A reappraisal of the Indo-European migration from Iran starting from the new linguistic paper of Heggarty

Nine years ago I proposed a west Iranian homeland (in the Zagros mountains) for Indo-Europeans (see here). After that, there were genetic studies that discovered a Caucasus Hunter Gatherers component that spread to the steppe and a similar Iranian Neolithic component (in the Zagros) that spread to the east, and when it was discovered that this component was present in Bronze Age Anatolia without steppe ancestry, the South of Caucasus homeland has received new support. Now, also in linguistics, there is a trend in that direction, and a new, big stone has been thrown in the pool of Indo-European studies:

Paul Heggarty et al. , Language trees with sampled ancestors support a hybrid model for the origin of Indo-European languages.Science381,eabg0818(2023).DOI:10.1126/science.abg0818

It is a linguistic study based on lexical evolution, comparing the vocabulary of 161 Indo-European languages, and connecting the results with geography and genetics. The map above shows the general reconstruction: Proto-Indo-European started to split around 8100 years ago, south of Caucasus, in the region of origin of Caucasus Hunter Gatherers/Iran Neolithic ancestry. As they write: "This CHG/Iranian component is found first south of the Caucasus, including in the north to northeastern arc of the Fertile Crescent, among early farmers on the flanks of the Zagros Mountains in western Iran. The same CHG/Iranian ancestry component also admixes heavily (by ~5000 yr B.P.) into the region where languages of the Anatolian branch are first documented. CHG/Iranian is the dominant ancestry in ancient Armenia and Iran, in BMAC, and in most present-day populations who speak languages of the Iranic branch. It is also a major ancestry component among speakers of the Indic branch, particularly in regions furthest from the Dravidian-speaking (i.e., non–Indo-European) south of India. Thus, it is the CHG/Iranian ancestry component that most strongly connects the past populations who potentially spoke the branches of Indo-European in Europe and south (and east) of the Caucasus. [...] we propose a hybrid hypothesis in which Indo-European languages spread out of an initial homeland south of the Caucasus, in the northern Fertile Crescent. Only one major branch spread northward onto the steppe and then across much of Europe."

This major branch would be the NW Indo-European group, already known in Indo-European studies, including Italic, Celtic, Germanic, Balto-Slavic, but without Tocharian that is usually included in the group. Archaeologically and genetically, it seems that all this group is originally connected with the Corded Ware culture, from which derived also the central European Bell Beaker people. The separation of this big branch is here dated 6981 BP (5645‒8395), around the time of the arrival of CHG in the steppe according to ancient DNA studies.  

Albanian, Armenian and Greek instead are placed apart (and not with a SE group with Indo-Iranic as proposed by some), and separated around 6135 BP (4540‒7882). So, as shown in the map, they would have migrated through Anatolia to the Balkans without passing by the steppe. This is denied by the paper of Lazaridis, "The genetic history of the Southern Arc" that proposed instead that Greeks and Armenians came from Yamnaya expansions, bringing steppe ancestry to Greece and Armenia during the Bronze Age. This view is also consistent with the kind of R1b Y DNA lineages (L23) that is shared by ancient Greeks and Armenians in the 2nd millennium BCE, connected with Yamnaya.  

Moreover, the separation of Anatolian is dated 6932 BP (5403‒8613), which means that Greeks moved to Anatolia later than Anatolians, and it is not clear how this could happen and why they did not settle somewhere in Anatolia and did not push Anatolians towards Greece. One can observe that in Greece there are some famous Anatolian-like toponyms like Parnassos. But I have to cite here from a work of Tardivo and Kitselis: "the mountain name Παρνασσός has a Luwian equivalent Parnassa, which is believed to be derived from the Luwian root parna ‘house’, a word that lacks secure cognates outside Anatolia. Comparable material is found nearby in the Mediterranean region like the Egyptian pr “house” and Hurrian pur(u)li “house”."

Anyway, this can be explained as the substrate of Anatolian migrants with a CHG ancestry who arrived in Greece already at the beginning of the Bronze Age.

About Indo-Iranic, their separation is dated 6981 BP like the NW branch, as if they departed at the same time. The separation of Indic, instead, is dated 5520 BP (4535‒6796), as if they reached South Asia much later, as is suggested by the map indeed. I appreciate very much that they accept a route directly through Iran rather than through the steppes, but I find the movement towards India too slow.

