The most prominent among the archaeological sites in the Kachi-Bolan plain in Balochistan is Mehrgadh. The settlement was located on one of the major communication corridors between the Iranian Plateau, Central Asia and the Indus Valley; what is now the National Highway 65 (Pakistan) connecting Quetta in Balochistan to Kandahar in Afghanistan. Around 7,000 BCE, Mehrgadh was a small farming and pastoralist village with mud brick houses and granaries. The residents used local copper ore, baskets lined with bitumen, and an array of bone tools – all made by using the material found locally. Crops harvested during this period included barley (six-rowed) and wheat (einkorn and emmer), both wild and domesticated; they also ate wild Indian jujube (boram), and dates. Sheep, goats, and cattle were herded for milk and meat. Hunted animals included gazelle, swamp deer, nilgai, wild ass, chital, water buffalo, wild pig, and elephant [Hirst, 2017: Mehrgadh, Pakistan – Life in the Indus Valley Before Harappa]. The conditions in Mehrgadh at that point of time were probably favourable for its development as a farming and pastoralist settlement. The climatic conditions were definitely better than now; the results of the pollen analysis published by Costantini et al in 1997 show that, from about 7,000 BCE to about 4,000 BCE the region was probably a fertile plain formed of shallow lake beds with humid climate. Mehrgadh lies on the margins of foothills in an alluvial plain; the mountains to its north-west rise 2,000 meters above mean sea level and the alluvial plain is less than 100 meters above mean sea level. Thus it has a wide range of ecosystems within a limited mobility, providing variety of resources. Wild ancestors of the animals and plants which, later on were to be predominant among the domesticated species – goats, sheep, cattle, barley and wheat – were native to this heterogeneous environment [Jarrige, 2006: Mehrgadh Neolithic, in Pragdhara, No 18, 139].
Who were these farmers and herders of Mehrgadh? Could they be natives of the Kachi-Bolan plain? According to Joseph, “whoever left behind the evidence of their settlement in Mehrgadh starting from around 7000 BCE couldn’t have been thriving there for longer than a few thousand years before that.” That is because, it must have been a cold arid desert, till about 11,500 BCE or 10,500 BCE; Joseph puts it at 9,700 BCE [Joseph, 2018: Early Indians: The Story of Our Ancestors and Where We Came From, 52]. These farmers-herders must have migrated to the Kachi-Bolan plain only a “few thousand years” before 7,000 BCE, possibly drawn by its potential for farming and herding.
We do not know for sure from where the settlers came to Mehrgadh; and why. One reason could be, as said above, its potential for farming and herding. Just before 7,000 BCE, the melting of ice had reached its maximum and temperatures had more or less stabilised. This could have made the Kachi-Bolan Plain and the Greater Indus Valley beyond it, a ‘greener pasture’ worth exploring. The fact that they remained settled there, and carried on farming and animal herding, for over six thousand years after 7,000 BCE, reinforces the belief that it was this that had attracted them; for almost two thousand years the settlement seems to have remained rural; it is only after 4,000 BCE that we see significant signs of urbanisation, peaking around 2,500 BCE.
There are two broad possibilities that suggest themselves as for the origin of the farmers of Mehrgadh: one, they could have come from the sub-Himalayan Gangetic plain which connected to the Greater Indus Valley on the west; or, two, they could have come from across the Bolan Pass, from the foothills of the Zagros Mountains; beyond these mountains lay the Tigres-Euphrates basin, the heart of the Fertile Crescent. Both were populated by early anatomically modern humans. The Out of Africa dispersal by the northern route is supposed to have taken the AMH to what would eventually be the Fertile Crescent, and thence to the Near East [Wurz, 2012: Out Of Africa, The Nile Valley And The Northern Route, in South African Archaeological Bulletin, 67, 169]. On the other hand, the OoA dispersal by the southern route could have taken them to the Gangetic plain and thence to the peninsular India [Forster et al, 2005: Did Early Humans Go North or South, in Science, Vol 308, 965].
At both the places – the Gangetic plain and the foothills of the Zagros Mountains – we have evidence of beginnings of agriculture around 9,000 BCE to 8,000 BCE; a gradual switchover from nomadic hunting-gathering to sedentary settlement and domestication of crops and animals. The first evidence for rice in South Asia comes from the site of Lahuradewa (50 kilometres to the south-east of Gorakhpur) in the eastern Uttar Pradesh, situated on an oxbow pond of Sarayu, a former Ganges tributary. Lahuradewa may have been occupied as early as 9,000 BCE; a direct date on rice confirms the date at 6,400 BCE; rice grains and chaff have been recovered from the early deposits; rice-type phytoliths and an increase in grass-type pollen found in a pollen core were dated to 6,000 BCE. There are, however, no other known sites in the Gangetic plains with such an antiquity; so the early domestication of rice in this region seems to have happened on a very small scale. Domesticated rice associated with this region shares key domestication mutations with East Asian japonica rice[Kingwell-Banham et al, 2015 : Early Agriculture in South Asia, in The Cambridge World History, Vol II, 273]. The beginning of the Neolithic in the eastern India is often placed at 3,500 BCE on the basis of typological similarities with other, better-dated parts of South Asia, though a few radiocarbon dates we have suggest a date of around 2,500 BCE [Kingwell-Banham et al, 2015: 277]. The earliest dates for the Neolithic of south India come from the sites of Kodekal, Utnur, and Watgal and date the earliest Neolithic settlements to 3,000 BCE; dates from Budihal, Brahmagiri and Piklihal place the start of Southern Neolithic at around 2,500 BCE [Kingwell-Banham et al, 2015: 282]. So, the possibility of Mehrgadh farmers having migrated from the east is restricted to just those from Lahuradewa in the eastern Gangetic plain.