of gross errors, for the moment it seems we can say with a great degree of confidence that:

  • New samples of East Yamna / Poltavka are of haplogroup R1b-L23.
  • Afanasevo is confirmed to be dominated by R1b-M269.
  • Sintashta, as I predicted could happen, shows a mixed R1b-L23/ R1a-Z645 society, compatible with my model of continuity of Proto-Indo-Iranian in the East Yamna admixture with late Corded Ware immigrants.

With lesser confidence in precise subclades, we find that:

  • A sample from Hajji Firuz in Iran ca. 5650 BC, of subclade R1b-Z2103, may confirm Mesolithic R1b-M269 lineages from the Caucasus as the source of CHG ancestry to Khvalynsk/Yamna, and be thus the reason why Reich wrote about a potential PIE homeland south of the Caucasus . (EDIT 11 APR 2018) The sample shows steppe ancestry, therefore the date is most likely incorrect, and a new radiocarbon dating is due. It is still interesting – depending on the precise subclade – for its potential relationship with IE migrations into the area.
  • New samples of East Yamna / Poltavka are of haplogroup R1b-Z2103.
  • Afanasevo migrants are mainly of haplogroup R1b-Z2103.
    • The Darra-e Kur sample, ca. 2655, of haplogroup R1b-L151, without a clear cultural adscription, may be the expected sign of Afanasevo migrants (Pre-Proto-Tocharian speakers) expanding a Northern Indo-European (in contrast with a Southern or Graeco-Aryan) dialect, in a region closely linked with the later desert mummies in the Tarim Basin. Its early presence there would speak in favour of a migration through the Inner Asian Mountain Corridor previous to the one caused by Andronovo migrants.
  • Sintashta shows a mixed R1b-Z2103 / R1a-Z93 society.
    • Later Indo-Iranian migrations are apparently dominated by R1a-Z2123, an early subclade of R1a-Z93, also found in Srubna.
    • R1b is also seen later in BMAC (ca. 1487 BC), although its subclade is not given.
  • There is also a sample of R1a-Z283 subclade in the eastern steppe (ca. 1600 BC). What may be interesting about it is that it could mark one of the subclades not responsible for the expansion of Balto-Slavic (or responsible for it with the expansion of Srubna, for those who support an Indo-Slavonic branch related Sintashta-Potapovka).
  • A sample of R1b-U106 subclade is found in Loebanr_IA ca. 950 BC, which – together with the sample of Darra-e Kur – is compatible with the presence of L51 in Yamna.

NOTE. Errors in haplogroups of previously published samples make every subclade of new samples from the supplementary table questionable, but all new samples (safe for the Darra_i_Kur one) were analysed and probably reported by the Reich Lab, and at least upper subclades in each haplogroup tree seem mostly coherent with what was expected. Also, the contribution of Iranian Farmer related (a population in turn contributing to Hajji Firuz) to Khvalynsk in their sketch of the genetic history may be a sign of the association of R1b-M269 lineages with CHG ancestry, although previous data on precise R1b subclades in the region contradict this. (EDIT 11 APR 2018) The sample of Hajji Firuz is most likely much younger than the published date, hence its younger subclade may be correct. No revision or comment on this matter has been published, though.

yamna-steppe-emba-mlba-cloud
Modeling results. (A) Admixture events originating from 7 “Distal” populations leading 538 to the formation of the modern Indian cloud shown geographically. Clines or 2-way mixtures of 539 ancestry are shown in rectangles, and clouds (3-way mixtures) are shown in ellipses.

Also, it seems that the Corded Ware culture appears now irrelevant for Late Proto-Indo-European migrations. Observe:

In the text, a consistent terminology of Yamnaya or Yamnaya-related Steppe pastoralists, discarding the relevance of previous migrations from the North Pontic steppe in spreading Late Indo-European:

Our results also shed light on the question of the origins of the subset of Indo-European languages spoken in India and Europe (45). It is striking that the great majority of Indo-European speakers today living in both Europe and South Asia harbor large fractions of ancestry related to Yamnaya Steppe pastoralists (corresponding genetically to the Steppe_EMBA cluster), suggesting that “Late Proto-Indo-European”—the language ancestral to all modern Indo- European languages—was the language of the Yamnaya (46). While ancient DNA studies have documented westward movements of peoples from the Steppe that plausibly spread this ancestry to Europe (5, 31), there has not been ancient DNA evidence of the chain 488 of transmission to South Asia. Our documentation of a large-scale genetic pressure from Steppe_MLBA groups in the 2nd millennium BCE provides a prime candidate, a finding that is consistent with archaeological evidence of connections between material culture in the Kazakh middle-to-late Bronze Age Steppe and early Vedic culture in India (46).

