Lacking fullest data, there is, nonetheless, a growing consensus that Harappan culture is the result of indigenous cultural developments, with no “Me… - Jim G. Shaffer

While lacking fullest data, there is a growing consensus that the Harappan culture originated as a result of local cultural developments. "Mesopotamian" inventions are not needed to explain it.

The previous concept of a Dark Age in South Asian archaeology is no longer valid.... [we have a] cultural continuum stretching from perhaps 7000 BC into the early centuries AD...

“No material culture is found to move from west to east across the Indus”. [in the relevant time period]

Pollen cores from Rajasthan seem to indicate that by the mid-third milennium BC, climatic conditions of the Indus Valley area became increasingly arid. Data from the Deccan region also suggests a similar circumstance there by the end of the second millennium BC. Additionally, and more directly devastating for the Indus Valley region, in the early second millennium BC, there was the capture of the Ghaggar-Hakra (or Saraswati) river system (then a focal point of human occupation) by adjacent rivers, with subsequent diversion of these waters eastwards. At the same time, there was increasing tectonic activity in Sindh and elsewhere. Combined, these geological changes meant major changes in the hydrology patterns of the region. These natural geologic processes had significant consequences for the food producing cultural groups throughout the greater Indus Valley area. Archaeological surveys have documented a cultural response to these environmental changes creating a “crisis” circumstance...