In a remarkable fusion of ancient mystery and modern technology, archaeologists have uncovered 303 new giant geoglyphs in Peru's Nazca Desert, thanks to the boost of artificial intelligence (AI). This discovery, detailed in a study published in PNAS, nearly doubles the known count of Nazca geoglyphs—mysterious ground artworks crafted by moving stones or gravel approximately 2,000 years ago.

Led by Masato Sakai, a professor of archaeology at Japan's Yamagata University, the team trained an object detection AI model on high-resolution imagery of the 430 previously mapped Nazca symbols. This collaboration, which included researchers from IBM’s Thomas J. Watson Research Center in New York, focused on the smaller, more figurative geoglyphs, which are typically around 30 feet in length and more challenging to spot than the larger line-type geoglyphs that measure up to 300 feet.

Despite the AI model's impressive performance, it was far from infallible, suggesting over 47,000 potential sites across the 243 square miles of desert. However, for every 36 AI suggestions, one promising candidate was identified, a significant acceleration of the discovery process. The team then conducted a six-month field survey, verifying the AI's predictions on the ground and uncovering the new geoglyphs, which include depictions of birds, plants, spiders, and human-like figures, as well as a unique orca wielding a knife.

The use of AI in this project is hailed as a "game changer," streamlining the laborious process of narrowing down potential sites and allowing researchers to concentrate on targeted fieldwork. The technology not only expedited the discovery rate but also offered insights into the purpose of these enigmatic symbols. The main hypothesis suggests that they formed a sacred space, possibly used for pilgrimage. Other theories propose roles in calendars, astronomy, irrigation, or as aids for movement and communication.

Sakai's analysis revealed that the larger geoglyphs, visible from above, typically depict wildlife, while the smaller ones include human figures or scenes such as sacrifice and domesticated llamas. The discovery also highlighted a network of ancient paths, indicating that the smaller geoglyphs were likely viewed in small groups, while the larger ones were part of communal ceremonies or public architecture.

The research team was unable to survey 968 promising candidates during the fieldwork season, suggesting that many more geoglyphs await discovery. Amina Jambajantsan, a researcher at the Max Planck Institute of Geoanthropology in Germany, who was not involved in the study, praised the use of AI but emphasized the不可或缺的human element in archaeological research.

As the mystery of the Nazca geoglyphs deepens, Sakai and his team continue to work on deciphering their precise meaning and purpose, with future publications anticipated to shed further light on these ancient wonders.