EDIT (1 APR 2018): I corrected this text and the word ‘official’ in the title, because more than rejecting the role of Corded Ware migrants in expanding Late PIE, they actually seem to keep considering Corded Ware migrants as continuing the western Yamna expansion in the Carpathian Basin, so no big ‘official’ change or retraction in this paper, just subtle movements out of their previous model.

yamna-migrations-indo-iranian
Modeling results.(B) A 540 schematic model of events originating from 7 “Distal” populations leading to the formation of 541 the modern Indian cline, shown chronologically. (C) Admixture proportions as estimated 542 using qpAdm for populations reflected in A and B.

NOTE. If they correct the haplogroups soon, I will update the information in this post. Unless there is a big surprise that merits a new one, of course.

EDIT (1 APR 2018): Multiple minor edits to the original post.

EDIT (2 APR 2018): While I and other simple-minded people were only looking to confirm our previous theories using Y-DNA haplogroups, and are content with wildly speculating over the consequences if some of those strange (probably wrong) ones were true, intelligent people are using their time for something useful, interpreting the results of the investigation as described in the paper, to offer a clearer picture of Indo-Iranian migrations for everyone:

Visit the beautiful interactive map with samples: with their location, PCA, ADMIXTURE and haplogroups (still with those originally given): https://public.tableau.com/profile/vagheesh#!/vizhome/TheGenomicFormationofSouthandCentralAsia/Fig_1

Featured image, from the article: “A Tale of Two Subcontinents. The prehistory of South Asia and Europe are parallel in both being impacted by two successive spreads, the first from the Near East after 7000 BCE bringing agriculturalists who mixed with local hunter-gatherers, and the second from the Steppe after 3000 BCE bringing people who spoke Indo-European languages and who mixed with those they encountered during their migratory movement. Mixtures of these mixed populations then produced the rough clines of ancestry present in both South Asia and in Europe today (albeit with more variable proportions of local hunter-gatherer-related ancestry in Europe than in India), which are (imperfectly) correlated to geography. The plot shows in contour lines the time of the expansion of Near Eastern agriculture. Human movements and mixtures, which also plausibly contributed to the spread of languages, are shown with arrows.”

Related:

Proto-Indo-European homeland south of the Caucasus?

User Camulogène Rix at Anthrogenica posted an interesting excerpt of Reich’s new book in a thread on ancient DNA studies in the news (emphasis mine):

Ancient DNA available from this time in Anatolia shows no evidence of steppe ancestry similar to that in the Yamnaya (although the evidence here is circumstantial as no ancient DNA from the Hittites themselves has yet been published). This suggests to me that the most likely location of the population that first spoke an Indo-European language was south of the Caucasus Mountains, perhaps in present-day Iran or Armenia, because ancient DNA from people who lived there matches what we would expect for a source population both for the Yamnaya and for ancient Anatolians. If this scenario is right the population sent one branch up into the steppe-mixing with steppe hunter-gatherers in a one-to-one ratio to become the Yamnaya as described earlier- and another to Anatolia to found the ancestors of people there who spoke languages such as Hittite.

The thread has since logically become a trolling hell, and it seems not to be working right for hours now.

Reich’s proposal based on ancestral components to explain the formation of a people and language is a continuation of their emphasis on ancestry to explain cultures and languages. It seems quite interesting to see this happen again, given their current trend to surreptitiously modify their previous ‘Yamnaya ancestry’ concept and Yamnaya millennia-long R1a-R1b community (that supposedly explains a Yamna -> Corded Ware -> Bell Beaker migration) to a more general ‘steppe people’ sharing a ‘steppe ancestry’ who spoke a ‘steppe language’.

steppe-ancestry
Interesting arrows of dispersal of steppe ancestry, from Yamna -> Corded Ware -> Bell Beaker, from David Reich’s new book (yes, from 2018, number one bestseller in Amazon.com).

