Societies in Mesoamerica and Southeast Asia whose collapse was thought to have been caused by dramatic changes in climate displayed more resilience and adaptability than previously believed, according to a new study in the Proceedings of the National Academy of Sciences.
In the study, researchers at The University of Texas at Austin and the University of Sydney compared the collapse of the Maya civilization in the eighth-11th centuries A.D. — in what is now Belize, Guatemala, El Salvador, Honduras and Mexico — with the Khmer empire collapse of the 14th-15th centuries A.D.— located in modern Cambodia, Thailand, Vietnam and Laos.
Using soil samples and archaeological evidence from the two civilizations, the researchers found that both sites experienced significant transformation of the natural environment in the form agriculture and water management systems during their prime. However, while the decline of Maya urban centers was probably brought on by droughts, the decline of the Khmer urban center of Angkor preceded that region’s climate stresses by more than a century.
In both cases, even as urban centers declined, the surrounding developed forest settlements persisted. The authors argue that their survival was probably due to indigenous agricultural innovations that created soil systems that were both more conducive to farming and more resistant to climate fluctuations.
“The Maya and peoples of the Angkor built massive, elaborate temple complexes, water systems and intensive farming systems that equaled or bested those of the West at comparable periods,” said the study’s co-author, Timothy Beach, professor in the Department of Geography and the Environment at UT Austin. “This work upscales the growing evidence that shows the global tropics have long been humanized landscapes, which is turning over the ingrained belief that tropical forests are pristine and natural.”
The authors suggest that population migrations away from urban centers may represent adaptation to climate variability rather than abandonment of cities destroyed by unchecked transformation of natural landscapes, as proposed by previous narratives about societal collapse.
“This is a revolution in archaeological and ecological understanding of the tropics,” Beach said. “We leverage geoarchaeological evidence with archaeological evidence from artifacts and texts to compare how these cultures were resilient to ecological and climate changes for long periods.”
The authors note that nearly half of the Earth’s population currently lives in the tropics and that the urbanization of these regions — which includes profound transformation of forests and a tendency toward low-density cities — mirrors the earlier civilizations explored in the study.