Interview with Dr Cameron Petrie, University of Cambridge, who is the lead author of the study 'Current Anthropology'
Was the finding of summer rain and crops around the year your ‘exclusive’?
Scholars have long argued that the Indus Civilisation developed in a region that was affected by winter and summer rain, and also that Indus farmers grew a diverse range of crops (e.g. Vishnu-Mitre, Chakrabarti, Weber). However, our understanding of the dynamics of those rainfall systems and their impact upon farming has been somewhat simplistic, and many of the details of the diversity in cropping have not been demonstrated archaeologically.
For our paper, we have mapped the distribution of rainfall over the last century as a way of understanding rainfall patterns in the past. We have also conducted extensive analysis of crop use in NW India, and discovered (among other things) the very early use of rice, and also clear evidence for diverse cropping practices at different settlements at the same time within one area. This diversity suggests that ancient farmers were constantly making choices about what to grow, and were thus adapted to a variable environment/climate.
What are the key findings of this study?
The Indus population was adapted to living in a variable and changing environment, and this saw a considerable degree of variation in the farming practices, and also in their cultural behaviour. Therefore, we argue that they were well suited to being resilient to climate change, and suggest that they were able to respond to changes in their environment. There is clear evidence for both local production of pottery, and also trade and exchange in various other elements. We describe this situation as ‘predictable unpredictability’ – borrowing a phrase from Naomi Miller, who used it to describe a period in the Bronze Age in Turkey.
Since you have looked at only one area, how do you establish that Indus people knew to deal with climate change?
We have evidence for weakening of the monsoon from Kotla Dahar, which is close to Delhi, and this evidence matches what has been seen in caves in NE India and Oman. However, there is still a lot to learn about ancient climate and weather pattern in the subcontinent.
We are very careful to argue that it would be unwise to extrapolate the findings from our study area in NW India and generalise about the whole region. We argue that climate change is likely to have had an extremely variable impact across this area especially because of the pre-existing diversity in the climate and environment.
It appears that in dealing with climate change, Indus population displaced (moved) away from some areas and more densely occupied other areas, which presumably had more reliable rainfall. This is not simply a move east, as it has often been described, but actually a specific move into a region that potentially received rain even when the monsoon was weak. They appear to have maintained and/or increased the diversity of their farming practices, and at least in some areas, they appear to have de-urbanised and expanded the rural population.
Did they react to environment change differently than modern societies?
It is difficult to draw parallels to the modern context because the size of modern population is much higher, and modern agriculture operates at a different scale and intensity. A simplistic view could point that past farming appears to have been intense and relatively small-scale, focusing on a diverse range of crops used to feed a modest population. Indus populations appear to have lived in a range of different situations with different access to water.
In contrast, modern farming in NW India is extensive, and focused on a small number of crops, feeds a larger population, and also produces a surplus – all critical elements of the green revolution. However, modern farming also involves extensive use of fertilisers and pumping of sub-surface water, and the latter is resulting in extreme depletion of the water table. Although extremely productive, modern practices are definitely having an impact on the local environment, and it is important to consider whether it will be resilient to changes in the environment.
What is the most striking thing about the Indus people’s adjustment with climate change?
We hope to reinforce the view that the Indus Civilisation did not collapse in the typical sense of the word, but underwent a gradual transformation. This is not a new idea, but the frame that we have chosen for interpretation is different. We argue that climate change played a role, but other factors were also important. Our evidence for diversity in cultural behaviour – particularly in crops and farming practices – lead us to hypothesise that Indus populations were well suited to be resilient to periods of climate change.
What questions does this study raise? And how do you plan to take it forward?
The study raises a lot of questions – particularly about the diversity of the rainfall systems affecting the regions, possible diversity in the climate evidence from the past, the nature of the hydrological systems in the region, the nature and distribution of settlement in the region, the nature of ancient landscapes and soilscapes, foods that Indus populations were actually eating, the way Indus populations produced their pottery, and also the details of the way that they actually responded to change – particularly in terms of the decision making processes. All of these questions are being funded by the European Research Council project entitled TwoRains.
(The interview appears in the March 1-15, 2017 issue of Governance Now)