This new idea based on ancestral components suffers thus from the same essential methodological problems, which equate it – yet again – to pure speculation:

  1. It is a conclusion based on the genomic analysis of few individuals from distant regions and different periods, and – maybe more disturbingly – on the lack of steppe ancestry in the few samples at hand.
  2. Wait, what? Steppe ancestry? So they are trying to derive potential genetic connections among specific prehistoric cultures with a poorly depicted genetic sketch, based on previous flawed concepts (instead of on anthropological disciplines), which seems a rather long stretch for any scientist, whether they are content with seeing themselves as barbaric scientific conquerors of academic disciplines or not. In other words, statistics is also science (in fact, the main one to assert anything in almost any scientific field), and you cannot overcome essential errors (design, sampling, hypothesis testing) merely by using a priori correct statistical methods. Results obtained this way constitute a statistical fallacy.

  3. Even if the sampling and hypothesis testing were fine, to derive anthropological models from genomic investigation is completely wrong. Ancestral component ≠ population.
  4. To include not only potential migrations, but also languages spoken by these potential migrants? It’s sad that we have a need to repeat it, but if ancestral component ≠ population, how could ancestral component = language?

The Proto-Indo-European-speaking community

This is what we know about the formation of a Proto-Indo-European community (i.e. a community speaking a reconstructible Proto-Indo-European language) in the Pontic-Caspian steppe, which is based on linguistic reconstruction and guesstimates, tracing archaeological cultures backwards from cultures known to have spoken ancient (proto-)languages, and helping both disciplines with anthropological models (for which ancient genomics is only helping select certain details) of migration or – rarely – cultural diffusion:

NOTE. The following dates are obviously simplified. Read here a more detailed linguistic assessment based on phonology.

neolithic_steppe-anatolian-migrations
Most likely Pre-Proto-Anatolian migration with Suvorovo-Novodanilovka chiefs in the North Pontic steppe and the Balkans.
  • ca. 5000 BC. Early Proto-Indo-European (or Indo-Uralic) spoken probably during the formation and development of a loose Early Khvalynsk – Sredni Stog I cultural-historical community over the Pontic-Caspian steppe region, whose indigenous population probably had mainly Caucasus hunter-gatherer ancestry.
  • ca. 4500 BC. Khvalynsk probably speaking Middle Proto-Indo-European expands, most likely including Suvorovo-Novodanilovka chiefs into the North Pontic steppe, and probably expanding R1b-M269 lineages for the first time.
  • ca. 4000 BC. Separated communities develop, including North Pontic cultures probably gradually dominated by R1a-Z645 (potentially speaking Proto-Uralic); and Khvalynsk (and Repin) cultures probably dominated by R1b-L23 lineages, most likely developing a Late Proto-Indo-European already separated from Proto-Anatolian.
  • ca. 3500 BC. A Proto-Corded Ware population dominated by R1a-Z645 expands to the north, and slightly later an early Yamna community develops from Late Khvalynsk and Repin, expanding to the west of the Don River, and to the east into Afanasevo. This is most likely the period of reduction of variability and expansion of subclades of R1a-Z645 and R1b-L23 that we expect to see with more samples.
  • ca. 3000 BC. Expansion of Corded Ware migrants in northern Europe, and Yamna migrants along the Danube and into the Balkans, with further reduction and expansion of certain subclades.
  • ca. 2500 BC. Expansion of Bell Beaker migrants dominated by R1b-L51 subclades in Europe, and late Corded Ware migrants in east Yamna expanding R1a-Z93 subclades.

All these events are compatible with language reconstruction in mainstream European schools since at least the 1980s, supported by traditional archaeological research of the past 20 years, and is being confirmed with Genomics.

For those willingly lost in a myriad of new dreams boosted by the shallow comment contained in David Reich’s paragraph on CHG ancestry, even he does not doubt that the origin of Late Proto-Indo-European lies in Yamna, to the north of the Caucasus, based on Anthony’s (2007) account:

yamnaya-migrations-reich
Both images from the book, posted by Twitter user Jasper at https://twitter.com/jaspergregory.

NOTE: By the way, David Anthony, one of the main sources of information for Reich’s group, never considered Corded Ware to have received Yamna migrants, and althought he changed his model due to the conclusions of the 2015 papers, he has recently changed his model again to adapt it to the inconsistencies found in phylogeography.

