
Archeologists uncovered nearly 400 previously unknown ancient earthworks beneath the southwestern Amazon rainforest, revealing what is believed to be evidence of complex societies that flourished long before Spanish and Portuguese colonists arrived. The findings, published this week in the journal Nature, identified circles, squares, and other geometric formations that archeologists call geoglyphs dating from 600 B.C. to 850 A.D. using lidar, a laser-scanning technology capable of seeing under dense forest canopy. Sprawling across 1,700 square miles, the newly uncovered structures add to mounting evidence that the Amazon basin was once home to vast, densely populated societies centuries before Columbus. “This is an important and ambitious study... which reveals the remarkable scale of pre-Columbian landscape modification in southwestern Amazonia,” said José Iriarte, an archeologist at the University of Exeter who was not involved in the research. Lead author Martti Pärssinen told The New York Times that the earthworks likely hosted “festivities, political occasions, ceremonies, dance, music and also competition like ball games.” Anna Roosevelt, a professor of anthropology at the University of Illinois Chicago who was not part of the research team, told the paper, “Nobody has totally figured out” the exact purpose or meaning of the geoglyphs.
