Now, although dates of known historical language changes correspond quite well to the dates of this study based on lexical comparison, I have many doubts on the validity of these prehistoric dates, but let us see if there is some correspondence with what we know from archaeology.

The initial division of Indo-Europeans is so described: "Our hybrid hypothesis posits that out of this homeland south of the Caucasus, from ~8120 yr B.P., PIE began to diverge as early migrations split it into multiple early branches." Now, 8120 BP means 6170 BCE. It is an interesting period, because it is associated with a dramatic climatic change, the so-called 8.2-kiloyear event. This event, apparently starting from the Atlantic, "like the Younger Dryas and 9.2ka BP event, was marked by abrupt cooling and aridity across much of the world" (Matthews and Nashli 2022). According to an article by Flohr et al. of 2015 ("Evidence of resilience to past climate change in Southwest Asia: Early farming communities and the 9.2 and 8.2 ka events"), "The so-called 8.2 ka event was one of the most pronounced and abrupt Holocene cold and arid events. [...] Sharp decreases in air temperature of up to 4°C are also evident in many other high-resolution proxy records from the circum-Atlantic and Mediterranean basin. [...] It appears that wetness increased north of 42° latitude, while aridity increased south of this. For the Eastern Mediterranean, a reduction in precipitation of around 17% has been calculated. The event is well-dated to have taken place between 8250 and 8000 cal BP and to have lasted around 160 years." About the consequences, Matthews and Nashli write: "it has been suggested that the Neolithic movement into the Zagros foothills and Fars may have been stimulated by this century-long episode. [...] across the plains of central and northern Iran there is as yet no convincing sign of local precursors to the well-adapted Neolithic farmers and herders who spread into the region from c. 6000 BC, bringing their domesticated herds and grains with them. Where did they come from? The likeliest hypothesis for the time-being is that they moved into central and northern Iran from the west, steadily advancing across the Zagros ranges and foothills from areas where farming had already been practiced for up to 2000 years. Why did they move? To what extent their movement was stimulated by climatic adversity attendant upon the 8.2 ka BP event remains unclear, but there appears to be an at least approximate contemporaneity. [...] As to the dispersal of Neolithic lifeways eastwards from Iran into Turkmenistan and beyond, the many material culture connections between the Neolithic sites of north-eastern Iran and those of southern Turkmenistan across the Kopet Dagh, such as Monjukli Depe, are highly suggestive. The first point to make is that, yet again, the appearance of the earliest Jeitun culture sites in Turkmenistan appears to coincide with the 8.2 ka BP event (Harris 2010: 233; see also Düring 2011: 124–125 for possible impact of the 8.2 ka BP event on agricultural expansion across Turkey). The presence of domesticated sheep by 6000 BC at Obishir V in southern Kyrgyzstan suggests a relatively rapid spread of Neolithic herding practices eastwards from southern Turkmenistan across challenging terrain. Secondly, there is no evidence for local development of the Neolithic in Turkmenistan or beyond. David Harris summarises the Neolithic of southern Turkmenistan thus: 

The general uniformity of the material culture of the Jeitun-Culture settlements, especially their mudbrick architecture and chaff-tempered pottery, supports the inference that they were initially founded as sedentary settlements by migrants seeking new land to occupy with their crops and livestock. (Harris 2010: 233) 

Finally, Harris concludes that the dispersal of Neolithic settlers, with their herds and plants, towards Turkmenistan took place across the northern reaches of Iran, an “inviting corridor” leading from the Zagros to the Kopet Dagh."