CHG ancestry and PIE homeland south of the Caucasus

As for the potential origins of CHG ancestry in early Proto-Indo-European speakers, I already stated clearly my opinion quite recently. They may be attributed to:

Just to be clear, an expansion of Proto-Anatolian to the south, through the Caucasus, cannot be discarded today. It will remain a possibility until Maykop and more Balkan Chalcolithic and Anatolian-speaking samples are published.

However, an original Early Proto-Indo-European community south of the Caucasus seems to me highly unlikely, based on anthropological data, which should drive any conclusion. From what I could read, here are the rather simplistic arguments used:

  • Gimbutas and Maykop: Maykop was thought to be (in Gimbutas’ times) a rather late archaeological culture, directly connected to a Transcaucasian Copper Age culture ca. 2400-2300 BC. It has been demonstrated in recent years that this culture is substantially older, and even then language guesstimates for a Late PIE / Proto-Anatolian would not fit a migration to the north. While our ignorance may certainly be used to derive far-fetched conclusions about potential migrations from and to it, using Gimbutas (or any archaeological theory until the 1990s) today does not make any sense. Still less if we think that she favoured a steppe homeland.

NOTE. It seems that the Reich Lab may have already access to Maykop samples, so this suggested Proto-Indo-European – Maykop connection may have some real foundation. Regardless, we already know that intense contacts happened, so there will be no surprise (unless Y-DNA shows some sort of direct continuity from one to the other).

  • Gamkrelidze & Ivanov: they argued for an Armenian homeland (and are thus at the origin of yet another autochthonous continuity theory), but they did so to support their glottalic theory, i.e. merely to support what they saw as favouring their linguistic model (with Armenian being the most archaic dialect). The glottalic theory is supported today – as far as I know – mainly by Kortlandt, Jagodziński, or (Nostraticist) Bomhard, but even they most likely would not need to argue for an Armenian homeland. In fact, their support of a Graeco-Aryan group (also supported by Gamkrelidze & Ivanov) would be against this, at least in archaeological terms.
  • Colin Renfrew and the Anatolian homeland: This conceptual umbrella of language spreading with farming everywhere has changed so much and so many times in the past 20 years, with so many glottochronological and archaeological estimates circulating, that you can support anything by now using them. Mostly used today for abstract models of long-lasting language contacts, cultural diffusion, and constellation analogies. Anyway, he strives to keep up-to-date information to revise the model, that much is certain:
  • Glottochronology, phylogenetic trees, Swadesh list analysis, statistical estimates, psychics, pyramid power, and healing crystals: no, please, no.
Science Magazine
“A first line of evidence comes from linguistic analysis based on quantitative lexical data, which returned a tree compatible with the Anatolian hypothesis

In principle, unlike many other recent autochthonous continuity theories, I doubt there can be much racial-based opposition anywhere in the world to an origin of Proto-Indo-European in the Middle East, where the oldest civilizations appeared – apart, obviously, from modern Northeast and Northwest Caucasian, Kartvelian, or Semitic speakers, who may in turn have to revisit their autochthonous continuity theories radically…

Nevertheless, it is obvious that prehistoric (and many historic) migrations are signalled by the reduction in variability and expansion of certain Y-DNA haplogroups, and not just by ancestral components. That is generally accepted, although the reasons for this almost universal phenomenon are not always clear.

In fact, Proto-Anatolian and Common Anatolian speakers need not share any ancestral component, PCA cluster, or any other statistical parameter related to steppe populations, not even the same Y-DNA haplogroups, given that approximately three thousand years might have passed between their split from an Indo-Hittite community and the first attested Anatolian-speaking communities…We must carefully follow their tracks from Anatolia ca. 1500 BC to the steppe ca. 4500 BC, otherwise we risk creating another mess like the Corded Ware one.

In my opinion, the substantial contribution of EHG ancestry and R1a-M417 lineages to the Pontic-Caspian steppe (probably ca. 6500 BC) from Central or East Eurasia is the most recent sizeable genomic event in the region, and thus the best candidate for the community that expanded a language ancestral to Proto-Indo-European – whether you call it Pre-Proto-Indo-European, Pre-Indo-Uralic, or Eurasiatic, depending on your preferences.

