Excavations suggest that climate change may have contributed to the rise and fall of many ancient civilizations
By Kiran N. Kumar
Archaeologists have nailed down the turmoil behind the collapse of the prehistoric Maya city in Mexico to an extended period of drought, unleashed by climate change, reflecting similar findings elsewhere about the demise of ancient civilizations.
In Maya, between 1441 and 1461 CE, the social and political strife reached a crescendo — suggesting that climate change-induced drought may have stoked the civil conflict that triggered violence.
Read: Disappearing islands: inevitable climate change phenomenon (July 29, 2022)
This in turn led to the collapse of institutions, instability and eventual extinction, according to new research by anthropologist and professor Douglas Kennett of University of California Santa Barbara and his team of experts from the fields of archaeology, history, geography and earth science.
The researchers examined archaeological data, including isotope records, radiocarbon data and DNA sequences from human remains, to document an interval of unrest between 1400 and 1450 CE. They then used regional sources of climatic data and combined it with a newer, local record of drought from cave deposits beneath the city.
“Existing factional tensions that developed between rival groups were a key societal vulnerability in the context of extended droughts during this interval,” Kennett said.
The vulnerabilities revealed in the data were rooted in Maya reliance on rain-fed maize agriculture, a lack of centralized, long-term grain storage, minimal investments in irrigation and a sociopolitical system led by elite families, said Kenneth.
Yet, they adapted and persisted into the early 16th century before extinction, reflecting the complexity of human responses to drought on the Yucatan Peninsula where Mayan Civilization lasted, said the authors.
Other civilizations & climate change
The latest technology, innovations and combinations from satellite imagery or remote sensing data to DNA analysis, have helped anthropologists and archaeologists to see the impossible beneath the ground and find links between climate change and the collapse.
In the case of the Maya and other lost cities in Central and South America, the massive Amazon jungle quickly grew over ancient buildings obscuring structures, until scientists discovered them in satellite imagery about differences in vegetation patterns to locate them.
Even the fabled city of Ubar came to light when NASA’s Jet Propulsion Laboratory (JPL) in 1982 initiated the search using computers to enhance images taken in the visible and infrared wavelengths, as well as with radar.
They were able to peer up to 15 feet beneath the surface of dry sand to analyze the sizes and proportions of dust, rocks and sand grains, besides the city boundaries and roads.
“When we excavate the remains of past civilizations, we very rarely find any evidence that they as a whole society made any attempts to change in the face of a drying climate, a warming atmosphere or other changes. I view this inflexibility as the real reason for collapse,” says Dr. Jason Ur of Harvard University.
Read: Drought-Induced Civil Conflict Among the Ancient Maya (July 19, 2022)
Finally, the excavations are turning up more evidence that changes in climate – both large and small – are at least partly responsible for the rise and fall of many ancient civilizations.
Now that droughts have been linked to the fall of the Maya around 900 AD, so was the demise of the spectacular Cambodian city of Angkor in the early 1400s or the Egypt Civilization 4,200 years ago.
Since our way of life depends on a stable climate, it’s time for modern humans to learn the lessons of past collapsed civilizations and adapt better to survive into the future.