Discovered previously unknown ruins of an 'ancient city' in the Amazon hinterland by LIDAR survey from above



The existence of an 'ancient city' covered in the rainforests of Bolivia, South America, was revealed by a

Light Detection and Ranging survey using a laser scanner mounted on a helicopter. It is believed that the people who built the ancient cities had a fairly high civilization, building networks of roads and canals around huge pyramids, farming and farming fish.

Lidar reveals pre-Hispanic low-density urbanism in the Bolivian Amazon | Nature
https://doi.org/10.1038/s41586-022-04780-4

Large-scale early urban settlements in Amazonia
https://doi.org/10.1038/d41586-022-01367-x

Forgotten Ruins of'Monumental' Amazonian Settlements Discovered in Bolivian Jungle
https://www.sciencealert.com/ruins-of-monumental-settlements-uncovered-in-bolivian-jungle

Lasers reveal'lost' pre-Hispanic civilization deep in the Amazon | Live Science
https://www.livescience.com/lidar-reveals-pre-hispanic-amazon-settlements

The research conducted by international research teams in Germany and the United Kingdom aimed to find the remains of the ancient Casarabe culture in the area of Lianos de Mojos (Mohos) in Beni Department, northeastern Bolivia. .. Regarding the ancient Casarabe culture, which seems to have prospered around 500 to 1400, although some ruins have been discovered so far, it seems that large-scale civilizations and cities cannot be maintained in the poor tropical soil of Llanos de Mojos. It was said that it was.

Using LIDAR on board a helicopter, the research team scanned six areas spanning a total of 204 square kilometers, believed to be the center of ancient Kasarabe culture, looking for traces of ruins hidden under the rainforest. As a result, a vast network of two large archaeological sites and 24 small archaeological sites was discovered, and it was also found that these networks were connected by roads. The existence of two large archaeological sites called 'Cotoca' and 'Landívar' and 15 small archaeological sites has been known for some time, but nine small archaeological sites have been discovered for the first time.

This is the LIDAR data of Cotoca with a color indicating the height difference. You can see that the city was built in a place where the land was raised over a wide area, and a pyramid of up to 22 m rises in the center. People of ancient Kasarabe culture are believed to have moved 570,000 cubic meters of soil in the construction of Cotoca, suggesting that the people at that time had advanced civil engineering and construction techniques. Both Cotoca and Landívar have a pyramid, and it is certain that they had some religious worldview, but the details are unknown.



Cotoca and Landívar were central hubs of a regional network of roads, reservoirs and canals, with roads and waterways radiating out. This shows the landscape and labor management in ancient Kasarabe culture. Even the 24 small settlements outside the large settlements could have been inhabited by thousands of people each. 'You can reach another settlement in just an hour's walk,' said Heiko Prümers, an archaeologist at the University of Bonn, Germany, who is the lead author of the paper. It shows that it was expensive, 'he told the scientific media Live Science.



Lianos de Mojos is a lowland tropical savanna, and although it does not rain at all during the dry season, most of it is flooded during the rainy season from November to April. It is believed that ancient Kasarabe culture managed seasonal floods through canals and reservoirs, cultivated corn and other crops in uplifted areas, and may have cultivated fish in some reservoirs.

It is believed that the ancient Kasarabe culture declined around 1400, more than 100 years before the Spanish settling began. Prümers speculates that the reason may be that climate change has disrupted the rainy season-dependent water management system, causing water shortages.

The results of this study deny the theory that there were only sparse settlements in the western Amazon before Spanish rule, and showed a highly integrated and dense settlement system of ancient Kasarabe culture and a hierarchical and complex social system. It shows that you had it.

Following the findings, Colorado State University archaeologist Christopher Fisher is now able to collect data from once harsh fieldwork for several years in a single flight with LIDAR. Pointed out that it has become. However, he argued that the ancient relics found in the field survey are still important clues to the past and need to be investigated before the archaeological evidence is completely gone.

in Science, Posted by log1h_ik