An early (and substantial) contribution of CHG ancestry in Khvalynsk relative to North Pontic cultures, if it is found with new samples, may actually be a further proof of the Caucasian substrate of Proto-Indo-European proposed by Kortlandt (or Bomhard) as contributing to the differentiation of Middle PIE from Uralic. Genomics could thus help support, again, traditional disciplines in accepting or rejecting academic controversial theories.

Conclusion

In the case of an Early PIE (or Indo-Uralic) homeland, genomic data is scarce. But all traditional anthropological disciplines point to the Pontic-Caspian steppe, so we should stick to it, regardless of the informal suggestion written by a renown geneticist in one paragraph of a book conceived as an introduction to the field.

It seems we are not learning much from the hundreds of peer-reviewed, statistically (superficially, at least) sound genetic papers whose anthropological conclusions have been proven wrong by now. A lot of people should be spending their time learning about the complex, endless methods at hand in this kind of research – not just bioinformatics – , instead of fruitlessly speculating about wild unsubstantiated proposals.

As a final note, I would like to remind some in the discussion, who seem to dismiss the identification of CHG with Proto-Indo-European by supporting a “R1a-R1b” community for PIE, of their previous commitment to ancestral components in identifying peoples and languages, and thus their support to Reich’s (and his group’s) fundamental premises.

You cannot have it both ways. At least David Reich is being consistent.

Related:

The uneasy relationship between Archaeology and Ancient Genomics

Allentoft Corded Ware

News feature Divided by DNA: The uneasy relationship between archaeology and ancient genomics, Two fields in the midst of a technological revolution are struggling to reconcile their views of the past, by Ewen Callaway, Nature (2018) 555:573-576.

Interesting excerpts (emphasis mine):

In duelling 2015 Nature papers6,7the teams arrived at broadly similar conclusions: an influx of herders from the grassland steppes of present-day Russia and Ukraine — linked to Yamnaya cultural artefacts and practices such as pit burial mounds — had replaced much of the gene pool of central and Western Europe around 4,500–5,000 years ago. This was coincident with the disappearance of Neolithic pottery, burial styles and other cultural expressions and the emergence of Corded Ware cultural artefacts, which are distributed throughout northern and central Europe. “These results were a shock to the archaeological community,” Kristiansen says.

(…)

Still, not everyone was satisfied. In an essay8 titled ‘Kossinna’s Smile’, archaeologist Volker Heyd at the University of Bristol, UK, disagreed, not with the conclusion that people moved west from the steppe, but with how their genetic signatures were conflated with complex cultural expressions. Corded Ware and Yamnaya burials are more different than they are similar, and there is evidence of cultural exchange, at least, between the Russian steppe and regions west that predate Yamnaya culture, he says. None of these facts negates the conclusions of the genetics papers, but they underscore the insufficiency of the articles in addressing the questions that archaeologists are interested in, he argued. “While I have no doubt they are basically right, it is the complexity of the past that is not reflected,” Heyd wrote, before issuing a call to arms. “Instead of letting geneticists determine the agenda and set the message, we should teach them about complexity in past human actions.”

Many archaeologists are also trying to understand and engage with the inconvenient findings from genetics. (…)
[Carlin:] “I would characterize a lot of these papers as ‘map and describe’. They’re looking at the movement of genetic signatures, but in terms of how or why that’s happening, those things aren’t being explored,” says Carlin, who is no longer disturbed by the disconnect. “I am increasingly reconciling myself to the view that archaeology and ancient DNA are telling different stories.” The changes in cultural and social practices that he studies might coincide with the population shifts that Reich and his team are uncovering, but they don’t necessarily have to. And such biological insights will never fully explain the human experiences captured in the archaeological record.

Reich agrees that his field is in a “map-making phase”, and that genetics is only sketching out the rough contours of the past. Sweeping conclusions, such as those put forth in the 2015 steppe migration papers, will give way to regionally focused studies with more subtlety.

This is already starting to happen. Although the Bell Beaker study found a profound shift in the genetic make-up of Britain, it rejected the notion that the cultural phenomenon was associated with a single population. In Iberia, individuals buried with Bell Beaker goods were closely related to earlier local populations and shared little ancestry with Beaker-associated individuals from northern Europe (who were related to steppe groups such as the Yamnaya). The pots did the moving, not the people.

