Human faces and other figures carved in stone up to 2,000 years ago have been discovered on the banks of the Amazon River, as a historic drought in the Brazilian region brought water levels to unprecedented lows.
The petroglyphs, depicting animals and other natural forms, were discovered on the banks of the Rio Negro at an archaeological site known as Ponto das Lajes, or Site of the Plates.
Researchers estimate the markings are between 1,000 and 2,000 years old.
The sculptures were previously spotted during a severe drought in 2010, when the water level of the Rio Negro fell to 13.63 meters, a record low at the time.
They resurfaced this month, and as the water receded more marks appeared. Amid an unusually dry season that scientists attribute to the El Niño weather pattern and warming associated with climate change in the North Atlantic, the Rio Negro has sunk below 13 meters for the first time ever, with a depth of 12.89 meters recorded on Monday.
Archaeologist Jaime de Santana examines ancient tool sharpening marks on Amazon rocks that were exposed by falling water levels during the drought in Manaus. Photo: Suamy Beydoun/PortalIn addition to anthropomorphic faces and depictions of water, some rocks also have grooves indicating that stone tools were also made at the site.
Carlos Augusto da Silva of the Federal University of Amazonas identified 25 groups of carvings on a single rock, which he said was used as a whetstone for sharpening various instruments. “This was a tool preparation area,” the archaeologist told local news site Amazônia Real.
Ceramic fragments believed to be thousands of years old were also reportedly found at the site, which was home to large indigenous villages in pre-Columbian times.
Although the Ponto das Lajes petroglyphs are designated as an archaeological site, they have not been studied, and researchers estimate their age based on similar petroglyphs in other parts of central Amazonia.
“These places, now archaeological sites with black earth, large amounts of ceramic fragments and rock carvings, tell the ancient indigenous history of the region and must be treated with respect by all of us who live in Manaus today,” said archaeologist Filippo Stampanoni Bassi Amazonia Real.