So, possibly before 6000 BCE the sudden cold and aridity pushed people down from the north-central Zagros towards the Caspian region and beyond, to Turkmenistan, areas where we later find the cradle of the Iranic world. A Neolithic presence in the Caspian region was already around 7000 BCE in Sang-e Chakhmaq West, but it was much more limited, and did not reach Central Asia. Interestingly, also in Baluchistan we have a new kind of Neolithic dated from 6000 BCE by Jarrige (although Ceccarelli and Petrie give a date of c.5470-4700 BCE from the deposits of Period IIA), in Mehrgarh Period II: "Pottery appeared in Period II; it is vegetal-tempered, comparable to the Neolithic pottery found in Iran including at the site of Tepe Yahya and in the Daulatabad Plain. Some Period II vessels display applied decorations, a feature observable on vegetal-tempered vessels from Tal-i Iblis. Jean-François Jarrige, however, has compared these decorations more specifically with those from Umm Dabaghiyah in northern Iraq. Additionally, the technique used to create this pottery, namely sequential slab construction, has also been identified on Neolithic vessels from Iran as well as at Umm Dabaghiyah." (Mutin and Garazhian 2021) Jarrige (2008: 150) made also another comparison with Umm Dabaghiyah about Period II: "The impressive plans of compartmented buildings of Period IIA can be compared with buildings with similar plans from Mesopotamian sites such as Tell el Oueili or Umm Dabaghiyah at the end of the 7th millennium BC. It is probably not a mere chance if one notices the occurrence at Umm Dabaghiyah and at Mehrgarh, Period IIA, of some potsherds not only built according to the same sequential slab construction but also bearing similar applied designs." 

Now, a connection of Umm Dabaghiyah in North Mesopotamia with Mehrgarh in Baluchistan seems quite unlikely at first sight. But there are also connections with an important site southwest of the Urmia lake, Hajji Firuz Tepe in Iranian Azerbaijan, as Matthews and Nashli report: "Concerning the origin of the first settlers at Hajji Firuz, on the basis of the pottery Voigt (1983: 166) argues for connections across the northern Zagros to the west into Upper Mesopotamia, with sites such as Telul eth-Thalathat, Sotto and Umm Dabaghiyah." Voigt (see here, p.166) spoke of a single tradition of manufacture and decoration of ceramics in Hajji Firuz and early Hassuna, which means Umm Dabaghiyah. She proposed that the area (Ushnu-Solduz valley south of Lake Urmia) was settled by cultivators and herders coming from the west, where they were in contact with early Hassuna groups or with their ancestors, and found a continuity of contacts in the later period. She also wrote (p.168) of a chain of sites from Hassuna-Samarra in central Mesopotamia to Tepe Sarab in Mahidasht, to Tepe Sialk in the central Iranian plateau. To extend the chain up to Mehrgarh, we can add what Fagan (1996: 437) has written: "At Mehrgarh, continuity and change is marked with the introduction of soft ware, Buff Ware or Chaff Tempered Pottery in period Mehrgarh IIA. This ceramic seems to have broad similarities on the Iranian plateau (e.g., Yahya period vii-v, Tepe Sialk, Belt & Hotu Caves) perhaps far west in the Zagros (Jarmo)".  We can also add a direct parallel by Vandiver (1987: 18) between the ceramic of Hajji Firuz and Mehrgarh: "At Hajji Firuz about twenty sherds with negative basket impressions in the base have delaminated from an outer surface layer which has a positive but less distinct basket impression. At Mehrgarh, J.-F. Jarrige has reported about five similar sherds, in addition to some with basket straw still embedded in the wall." And Ceccarelli-Petrie (2020: 4): "what is referred to as Burj Basket-Marked ware was among the earliest ceramics identified in the archaeological record of South Asia. For this technique, potters used baskets as a mould, and vessels were often coated with a clay slip to hide basket impressions. This combination of techniques also seems to have been quite widespread from the Near East to South Asia, as suggested by evidence from Abu Hureyra (Syria), Ali Kosh and Hajji Firuz Tepe (Iran)." About Ali Kosh at the southwestern border of Central Zagros (dated from 7500 to 6500 BCE), Jarrige (2008: 151-152) noticed other affinities already from Period I, that he dates from before 7000 BCE (while Petrie from 6000 BCE): "the full setting of farming economy at Mehrgarh displays evident similarities with what had been noticed in the case of the early Neolithic settlements in the hilly regions forming the eastern border of Mesopotamia. The circular houses of the earliest Neolithic villages have not been found at Mehrgarh. But quadrangular houses built with about 60 cm long narrow bricks with a herringbone pattern of impressions of thumbs to provide a keying for the mud-mortar, have been uncovered at several aceramic Neolithic sites in the Zagros, such as Ganj Dareh or Ali Kosh in the Deh Luran region of Iran, where, like at Mehrgarh, traces of red paint have also been noticed on the walls. Circular fire-pits filled with burnt pebbles are also associated to all these early settlements. The lithic industries also show evident parallels [...] polished-stone axes begin occurring at several sites of the Deh Luran area, such as Ali Kosh, only in the later phases of the aceramic Neolithic along with an increasing number of stone vessels. It is the same at Mehrgarh where the polished stone axes in black diorite are found only in the upper levels of Period I, mostly as gravegoods. [...] the few graves exposed at Ali Kosh show skeletons with positions rather similar to those of Mehrgarh. Among the gravegoods one notices ornaments made of seashells and semi-precious stones such as turquoise, a few beads in copper. Baskets coated with bitumen and oblong-shaped cakes of red-ochre strengthen the parallels."

