Researchers have identified 303 previously uncharted geoglyphs made by the Nazca civilization in Peru with the help of machine learning, including figurative representations of humanoid figures resembling aliens, domestic animals, fish, birds, and cats.
Most of the new finds were discovered with the help of AI and drones, allowing researchers to analyze extensive geospatial data and identify high-probability sites for undiscovered geoglyphs. The findings mark the culmination of a six-month field survey by Yamagata University, resulting in a "16-fold increase in the discovery rate."
The research team, led by Masato Sakai of Yamagata University, examined 1,309 locations using an AI system called ResNet50, trained to recognize patterns in high-resolution aerial images. "Artificial intelligence was able to eliminate 98 percent of the images," Marcus Freitag, a physicist at IBM who collaborated on the project, said, The New York Times reports. "Finding the needle in the haystack becomes practically impossible without the help of automation," he added.
To identify the new geoglyphs, the researchers used an application capable of discerning contours from aerial photographs, no matter how faint, The New York Times reports. The AI software generated a list of 303 figures and suggested more than 47,000 potential sites, with 1,309 identified as high potential, but so far, only 26% of the areas proposed by the AI have been studied.
Between September 2022 and February 2023, the researchers conducted a field expedition on the ground, scouting the more promising locations by foot and with drones. They ultimately "ground-truthed" 303 geoglyphs through site visits, confirming their existence after visually examining AI-identified candidates.
Among the representations were a 72-foot-long orca wielding a knife and cutting off a human head, as well as motifs of plants, people, snakes, monkeys, cats, parrots, and llamas. The newly discovered geoglyphs average about 9 to 10 meters in size and are located near paths and roads, designed to be seen from the ground.
The Nazca civilization was a pre-Inca civilization in present-day Peru dating from 200 B.C. to 700 A.D. and created geoglyphs that reflect their spiritual and cultural landscape. Despite extensive studies, it remains unclear why the Nazca Lines were created.
The ancient geoglyphs have attracted theories ranging from the religious—they were tributes to powerful gods of the mountain and fertility—to the environmental—they were astronomical guides to predict the infrequent rains in the nearby Andes—or the fantastic—they were runways and parking lots for extraterrestrial ships.
Sakai said the geoglyphs were drawn near the pilgrimage routes to the temples, implying that they functioned as sacred spaces for community rituals. "I expect that more surprising facts will emerge," Sakai stated, The New York Times reports.
The Nazca civilization carved the designs into the earth by scraping back the pebbled, rust-colored surface to expose the yellow-gray subsoil, a technique that made the geoglyphs visible from the air. The first layer of soil in the Nazca desert consists of a mantle of small reddish stones, which, when lifted, reveal a second yellowish layer, used by the ancient Nazca civilization to create the geoglyphs.
The Nazca Lines were first discovered by outsiders in 1927 by a Peruvian scientist while hiking through the Nazca foothills. Over the next decade, commercial pilots flying over the Nazca region revealed the enormity of the artwork.
Apart from the geoglyphs, almost all that exists of the Nazca civilization are pieces of pottery and an ingenious irrigation network that still works.
Although the archaeological site is a restricted and protected area, the lines have been threatened by occasional acts of vandalism. In 2014, Greenpeace activists left footprints near the colossal hummingbird geoglyph during a protest aimed at delegates of the United Nations climate negotiations in Lima. In 2018, three geoglyphs were damaged when a truck driver reportedly avoided a toll by plowing a rig through the sand.
Of the original 1,309 candidates, Sakai estimates that there are at least another 500 undetected figures, The New York Times reports.
the New York Times, Sydsvenskan, and Dagens Nyheter reported on the findings.
This article was written in collaboration with generative AI company Alchemiq