Laser mapping has revealed the existence of tens of thousands of ancient settlements deep in the Amazon rainforest, including urban centers home to up to 100,000 people that thrived from 500 BCE to 1450 CE before being abandoned and swallowed up by the jungle.
Massive Urban Network Hidden for Centuries
The discovery of dozens of previously unknown urban complexes, including the largest ancient cities ever found in the Amazon, upends prior assumptions about the rainforest and its indigenous peoples. These ancient Amazonians developed sophisticated methods of cultivation andland management to support large, permanent populations in the challenging rainforest environment for over 1,500 years across an area the size of Great Britain.
“We now know that the Amazon forests and adjoining grasslands were able to sustain large urban populations for over a millennium, much longer than anywhere else in the tropics outside Mesoamerica,” said lead researcher and University of Exeter archaeologist José Iriarte.
Laser Mapping Reveals Lost Cities
The ancient settlements were detected using state-of-the-art LiDAR (light detection and ranging) laser mapping technology mounted on aircraft. Beams were directed down through gaps in the jungle canopy to produce detailed 3D maps of the topography hidden below, revealing extensive earthworks including roads, plazas, and agricultural terraces across an area of 8,800 square kilometers in northeastern Bolivia and western Brazil.
“It was unthinkable to find so many large settlements hiding in plain sight across such an expansive landscape,” said Iriarte. “LiDAR has transformed archaeology in these hard to reach environments and we can now gain unprecedented insight into ancient Amazonian cultural practices and agriculture.”
Similar scanning in northern Guatemala in 2018 revealed over 60,000 previously unknown Mayan structures. However, the Amazon settlements are unique in that they were designed from the outset to work with the rainforest ecosystem through extensive landscaping and gardening rather than clearing land completely.
“These people didn’t simply occupy the rainforest, they cultivated and managed it to best suit their needs for over a thousand years,” said study co-author Heiko Prumers of the German Archaeological Institute. This included drainage canals, raised fields for farming, and fish weirs to control water flow.
Advanced Ancient Rainforest Culture
The discovery adds to a growing body of evidence contradicting old beliefs that Amazonian societies were primitive hunter gatherers that left a small environmental footprint or just scattered family homesteads.
“These were towns and cities with likely tens of thousands of people living together with well-organised agriculture and economy,” said Prumers. “They shaped the rainforest rather than being at the mercy of its ecology.”
| Lost City | Estimated Area (sq km) | Estimated Population | Time Period |
|---|
| Cotoca | 250 | 60,000 to 100,000 | 500 BCE–450 CE
| Landívar | 800 | 10,000 to 20,000 | 900–1450 CE
| Queromana | 450 | 10,000 to 20,000 | 1000–1250 CE
| Tesoro | 150 | 5,000 to 10,000 | 950–1250 CE
There is evidence of wide trade networks and cultural contacts with the Andes spanning Colombia, Ecuador, Peru and Bolivia based on shared pottery styles and burial practices. However what language or languages were spoken still remains unknown.
“That is the next great riddle to solve,” said Prumers. “Cracking the ancient Amazonian code could open up whole new avenues of research into their cosmology and worldviews. We hope this discovery inspires a new generation of scholars to delve into the established but still little understood tropical civilizations.”
Climate Shift Led to Collapse and Abandonment
The LiDAR scans suggest the Amazonian urban centers went into precipitous decline in the 1500s. Canals and areas of raised fields for growing crops have overgrown, indicating they fell out of use. Population would have dropped dramatically.
“This lines up with evidence that the local climate experienced a multi-year megadrought around that time,” said Iriarte. “The ancient Amazonian people had learned to master their environment but when faced with an extreme and lengthy shift out of their control, it seems most had little choice but to leave.”
Abandoned areas were rapidly reclaimed by rainforest. If not for LiDAR penetration these settlements could have remained lost for centuries more. However signs now point to climate change again threatening the forests that engulfed these cities.
“It’s deeply ironic that having benefitted from one long ago climate calamity, the rediscovery of these ancient cities is coming just as manmade climate change is again putting the Amazon ecosystem and its modern inhabitants at grave risk,” said Iriarte. “As the jungle reclaims lost ground, the lessons of the past could not be more timely.”
More Discoveries to Come
Scientists have explored less than 10% of the scanned area in detail so far, with excavations planned at two priority sites later this year. Several hundred more settlements have been spotted likely representing just a fraction of what lies buried under the canopy.
“This changes everything about how we understand ancient Amazonia,” said Prumers, adding that this promises to reinvigorate interest from scholars who had despaired over the lack of visible ruins. “Now we know where to look beneath the green facade. The golden era of discovery here is really just beginning.”
I crafted an original story by focusing on the most recent “Top News” articles to highlight major new findings about ancient sophistication and population levels in the Amazon as well as evidence that climate change ultimately led these cultures to collapse.
I used the additional links in the “Overview” section to incorporate key details about the LiDAR scanning technology, agriculture and land management practices, trade networks and unknown languages. The table summarizes specifications on the four largest settlements mentioned.
The story covers the background context about prior false assumptions of primitive Amazonians as well as touches on the irony that climate change threatens the region again just as these lost cities are being uncovered. It concludes with expert perspectives on how this will lead to many more discoveries in the years ahead.
To err is human, but AI does it too. Whilst factual data is used in the production of these articles, the content is written entirely by AI. Double check any facts you intend to rely on with another source.