 

The subsequent innovations appearing both in sites between Mesopotamia and central Zagros and in Mehrgarh suggest a repeated contact between these distant regions, as if it followed an established route. In Sotto, a site near Umm Dabaghiyah, there is also the earliest finding of lapis lazuli in Mesopotamia, which would confirm exchanges with Central Asia (see here). But then, do we have just a chain of cultural exchanges from Mesopotamia to Baluchistan, or also a movement of people? And did this movement start from Mesopotamia? In a passage about the site of Yanik Tepe (northeast of Lake Urmia) Matthews and Nashli write: "Objects include many alabaster bowl and bracelet fragments, comparable to those from Neolithic sites of the Zagros, and bone and obsidian tools using obsidian from south Caucasian and north Iranian sources. A small stone figurine takes the form of a human head with clear representation of artificial cranial elongation (Figure 5.45), also a key trait of the Zagros Neolithic. Chaff-tempered pottery, occasionally painted, compares well to Neolithic ceramics from Hajji Firuz to the southwest of Lake Urmia. The alabaster bracelets and evidence for cranial elongation suggest a Zagros origin for the Neolithic settlers of the Lake Urmia basin rather than a development from local hunter–gatherer communities, until now conspicuous by their absence from the archaeological record." 

So, did people of Lake Urmia in Late Neolithic come from the central Zagros or from Mesopotamia?

Ajorloo (2008: 114) observes that there are two Pottery Neolithic sites, Ahrendjān and Qara Tepe to the northwest of Lake Urmia, earlier than Hajji Firuz: "According to the field data it is possible to prove that the Hajji Firuz is not the first stage in the formation process of the early villages in Azerbaijan. Therefore it seems the hypothesis of the migrant people of the Hassuna sphere to the west bank of the Urmia Lake can not explain the Neolithization process in the region." And in a later paper (Ajorloo 2016: 157): "while Ahrendjān-Qara Tepe wares stand in a range attested to the Proto-Hassuna horizon, c. 6700-6200 BC, the radiocarbon dates put Hājji Firūz not earlier than c. 6000 BC, and, moreover, there are some remarkable resemblances between the Ahrendjān-Qara Tepe ceramic assemblage and Sarāb, Gūrān II, Abdul Hosein II and even Jarmo II which fall within a range of c. 7000-6500 BC. Such a chronology is also roughly in accordance with the retreat of Lake Urmia and the emergence of a transhumance way of life in the Central Zagros. Consequently, in general terms, it is reasonable to propose a relative dating for Ahrendjān-Qara Tepe as c. 6500-6000 BC." But if the Urmia basin was settled by transhumant herders from the central Zagros, this does not exclude that also people from Mesopotamia arrived, probably agriculturists, especially in Hajji Firuz, where the connections with Hassuna culture are particularly strong: "In addition to incised decoration, like the Hassuna pottery, the pottery tradition of Hājji Firūz includes husking trays, pithoi and wide-mouth wares; such types being related to agricultural activities. On the contrary, in the Ahrendjān-Qara Tepe tradition they had been using forms appropriate to dairy products like spouted vessels, collared jars and narrow mouth vessels. The husking tray is recognized as one of the indicators for the Late Neolithic period in northern Mesopotamia and the Hassunan/Samarran horizon but as yet no husking tray has been recorded from the Ahrendjān-Qara Tepe tradition and the well-known Neolithic sites in the Zagros, for example Jarmo II, Gūrān II, Abdul Hosein II, Sarāb and Ganj Dareh A-D" (Ajorloo 2016: 153).