This final paragraph apparently sums up a view that Reich has of this field, since he repeats it:

Reich concedes that his field hasn’t always handled the past with the nuance or accuracy that archaeologists and historians would like. But he hopes they will eventually be swayed by the insights his field can bring. “We’re barbarians coming late to the study of the human past,” Reich says. “But it’s dangerous to ignore barbarians.”

I would say that the true barbarians didn’t have a habit or possibility to learn from the higher civilizations they attacked or invaded. Geneticists, on the other hand, only have to do what they expect archaeologists to do: study.

EDIT (30 MAR 2018): A new interesting editorial of Nature, On the use and abuse of ancient DNA.

See also:

Palaeogenomic and biostatistical analysis of ancient DNA data from Mesolithic and Neolithic skeletal remains

lepenski-vir-mesolithic-anatolia-neolithic

PhD Thesis Palaeogenomic and biostatistical analysis of ancient DNA data from Mesolithic and Neolithic skeletal remains, by Zuzana Hofmanova (2017) at the University of Mainz.
Abstract:

Palaeogenomic data have illuminated several important periods of human past with surprising im- plications for our understanding of human evolution. One of the major changes in human prehistory was Neolithisation, the introduction of the farming lifestyle to human societies. Farming originated in the Fertile Crescent approximately 10,000 years BC and in Europe it was associated with a major population turnover. Ancient DNA from Anatolia, the presumed source area of the demic spread to Europe, and the Balkans, one of the first known contact zones between local hunter-gatherers and incoming farmers, was obtained from roughly contemporaneous human remains dated to ∼6 th millennium BC. This new unprecedented dataset comprised of 86 full mitogenomes, five whole genomes (7.1–3.7x coverage) and 20 high coverage (7.6–93.8x) genomic samples. The Aegean Neolithic pop- ulation, relatively homogeneous on both sides of the Aegean Sea, was positively proven to be a core zone for demic spread of farmers to Europe. The farmers were shown to migrate through the central Balkans and while the local sedentary hunter-gathers of Vlasac in the Danube Gorges seemed to be isolated from the farmers coming from the south, the individuals of the Aegean origin infiltrated the nearby hunter-gatherer community of Lepenski Vir. The intensity of infiltration increased over time and even though there was an impact of the Danubian hunter-gatherers on genetic variation of Neolithic central Europe, the Aegean ancestry dominated during the introduction of farming to the continent.

Taking only admixture analyses using Yamna samples:

This increased genetic affinity of Neolithic farmers to Danubians was observed for Neolithic Hungarians, LBK from central Europe and LBK Stuttgart sample. Some post-Neolithic samples also proved to share more drift with Danubians, again samples from Hungary (Bronze Age and Copper Age samples and also Yamnaya and samples with elevated Yamnaya ancestry (Early Bronze Age samples from Únětice, Bell Beaker samples, Late Neolithic Karlsdorf sample and Corded Ware samples).

(…)

The results of our ADMIXTURE analysis for the dataset including also Yamnaya samples are shown in Figure S1c. The cross-validation error was the lowest for K=2. Supervised and unsupervised analyses for K=3 are again highly concordant. Early Neolithic farmers again demonstrate almost no evidence of hunter-gatherer admixture, while it is observable in the Middle Neolithic farmers. However, much of the Late Neolithic hunter-gatherer ancestry from the previous analysis is replaced by Yamnaya ancestry. These results are consistent with the results of Haak et al. who demonstrated a resurgence of hunter-gatherer ancestry followed by the establishment of Eastern hunter-gatherer ancestry.

Again, admixture results show that something in the simplistic Yamna -> Corded Ware model is off. It is still interesting to review admixture results of European Mesolithic and Late Neolithic genomic data in relation to the so-called steppe or yamna ancestry or component (most likely an eastern steppe / forest zone ancestry probably also present in the earlier Corded Ware horizons) and its interpretation…

yamna-ancestry-europe
Image composed by me, from two different images of the PhD Thesis. To the left: Supervised run of ADMIXTURE. The clusters to be supervised were chosen to best fit the presumed ancestral populations (for HG Motala and for farmers Bar8 and Bar31 and for later Eastern migration Yamnaya). To the Right: Unsupervised run of ADMIXTURE for the Anatolian genomic dataset with Yamnaya samples for K=8.

Discovered via Généalogie génétique