Using laser technology, archaeologists have uncovered evidence of a huge, lost civilization that once flourished beneath the canopy of the Amazon rainforest, completely changing what we knew about the region's history.
The research team from the University of Helsinki discovered more than 400 previously unknown earth structures, hidden under trees, using LiDAR technology, which fires laser pulses through vegetation to create an accurate map of what the ground hides.
It is estimated that the ancient Aquiry civilization, which constitutes only 3% of the greater Amazon region, controlled an area of approximately 183,000 square kilometers (71,000 square miles), built at least 20,000 earthworks throughout the region, and was home to between 1.25 million and 3 million people at the beginning of the first millennium AD.
These settlements included political and religious centers connected by a wide network of straight roads and elevated bridges, revealing a sophisticated and organized society, not just isolated villages as previously thought.
Professor Martti Parsennen, the study's lead author, said: "Our findings overturn our understanding of the Amazon' past, and show that human impact on its environment has been far greater than previously thought."
According to the oral traditions of the indigenous people, these centers were built to foster relationships between communities, and were used for rituals, trade, feasts and community events. The celebrations included dancing, music, sports competitions and ball games.
To build these structures, the Akiri people dug deep trenches and piled soil into high dams to form huge circles, squares, rectangles and octagons, some of which were hundreds of meters wide.
They also burned parts of the forests to clear the land for ceremonial centers and fields of corn and gourds, while practicing horticulture and managing valuable trees.
Researchers point out that this civilization was not a single kingdom, but a network of many different societies. It is unknown what languages they spoke or what they called themselves, and the reason for its rapid collapse around 850 AD remains a mystery.
The team emphasizes that only a tiny fraction of the rainforest has been surveyed with LiDAR technology so far, meaning that thousands of settlements and other earthworks may still be hidden under the green canopy. If similar results are found in other parts of the Amazon, it may require a reassessment of pre-colonization population density and its impact on soil, biodiversity, and even global climate models.
