The Land, Water, Settlement project, a collaboration between the University of Cambridge and Banares Hindu University, laid the foundations for the work we are doing on the TwoRains project. Between 2007 and 2014 the Land, Water, Settlement project worked in northwest India, exploring how the Indus Civilization coped with variable and changing environments. The results of this research have been integrated in an article published online today (27th January 2017) in the journal Current Anthropology. The article discusses how Indus populations in north‐west India interacted with their environment, and considers how that environment changed during periods of climate change.

The Land, Water, Settlement project and the TwoRains project are both interested in the Indus Civilization as it provides a unique opportunity to understand how an ancient society coped with diverse and varied ecologies, and change in the fundamental and underlying environmental parameters. Compared to other early complex societies the Indus Civilization developed under unusual environmental conditions. Most early complex societies developed in regions where the climatic parameters faced by ancient subsistence farmers were varied, but not especially diverse. The Indus Civilization developed in a specific environmental context, where the winter and summer rainfall systems overlapped. There is now evidence to show that this region was subject to climate change during the period when the Indus Civilization was at its height (c.2500‐1900 BC).

Distribtion of urban-phase Indus settlements (upper image) and post-urban-phase Indus settlements (lower image) in north-west India and their relationship to mean annual rainfall (1900-2008). Major Indus sites and sites investigated by the Land, Water, Settlement project are shown in white. Image credit: C. Petrie

From Kotla Dahar, a lake adjacent to the area occupied by Indus populations, the Land, Water Settlement project discovered evidence for two dramatic decreases in monsoon rainfall and a progressive lowering of the lake level. The second of these shows Kotla Dahar becoming completely ephemeral ca. 2200–2000 BC as a result of an abrupt weakening of the monsoon, and the weakening of the monsoon is visible in speleothem records in Oman and northeast India. The proximity of the Kotla Dahar record to the area occupied by Indus populations shows that climate must be formally considered as a contributing parameter in the process of Indus deurbanization, at least in the context of the plains of northwest India.

It has long been hypothesized that there was variation in the subsistence practices used by Indus populations and this fits with the theme of coping with diverse environments. In this article, the Land, Water, Settlement team argue that rather than being forced to intensify or diversify subsistence practices in response to climatic change, millet, rice and tropical pulses were already in use in the pre‐urban and urban phases of the Indus Civilization. This evidence suggests that local Indus populations were already well adapted to living in varied and variable environmental conditions before the development of urban centers. It is also possible that these adaptations were beneficial when these populations were faced with changes to the local environment that were probably beyond the range of variation that they typically encountered.

The TwoRains project will be building on this research to ask ‘does climate change really cause collapse?’ and will be expanding the discussion of human‐environment interactions and their relationship to processes of cultural transformation. Check back soon and follow us @TwoRains on Twitter for updates!

To read the full article click here