AI discovers hundreds of ancient Nazca paintings in the Peruvian desert

With the help of artificial intelligence, hundreds of ancient drawings depicting decapitated human heads and domesticated llamas have been discovered in the Peruvian desert, and archaeologists have previously linked the works to the Nazca people, who began carving such drawings, called geoglyphs, into the ground about 2,000 years ago.

These lines are smaller and older than the Nazca Lines and other lines found so far. They contain large geometric shapes spanning several kilometers, as well as wild animals that average about 300 feet. The newly discovered lines generally depict humanoids and domestic animals about 30 feet long. Some depict decapitated heads and killer whales holding blades, suggesting they were sacrificed.

“Nazca pottery depicts scenes of killer whales with knives decapitating humans,” says Masato Sakai of Yamagata University in Japan, “which positions killer whales as creatures that perform human sacrifice.”

Sakai and his colleagues found the tiny geoglyphs by training an AI model to look for them in aerial photographs. The high-resolution photos cover an area roughly 10 times the size of Manhattan, including the Nazca Plateau and its surrounding areas, home to the Nazca Lines, a UNESCO World Heritage Site. The AI ​​created a grid map that classified the probability that each grid square contained a geoglyph.

The researchers still spent more than 2,600 hours manually inspecting the most likely photos and conducting fieldwork in the field, but the AI ​​helped them speed up the screening process by 50 times by “eliminating 98% of the unlikely aerial photos from consideration and giving the remaining 2% a chance,” says co-author Markus Freitag of IBM Research in New York.

The researchers followed the AI’s suggestions and discovered a total of 303 figurative geoglyphs during field surveys in 2022 and 2023. Of these figures, 178 geoglyphs were identified individually by the AI. The other 66 were not directly identified, but the researchers found them within groups of geoglyphs highlighted by the AI.

“AI-based analysis of remote-sensing data is a major step forward, as a complete map of the Nasca lines is not yet available,” says Carsten Lambers of Leiden University in the Netherlands, but he cautioned that “even this powerful new technology is more likely to find the more visible lines—the ones that are easy to spot—than the more difficult lines that likely remain undiscovered.”

According to Sakai, there are nearly 1,000 potential sites identified by AI that are waiting to be investigated in future field surveys. These small geoglyphs typically appear on hills near winding paths and likely featured in “individual or small group ritual activities.” In contrast, the large linear geoglyphs were likely centers of community-wide rituals, Sakai said.

David Beresford-Jones of the University of Cambridge says the AI ​​screening process also offers hope for finding lines beyond the Nazca Lines World Heritage Site in the wider area. Speed ​​is of the essence, he says, because many lines are “on the brink of disappearance due to agricultural expansion, urban development and wind power.”