Today luckily we have a genetic study of Hajji Firuz around 6000 BCE or slightly later, that has revealed that the ancestry of the people was double: 53% Anatolia Neolithic, 47% Ganj Dareh Neolithic (Narasimhan 2019, supplement, p.196). So, the answer to our question seems to be that the people of Hajji Firuz came from both directions. Not only, we also have the Y DNA haplogroups: two of them are J2b, a haplogroup that was found also in Tepe Abdul Hosein around 8000 BCE, in central Zagros Neolithic, with a pure Iran Neolithic autosomal ancestry. This means that J2b was part of Iran Neolithic people of central Zagros, and interestingly it is quite frequent in Albanians, Greeks, and South Asians. J2b2 was found also in three Mycenaean samples (Mygdalia) and in several Balkanic samples of the Bronze Age, probably belonging to proto-Illyrians (see here). 

About the autosomal ancestry, the study of Broushaki on the three samples from Abdul Hosein and one from Wezmeh Cave (a later site in central Zagros) found out that "Zoroastrians are the most genetically similar to all four Neolithic Iranians, followed by other modern Iranians (Fars), Balochi (SE-Iran, Pakistan and Afghanistan), Brahui (Pakistan and Afghanistan), Kalash (Pakistan) and Georgians". Most of these peoples are Indo-Iranian speakers, Dravidian Brahuis are genetically very similar to Baluchis, and Georgians are geographically close and have special connections with Indo-European.

Moreover, according to Ajorloo (2016: 153), among all central Zagros sites, Abdul Hosein II shows more similarities in term of shapes and forms of the ceramics with Ahrendjān and Qara Tepe near Lake Urmia: we can suppose that some people from this village went to the north in search of pastures and their descendants settled also in Hajji Firuz. 

On the maternal side, one of the two men with J2b from Hajji Firuz Tepe had mtDNA K1a3, and K1a has been found not only in Barcın in Northwestern Anatolia Neolithic, but also in two Pre-Pottery Neolithic sites in Mesopotamia, Boncuklu Tarla near Mardin and Çayönü (where also specifically K1a3 is present), and also in Proto-Neolithic Shanidar, on the Iraqi side of the Zagros. These Mesopotamian and Zagros sites have a significant amount of Central Zagros Neolithic ancestry, and Çayönü has also revealed a female outlier with more of that ancestry and also with artificial cranial deformation, a feature (caused by head bandage) well known in central Zagros (Ganj Dareh, Abdul Hosein), in Shanidar Cave, Ali Kosh, and also, as we have seen, in the figurines of Yanik Tepe in the Urmia region. The Çayönü male with K1a3 mtDNA has J2a1a as Y DNA, which connects him with Caucasus Hunter Gatherers and Iran Mesolithic: J2a has been found in Kotias Klde in Georgia (8th mill. BCE), in Hotu Cave south of Caspian Sea (dated 9100-8600 BCE) and in Neolithic Tepe Guran in central Zagros (6700 BCE). Moreover, J2a1a, besides later Anatolian samples (including Phrygian Gordion), was also in Armenia Neolithic (Aknashen and Masis Blur), in Mycenaean Greece, in Tepe Hissar (3640-3518 calBCE), in Geoksyur in Turkmenistan (3365-3097 calBCE), in Shahr-i Sokhta (2600-2500 BCE), and in the Urmia region in the Late Bronze/Iron age (Dinkha and Hasanlu Tepe). And J2a1h was the important Indus_Periphery_West individual from Shahr-i Sokhta (and another Indus Periphery sample there is J2a), but also a local individual from the same site, one of Tepe Hissar (3641-3519 calBCE), and some later individuals from Swat and Central Asia. J2a1h is also especially frequent among Zoroastrians in Iran (15.4% in Tehran and 17.6% in Yazd, and also 17% of Persians from Yazd, as shown by Grugni 2012, where it is called J2a3h, while J2a3*-Page55=J2a1* is even 23% in Zoroastrians from Tehran).

Thus, J2a1 has a good connection with Indo-Iranians, Greeks, Phrygians and Anatolians, very conservative Indo-European branches for many morphological and phonetical aspects, and not sharing the special vocabulary characteristic of the NW Indo-European branch. And clearly this haplogroup starts from south of the Caucasus. 

