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Saturday, 31 March 2018

Harvard's ''Genomic Formation of South and Central Asia ''

So here we have an aDNA paper from Narasimhan et al , published at bioRxiv today. It is a big paper, containing more than 350 ancient samples, from important ancient sites of Central Asia ,Iran and also S Asia. The apparent impression from the first read is that, they have found ''evidence'' of migration from Steppe to S Asia. They don't have Mature Harappan samples, which is a shame.The S Asian samples are from Swat/Pakistan dating from only around 1200 bce to historical period. In those samples they have found no R1a except a singleton R1a from Saidu_Sharif_IA I6891 (500-300 BCE) .The archaeological  studies from the past have shown that Swat culture had largely female centered characteristics rather than the expected opposite , see here for example.The importance of feminine  is also reflected in modern culture of Kalash also, like freedom of women, and goddess cult, see here.
Interestingly, they have ruled out BMAC as potential source population of S Asians, this goes against the traditional AIT model . I am suspecting for example, the West Siberian HG ancestry they have discovered is actually Central Asian HG component ,which included N India.In the BMAC main cluster they measure this ancestry at 13%, but in Sarazm EN , it had around 25% presence(just as in the samples from Pakistan!, suggesting dilution by West Asian migration rather than what they imply.) , in their qpAdm based analysis(p.22 main paper) we only see the green Siberian HG ancestry appearing in ancient S Asians, while EHG related one is absent. From main paper p.9:
Third, between 3100-2200 BCE we observe an outlier at the BMAC site of Gonur, as well as two outliers from the eastern Iranian site of Shahr-i-Sokhta, all with an ancestry profile similar to 41 ancient individuals from northern Pakistan who lived approximately a millennium later in the isolated Swat region of the northern Indus Valley (1200-800 BCE). These individuals had between 14-42% of their ancestry related to the AASI and the rest related to early Iranian agriculturalists and West_Siberian_HG.
There cannot be any doubt that this West_Siberian_HG-related ancestry was in  N India since at least 3000 BCE, but probably much earlier. Also finding ancestry related to ''S Asian HG''s may imply, that it was  also well present in N India prior to 2000 bce , but was it uniformly present? only aDNA from India will clarify.Their argument is mainly based on the samples like  Gonur2_BA migrant being representative of the whole SSVC population!. But in near future, if we get samples from SSVC proper and they show  strong relation to the SPGT samples, the whole argument falls.They also didn't find the S Asia specific R1a-L657, in any of their ancient samples ...

The Genomic Formation of South and Central Asia
            Vagheesh  M Narasimhan et al.
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.


Friday, 9 March 2018

Intensified summer monsoon and the urbanization of Indus Civilization in northwest India

Yama Dixit, David A. Hodell, Alena Giesche, Sampat K. Tandon, Fernando Gázquez, Hari S. Saini, Luke C. Skinner, Syed A. I. Mujtaba, Vikas Pawar, Ravindra N. Singh & Cameron A. Petrie
Today the desert margins of northwest India are dry and unable to support large populations, but were densely occupied by the populations of the Indus Civilization during the middle to late Holocene. The hydroclimatic conditions under which Indus urbanization took place, which was marked by a period of expanded settlement into the Thar Desert margins, remains poorly understood. We measured the isotopic values (δ18O and δD) of gypsum hydration water in paleolake Karsandi sediments in northern Rajasthan to infer past changes in lake hydrology, which is sensitive to changing amounts of precipitation and evaporation. Our record reveals that relatively wet conditions prevailed at the northern edge of Rajasthan from ~5.1 ± 0.2 ka BP, during the beginning of the agricultural-based Early Harappan phase of the Indus Civilization. Monsoon rainfall intensified further between 5.0 and 4.4 ka BP, during the period when Indus urban centres developed in the western Thar Desert margin and on the plains of Haryana to its north. Drier conditions set in sometime after 4.4 ka BP, and by ~3.9 ka BP an eastward shift of populations had occurred. Our findings provide evidence that climate change was associated with both the expansion and contraction of Indus urbanism along the desert margin in northwest India.
 Location of (A) Urban Harappan sites at ∼4.6–4.5 ka BP and (B) Post- Urban Harappan after ~4.1–4.0 ka BP sites in NW India as denoted by the orange dots in each case. Note that the urban-Harappan sites are located on the margin of the Thar Desert and the post-urban Harappan sites are clustered to the right of paleolake Karsandi on the Indo-Gangetic plains. The location of Karsandi shown by the white triangle and other reported paleolakes in black triangles.

It is increasingly evident that the landscapes across which Indus populations lived were diverse in terms of climate, geology and ecology, and the patterns of cultural behavior and response to climate variability are unlikely to have been uniform throughout the Indus region16,24. The paleoclimate record from paleolake Karsandi clearly suggests there were areas receiving favorable rainfall in the period leading up to the development of Indus urban centres along the northern fringe of the Thar Desert in NW India. This evidence underscores the importance of reconstructing local conditions for understanding the degree of adaptation and resilience of ancient civilization exhibited to climate change.
Yog .

See also :
Adaptation to Variable Environments, Resilience to Climate Change: Investigating Land, Water and Settlement in Indus Northwest India
Oxygen isotope in archaeological bioapatites from India: Implications to climate change and decline of Bronze Age Harappan civilization
Holocene landscape dynamics in the Ghaggar-Hakra palaeochannel region at the northern edge of the Thar Desert, northwest India
The Chronology of Puranic Kings and Rigvedic Rishis in Comparison with the Phases of the Sindhu–Sarasvati Civilization
Painted Grey Ware Culture: Changing Perspectives

Wednesday, 7 March 2018

Painted Grey Ware Culture: Changing Perspectives

With important updates . 

Painted Grey Ware Culture: Changing Perspectives
Vinay Kumar Gupta1 and B.R.Mani 2
Abstract:Painted Grey Ware culture is  one of the significant archeological cultures of northern India.It  has been a subject of attraction and debate among scholars. The most crucial aspect about this culture has been its chronology and its proposed relation to the  Mahabharata.The issue of its authorship is equally important.This article discusses all these issues afresh in the light of the new radiocarbon dates obtained from various sites and the first author’s detailed archaeological survey in the Mathura region, a core area  of Painted Grey Ware culture. This article voices for a change  in  the  accepted  chronology of this culture   and   takes   back   its antiquity by  many centuries. A proposition is also made about the place of origin of this culture which differs from the earlier propositions.
Keywords: PGW,OCP, BSW,NBPW,Grey Ware,Mahabharata,Radiocarbon Date


See also :
Implications of a Recent Hoard of Copper Objects from Harinagar,District Bijnor,Uttar Pradesh

Thursday, 1 March 2018

Comparison chart of the elements from various ancient cultures correlating with Vedic elements

As we wait for the important aDNA papers of India . Lets take a look at this beautiful comparison chart thanks to a friend .