The idea of a “lost city” may feel like an ancient legend or the plot of a movie, but some of the world’s abandoned cities were bustling not too long ago. In France, the town of Oradour-Sur-Glane has been mostly untouched since 1944, when a military branch of the Nazi Party’s SS organization killed most of its population. Italian city Craco’s population dwindled after landslides in the 1960s and was completely deserted after an earthquake in 1980. The landscape of the western United States is full of the boom and bust towns that cropped up during the 19th Century.
It’s obvious that cities rise and fall, but there often aren’t clear records of why—especially when studying urban areas from thousands of years ago. Archaeologists face the challenge of putting together a puzzle from the remains of cities long gone to form theories of why some places retained their importance longer than others.
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A study published on March 3 in the journal Frontiers in Ecology and Evolution analyzed the remains of 24 ancient cities in present-day Mexico and found that collective governance, investments in infrastructure, and cooperation between households were consistent in the cities that lasted the longest.
“For years, my colleagues and I have investigated why and how certain cities maintain their importance or collapse,” said study co-author Gary Feinman, the MacArthur Curator of Anthropology at the Field Museum in Chicago, in a statement.
Previously, the team surveyed a wide range of Mesoamerican cities over thousands of years. They found a broad pattern of societies with government structures that promoted the well-being of its people that lasted longer than the ones with large wealth gaps and autocratic leaders.
Their new study focuses more on cities from a smaller time and geographical scale. The 24 cities in the western half of Mesoamerica and were founded between 1000 and 300 BCE, centuries before Spanish colonization dramatically changed the region in the 16th century.
Clues were found in the remains of the buildings, ground plans, monuments, and plazas. “We looked at public architecture, we looked at the nature of the economy and what sustained the cities. We looked at the signs of rulership, whether they seem to be heavily personalized or not,” said Feinman.
If remnants contain art and architecture that celebrates larger-than-life rulers, it’s a sign that the society was more autocratic or despotic. By contrast, depictions of leaders in groups, often wearing masks, is more indicative of shared governance.
Among the 24 ancient cities in the study, the cities that had more collective forms of governance tended to remain in power longer, sometimes by thousands of years more than the more autocratic ones.
[Related: The ancient Mexican city of Monte Albán thrived with public works, not kings.]
However, even among the cities that were likely governed well, some cities were still outliers. To understand why, they looked at infrastructure and household interdependence.
“We looked for evidence of path dependence, which basically means the actions or investments that people make that later end up constraining or fostering how they respond to subsequent hazards or challenges,” Feinman said.
They found that efforts to build dense and interconnected homes and large, central open plazas were two factors that contributed to sustainability and regional importance of these cities.
As a way to measure sustainability in the past, most research looks for correlations between environmental or climatic events like hurricanes and earthquakes and the human response to them. However, it’s difficult to know whether the timing is reliable, and these studies typically emphasize a correlation between environmental crisis and collapse without considering how some cities successfully navigated those major challenges.
In this study, the team took a different approach. The residents of these cities faced everything from drought and earthquakes to periodic hurricanes and heavy rains, in addition to challenges from competing cities and groups. They used this lens to examine the durational history of the 24 centers and the factors that promoted their sustainability. The team found that it was governance that had an important role in sustainability. According to study co-author Linda Nicholas, this shows that, “responses to crises and disasters are to a degree political”. Nicholas is an adjunct curator at the Field Museum.
While these cities and their inhabitants have been gone for thousands of years old, the lessons learned from their peaks and downfalls are incredibly relevant today.
“You cannot evaluate responses to catastrophes like earthquakes, or threats like climatic change, without considering governance,” said Feinman. “The past is an incredible resource to understand how to address contemporary issues.”