A new analysis of the land in the Amazon basin using lidar (technology for measuring distances by emitting light (laser) and measuring the time of return of this reflected light to the receiver - ed.) has revealed a previously unknown urban center of "mind-boggling" complexity.
An article about the discovery was published in the journal Nature.
To be clear, this does not imply the presence of ancient aliens or long-forgotten technology, just that it far exceeds the expected level of organization and population that scientists thought possible for the inhabitants of the Amazon 1,500 years ago.
“No one expected such a society to emerge in this region… pyramids 20 meters high,” said Heiko Prümers of the German Archaeological Institute in a video produced by Nature. “In pre-Hispanic times, the entire region was so densely populated that it is unbelievable. A new civilization, a new culture are waiting for us to study them.”
Until recently, it was thought that only small tribes lived on the Amazon before the arrival of Spanish and Portuguese explorers: a view increasingly challenged by new scientific research. In this case, Prumers was intrigued by mounds called lomas, hidden under vegetation but hinting at something more. Excavations showed that these were not garbage dumps, as some thought, but organized places for burials, ceremonies, and other things indicative of a complex, hierarchical society.
But finding knolls on the ground under the rainforest canopy is far from easy, so in 2019 they decided to scan the area with a helicopter, using lidar to reconstruct surface contours under the trees. Recently, this method proved to be very fruitful: entire Mayan cities and even a kilometer-long artificial earthwork have been discovered in this way.
The lidar beams pass between the leaves and branches, reflecting off them, and give a remarkably detailed view of the height of the ground beneath them. And like never before, this data can be quickly collected and analyzed to produce a three-dimensional point cloud that can easily be checked for hidden structures.
The team discovered more than just a few new scraps: platforms, huge pyramids, defensive structures, reservoirs and canals and more, connecting what appeared to be hundreds of settlements of varying sizes. This contradicts assumptions that the local peoples were nomadic or foraging cultures rather than sedentary and agricultural.
The Kasarabe culture, as it has been called since its discovery, remains largely a mystery. After all, its existence has only recently been confirmed - but it provides a starting point for further research.