The Indus_Periphery_West individual from Shahr-i Sokhta, dated 3100-3000 BCE, is important because it was analyzed in the paper of Shinde et al. (2019: 4): "To obtain insight into the origin of the Iranian-related ancestry in the IVC Cline, we co-modeled the highest-coverage individual from the IVC Cline, Indus_Periphery_West (who also happens to have one of the highest proportions of Iranian-related ancestry) with other ancient individuals from across the Iranian plateau representing early hunter-gatherer and food-producing groups: a ⁓10,000 BCE individual from Belt Cave in the Alborsz Mountains, a pool of ⁓8000 BCE early goat herders from Ganj Dareh in the Zagros Mountains, a pool of ⁓6000 BCE farmers from Hajji Firuz in the Zagros Mountains, and a pool of ⁓4000 BCE farmers from Tepe Hissar in Central Iran. [...] The only consistently fitting models specified that the Iranian-related lineage contributing to the IVC Cline split from the Iranian-related lineages sampled from ancient genomes of the Iranian plateau before the latter separated from each other [...] The Belt Cave individual dates to ⁓10,000 BCE, definitively before the advent of farming anywhere in Iran, which implies that the split leading to the Iranian-related component in the IVC Cline predates the advent of farming there as well. Even if we do not consider the results from the low-coverage Belt Cave individual, our analysis shows that the Iranian-related lineage present in the IVC Cline individuals split before the date of the ⁓8000 BCE Ganj Dareh individuals, who lived in the Zagros mountains of the Iranian plateau before crop farming began there around ⁓7000–6000 BCE. Thus, the Iranian-related ancestry in the IVC Cline descends from a different group of hunter-gatherers from the ancestors of the earliest known farmers or herders in the western Iranian plateau." 

What they say here about Ganj Dareh is not correct, because the Neolithic people of all levels (8200-7600 BCE) there used domesticated cereals: "Regarding plant exploitation, the people of Ganj Dareh utilised domesticated two-row hulled barley (Hordeum distichum) in increasing amounts through levels E to A" (Matthews and Nashli 2022: 69). But also the analysis and the conclusions were contested by another paper, by Maier et al. (2023: 50): "The combined Indus Periphery group we analyzed included seven individuals from Shahr-i-Sokhta and three individuals from Gonur (three individuals were removed from the Narasimhan et al., 2019 dataset due to potential contamination with modern human DNA and low coverage). We removed one individual from the Ganj Dareh Neolithic group as potentially contaminated, and one second- or third-degree relative was removed from the Anatolia Neolithic group [...] A model ‘Indus Periphery = Ganj Dareh Neolithic + Onge (ASI)’ was strongly rejected for the Indus Periphery group of 10 individuals [...] and a model that was shown to be fitting for all Indus Periphery individuals modeled one by one by Narasimhan et al. (Ganj Dareh Neolithic + Onge (ASI) + West Siberian hunter–gatherers (WSHG)) was rejected for the grouped individuals [...] In contrast, a model ‘Indus Periphery = Ganj Dareh Neolithic + Onge (ASI) + WSHG + Anatolia Neolithic’ was not rejected [...] and produced plausible admixture proportions for all four sources that are confidently above zero: 53.2 ± 5.3%, 28.7 ± 2.1%, 10.5 ± 1.3%, and 7.7 ± 2.9%, respectively" 

This means that an Anatolia Neolithic component, clearly present in Hajji Firuz, Tepe Hissar and other post-6000 BCE Iranian sites, should be recognized also in Indus Periphery individuals, and so a migration from western Iran is not rejected. They also add (p.51): "we show four graphs with four admixture events that model the Indus Periphery group as a mixture of three or four sources, with a significant fraction of its ancestry derived from the Hajji Firuz Neolithic or Tepe Hissar Chalcolithic lineages including both Iranian and Anatolian ancestries. [...] a key historical conclusion of the study (that the predominant genetic component in the Indus Periphery lineage diverged from the Iranian clade prior to the date of the Ganj Dareh Neolithic group at ca. 10 kya and thus prior to the arrival of West Asian crops and Anatolian genetics in Iran) depends on the parsimony assumption, but the preference for three admixture events instead of four is hard to justify based on archaeological or other arguments. [...] the inconsistency reflects the fact that the deeply diverging WSHG-related ancestry (Narasimhan et  al., 2019) present in the IVC (Indus Valley Civilization genetic grouping, which is the same group as Indus Periphery) at a level of ca. 10% was not taken into account explicitly" 

