The civilization of Angkor in what is now Cambodia thrived for centuries before it went into relatively sudden decline and collapsed. Across the world the Mayan civilization experienced a similar trajectory in Mesoamerica round about the same time.
Yet even as these iconic civilizations collapsed between 900 CE and 1,500 CE, others in their respective regions continued to flourish.
Now a team of scientists say they might have an answer as to why that happened: climate resilience, or rather lack thereof. The collapse of the Angkor and Mayan civilizations occured during periods of intense climate variability, which triggered mass exoduses from populated urban centers and led to social collapse, they note.
“Large, low-density settlements of the tropical world disintegrated during the first and second millennia of the CE. This phenomenon, which occurred in South Asia, Southeast Asia, and Mesoamerica, is strongly associated with climate variability and extensive landscape transformation,” the scientists explain in a study.
“These profound social transformations in the tropical world have been popularized as ‘collapse,’ yet archaeological evidence suggests a more complex and nuanced story characterized by persistence, adaptation, and resilience at the local and regional scales,” they elucidate.
People living in less populous communities endured and the reason for that, the scientists posit, lies in their lifestyles, which were more suited to their environment and enabled them to respond better to changing climates and agricultural conditions.
These new conditions and locals’ response to them could support smaller communities of farmers but not larger urban populations of priests, aristocrats and other elites.
“[These communities] created extensive landscapes of terraced and bunded (embanked to control water flow) agricultural fields that acted as massive sinks for water, sediment and nutrients,” says Daniel Penny, an associate professor at the University of Sydney’s School of Geosciences who was lead author of the study.
“This long-term investment in soil fertility and the capture and storage of water resources may have allowed some communities to persist long after the urban cores had been abandoned.”
In the city of Angkor people started abandoning their civilization’s administrative and ceremonial center over a period of several decades during a series of devastating droughts in the 14th and 15th centuries before the entire civilizational core was finally left to the jungle. Yet people in surrounding agricultural areas could well have weathered these periods of intense climatic stress and carried on living in smaller communities.
In other words, different degrees of climate resilience could account for why highly organized and stratified civilizations collapsed and less populated rural communities survived.
“Divergences between vulnerable urban elite and apparently resilient dispersed agricultural settlements sit uncomfortably with simplistic notions of social collapse and raise important questions for humanity as we move deeper into the Anthropocene,” the scientists observe.
There are lessons we can draw from this fact as we are facing the devastating impacts of climate change ourselves. “We often think of these historic events as disasters, but they also have much to teach us about persistence, resilience and continuity in the face of climate variability,” Penny argues.
