the broader Indus Valley Tradition into four eras, the pre-Harappan "Early Food Producing Era", and the Regionalisation, Integration, and Localisation eras, which correspond roughly with the Early Harappan, Mature Harappan, and Late Harappan phases. Pre-Harappan era: Mehrgarh Mehrgarh is a Neolithic (7000 BCE to c. 2500 BCE) mountain site in the Balochistan province of Pakistan, which gave new insights on the emergence of the Indus Valley Civilisation. Mehrgarh is one of the earliest sites with evidence of farming and herding in South Asia. Mehrgarh was influenced by the Near Eastern Neolithic, with similarities between "domesticated wheat varieties, early phases of farming, pottery, other archaeological artefacts, some domesticated plants and herd animals." Jean-Francois Jarrige argues for an independent origin of Mehrgarh. Jarrige notes "the assumption that farming economy was introduced full-fledged from Near-East to South Asia," and the similarities between Neolithic sites from eastern Mesopotamia and the western Indus valley, which are evidence of a "cultural continuum" between those sites. But given the originality of Mehrgarh, Jarrige concludes that Mehrgarh has an earlier local background, and is not a "'backwater' of the Neolithic culture of the Near East". Lukacs and Hemphill suggest an initial local development of Mehrgarh, with a continuity in cultural development but a change in population. According to Lukacs and Hemphill, while there is a strong continuity between the neolithic and chalcolithic (Copper Age) cultures of Mehrgarh, dental evidence shows that the chalcolithic population did not descend from the neolithic population of Mehrgarh, which "suggests moderate levels of gene flow." Mascarenhas et al. (2015) note that "new, possibly West Asian, body types are reported from the graves of Mehrgarh beginning in the Togau phase (3800 BCE)." Gallego Romero et al. (2011) state that their research on lactose tolerance in India suggests that "the west Eurasian genetic contribution identified by Reich et al. (2009) principally reflects gene flow from Iran and the Middle East." They further note that "[t]he earliest evidence of cattle herding in south Asia comes from the Indus River Valley site of Mehrgarh and is dated to 7,000 YBP." Early Harappan The Early Harappan Ravi Phase, named after the nearby Ravi River, lasted from BCE until 2800 BCE. It started when farmers from the mountains gradually moved between their mountain homes and the lowland river valleys, and is related to the Hakra Phase, identified in the Ghaggar-Hakra River Valley to the west, and predates the Kot