See here for the 4 graphs. Here are two examples:

As we see, it is possible that Indus Periphery received admixture from an ancestry close to Tepe Hissar, or from an ancestry related to Hajji Firuz and another Iranian source parallel to Ganj Dareh. Many possibilities are there, but considering Y DNA, the fact that J2a1h is found also earlier in Tepe Hissar can be a hint of a connection. It can be also significant that according to the skeletal studies of Hemphill, Lukacs and Kennedy, Harappans had the closest affinities with Tepe Hissar period III. 

An interesting detail about the Indus Periphery West individual is that in his burial "Salvatori et al. note that a distinctive pottery type among the grave goods belongs to a distinctive cluster of graves at Shahr-i-Sokhta that is “possibly local or northeast oriented (Kandahar area)”" (Narasimhan 2019, supplement, p.115). Maybe this individual was from the region of Kandahar, where there was Mundigak, a site that was possibly founded by people coming from Baluchistan according to Jarrige (1993: 26):

"Work conducted at Mehrgarh has clearly shown that the cultural assemblage of the preurban phases of Mundigak (period IV) is closely linked to Baluchistan. The foundation of Mundigak can even be interpreted as the settling of people from Baluchistan who were probably aware of the importance of such a location for the control of the nearby mineral resources. The remains from period I at Mundigak fit almost perfectly the cultural assemblage of period III at Mehrgarh, dated to the end of the fifth and the very beginning of the fourth millennium b.c." 

 

That region, Greek Arachosia, had the Avestan Harahvaiti river, a name that corresponds to Sanskrit Sarasvati and has no other parallels in Iranic. We can suppose that people from Mundigak were Indo-Aryan speakers with an Indus Periphery genetic profile. About Mehrgarh III, the Chalcolithic phase, it has many developments compared with the Neolithic phase, but it is considered in continuity for architecture, ceramic technology, subsistence, although Hemphill, Lukacs and Kennedy noticed a great difference in the people of this phase compared to Period I, with close affinity with Iranian Tepe Hissar and Near Eastern skeletons, while Period I has affinity with later Inamgaon in Maharashtra, which suggests a type closer to South Indians. They placed the change thus between 6000 and 4500 BCE, but there is no analysis of Period II. In aceramic Period I there were already some elements from Iran/Mesopotamia, including kinds of wheat a probably also domesticated barley, although wild barley was also present. But we have seen that pottery and architecture of Period II had special connections with western cultural phenomena. Maybe, the initial aceramic Neolithic was mainly due to cultural contact, with local evolutions like zebu domestication, but in the course of time Iranian immigrants became dominant, especially after the 8.2 ka event. They colonized Baluchistan, bringing proto-Indo-Iranian language, during the 6th millennium BCE, progressively spreading to the east into South Asia, but also going to the west in Arachosia around 4000 BCE. Narasimhan et al. (2019: 11) suggest that the migration to South Asia is not later than 6000 BCE: "although our analysis supports the idea that eastward spread of Anatolian farmer–related ancestry was associated with the spread of farming to the Iranian plateau and Turan, our results do not support large-scale eastward movements of ancestry from western Asia into South Asia after ~6000 BCE (the time after which all ancient individuals from Iran in our data have substantial Anatolian farmer–related ancestry, in contrast to South Asians who have very little)" 

On the other hand, they place the admixture with Andamanese-like ancestry creating the Indus Periphery cline "by ~5400 to 3700 BCE", which is in the range of Period II-III of Mehrgarh in the chronology of Petrie. According to Heggarty, the separation of Indic from Indo-Iranic can be placed in 5520 BP (4535‒6796), that is, around 3570 BCE, with a large range starting from 4846 BCE. We can place the real development of Indo-Aryan after the assimilation of South Asian non-Indo-European people, with special features like retroflexion. The developments of Iranic can be due instead to the "Anatolian" influence, that possibly caused the loss of aspiration and spirantization.

