Cutting-edge technology has revealed the Amazonian rainforest hides thousands of records of ancient indigenous communities under its canopy, according to a study published in the journal Science.
James Cook University's Distinguished Professor Bill Laurance, a long-time Amazon expert, took part in the study. He said the Amazon is the world's most diverse forest and according to the new study may also host more than 10,000 records of pre-Columbian earthworks - constructed prior to the arrival of Europeans.
"Anthropologists have debated for decades about whether ancient peoples lived throughout the Amazon Basin, or only along its drier fringes," said Professor Laurance.
"Our study—which combines cutting-edge remote sensing with archaeological data and advanced statistical modelling to identify hidden earthworks—suggests there were more native people living in the Amazon than many had imagined.
"But they mostly lived in drier, more fertile areas where farming and forest burning was suitable," said Professor Laurance.
The study was conducted by a team of 230 researchers from 24 countries across 4 continents. It was led by Brazilian researchers Vinicius Peripato, a doctoral student in Remote Sensing at Brazilian National Institute for Space Research.
The team of scientists identified new archaeological sites using a laser-based sensor mounted on an aircraft. This sensor allows for reconstruction of a highly detailed 3D model of the land surface beneath the dense forest canopy.
The researchers were impressed with the sophistication of some of the earthworks and irrigation works they discovered.
"These peoples mastered sophisticated techniques for land and plant management. In some cases, those techniques are still known to present-day communities and could inspire new ways to coexist with the forest without the need for its destruction," said Carolina Levis from the Federal University of Santa Catarina in Brazil.
This groundbreaking study also has political implications for the current debate on indigenous land demarcation in Brazil.
"This research provides numerous pieces of evidence of the ancestral occupation of the Amazon rainforest by indigenous peoples, their ways of life, and the relationship they established with the forest," the authors said.
Paper: "More than 10,000 Pre-Columbian earthworks are still hidden throughout Amazonia" by Vinicius Peripato et al in Science.
