Overview
- The Nature paper, which appeared July 29, reported nearly 400 previously undocumented geometric earthworks found by a 1,740-square-mile airborne lidar survey in the southwestern Amazon.
- From those mapped sites the authors extrapolated a regional total of about 23,000–30,000 earthworks and estimated an Aquiry population of roughly 1.25–3 million across some 70,600 square miles, figures well above earlier counts.
- The mapped features are large formal constructions—circles, squares, octagons and complex shapes—with average sites near seven acres and some as big as 123 acres, with ditches up to about 40 feet wide and 16 feet deep.
- Independent archaeologists praised the scale of the lidar mapping but stressed the population and regional totals are provisional and require targeted ground-truthing through excavation, radiocarbon dating and searches for nearby occupational sites.
- If validated, the findings would strengthen the view that precolonial peoples extensively shaped Amazon landscapes, with consequences for how researchers estimate past biodiversity, carbon storage and the protection of Indigenous heritage threatened by deforestation.