LiDAR reveals vast Aquiry civilization

Researchers led by Martti Pärssinen of the University of Helsinki used airborne LiDAR scanning to survey about 4,500 square kilometers of rainforest in Brazil's Acre state. They identified 432 earthworks, including 396 previously unknown sites, consisting of geometric ditches and embankments. Extrapolating across the Aquiry civilization's estimated 183,000 square kilometer territory, they estimate 20,000 to 30,000 earthworks may exist. Radiocarbon dating and surveys suggest the civilization, which flourished from 600 BCE to 850 CE, supported 1.25 to 3 million people at its peak. The findings challenge previous assumptions about pre-Columbian Amazon population and human impact on the rainforest, including evidence of forest management and cultivation of species like Brazil nut and peach palm. The study was published in the journal Nature.