Large ancient drawings etched into the desert in southern Peru have fascinated researchers for years. Now they've got 143 more of the figures—known as Nazca lines—to ponder. Researchers from Japan's Yamagata University announced the discovery of the geoglyphs in a news release. As with the previously discovered figures, some are so large—more than 300 feet long—they can only be seen through aerial views, reports the New York Times. They depict all kinds of animals, from snakes to alpacas, as well as human forms. One in the latter category is especially notable: It's the first one ever discovered with the help of artificial intelligence, per the Verge. Researchers used IBM software to hunt for telltale shapes, and they settled on one candidate in particular to investigate. It turned out to be a human figure, about 16 feet tall, holding a club or cane.
"It is in an area that we often investigated, but we did not know the geoglyph existed," says the university's Makato Sakai. "It’s a large achievement." These drawings and previously discovered ones date from 200BC to 500AD and are in a stretch of desert measuring about 200 square miles, notes the Smithsonian. How they are made isn't too mysterious: Workers scraped away dark topsoil and rocks to reveal white sand below. But the "why" remains mostly a puzzle. Leading theories are that the smaller ones were travel markers and the larger ones were part of astronomical rituals, according to the Times. Researchers hope continued study—including with AI—will shed more light on all this, as well raise awareness that the entire region needs to be better protected. (A truck driver once did serious damage to some of the drawings.)