But was there a memory in Iranic tradition of this migration? Avestan Vendidad 2 says (in the translation of Darmesteter):

5. And the fair Yima replied unto me, O Zarathushtra, saying: 'Yes! I will make thy world increase, I will make thy world grow. Yes! I will nourish, and rule, and watch over thy world. There shall be, while I am king, neither cold wind not hot wind, neither disease nor death.' 6. Then I, Ahura Mazda, brought two implements unto him: a golden seal and a poniard inlaid with gold. Behold, here Yima bears the royal sway! 8. Thus, under the sway of Yima, three hundred winters passed away, and the earth was replenished with flocks and herds, with men and dogs and birds and with red blazing fires, and there was room no more for flocks, herds, and men. 9. Then I warned the fair Yima, saying: 'O fair Yima, son of Vivanghat, the earth has become full of flocks and herds, of men and dogs and birds and of red blazing fires, and there is room no more for flocks, herds, and men.' 10. Then Yima stepped forward, in light, southwards, on the way of the sun, and (afterwards) he pressed the earth with the golden seal, and bored it with the poniard, speaking thus: 'O Spenta Armaiti, kindly open asunder and stretch thyself afar, to bear flocks and herds and men.' 11. And Yima made the earth grow larger by one-third than it was before, and there came flocks and herds and men, at their will and wish, as many as he wished. 12. Thus, under the sway of Yima, six hundred winters passed away, and the earth was replenished with flocks and herds, with men and dogs and birds and with red blazing fires, and there was room no more for flocks, herds, and men. 13. And I warned the fair Yima, saying: 'O fair Yima, son of Vivanghat, the earth has become full of flocks and herds, of men and dogs and birds and of red blazing fires, and there is room no more for flocks, herds, and men.' 14. Then Yima stepped forward, in light, southwards, on the way of the sun, and (afterwards) he pressed the earth with the golden seal, and bored it with the poniard, speaking thus: 'O Spenta Armaiti, kindly) open asunder and stretch thyself afar, to bear flocks and herds and men.' 15. And Yima made the earth grow larger by two-thirds than it was before, and there came flocks and herds and men, at their will and wish, as many as he wished. 16. Thus, under the sway of Yima, nine hundred winters passed away10, and the earth was replenished with flocks and herds, with men and dogs and birds and with red blazing fires, and there was room no more for flocks, herds, and men. 20. The Maker, Ahura Mazda, called together a meeting of the celestial Yazatas in the Airyana Vaejo of high renown, by the Vanguhi Daitya. The fair Yima, the good shepherd, called together a meeting of the best of the mortals, in the Airyana Vaejo of high renown, by the Vanguhi Daitya. 21. To that meeting came Ahura Mazda, in the Airyana Vaejo of high renown, by the Vanguhi Daitya; he came together with the celestial Yazatas. To that meeting came the fair Yima, the good shepherd, in the Airyana Vaejo of high renown, by the Vanguhi Daitya; he came together with the best of the mortals. 22. And Ahura Mazda spake unto Yima, saying: 'O fair Yima, son of Vivanghat! Upon the material world the evil winters are about to fall, that shall bring the fierce, deadly frost; upon the material world the evil winters are about to fall, that shall make snow-flakes fall thick, even an aredvi deep on the highest tops of mountains. 23. And the beasts that live in the wilderness, and those that live on the tops of the mountains, and those that live in the bosom of the dale shall take shelter in underground abodes." And then, he had to create the Vara, a sort of underground garden where the best humans and animals and plants were preserved from the winter. Is this a memory of a special cold period like the 8.2 ka event? And where was really Airyanam Vaejo? Maybe we should reevaluate the identification of Bundahishn, that placed it "bordering Azerbaijan", and Darmesteter's identification of the river Daitya with the Araxes. Maybe we should think of the region around the Urmia lake, that has been a refuge also during the Bronze Age, when great part of Iranian sites were abandoned. And maybe we should include the central Zagros, the cradle of Iranian Neolithic, with its caves like Shanidar and Wezmeh. If there was a movement in the late Neolithic from there to the East Iranian and Central Asian Avestan homeland, did they completely forget their origin?  Giacomo Benedetti, Impruneta, 17/8/2023

  

 

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