How AI spotted hundreds of new giant Nazca lines

HostMost of us have seen photos of those huge shapes cut into the dirt in Peru. They're so big you can only see them from a plane, and for a long time, we thought we had found all the main ones. But it turns out there were hundreds of smaller drawings hiding in plain sight, and we needed a new way of looking to find them. How did a computer program manage to spot what people missed for decades?

GuestIt's pretty wild because people have been walking over these spots for a long time. These new drawings were found in the Nazca desert, and the reason they stayed hidden is that they're not like the huge ones everyone knows. The big ones, like the spider or the monkey, are made of long lines. But these hundreds of new ones are what experts call relief drawings. They're made by clearing away dark stones to show the lighter sand underneath, and they're usually much smaller. They might only be thirty feet across, while the big ones are hundreds of feet long. Because they're small and the lines are thin, they sort of fade into the background. A person looking at a photo might just see a pile of rocks or a blur. But a team of experts used an AI model to scan through huge maps made from drone photos. In just six months of work on the ground, this tool helped them find three hundred and three new shapes. To put that in perspective, it took humans nearly a century to find about four hundred and thirty of them before this.

HostSo, is the computer basically just looking for anything that looks like a doodle? That feels like it would give you a lot of false hits.

GuestYou're right, and that was the hard part. You can't just tell a computer to look for a llama. These drawings are two thousand years old. They're worn down, covered in dust, and some are nearly gone. Usually, to train an AI, you need thousands of examples so the machine knows what to look for. But we only had a few hundred known drawings to show it. So the team had to build a system that could learn from a very small number of pictures. They showed the program a few examples of what a drawing looks like versus what a random rock pile looks like. The AI then scanned the whole desert and pointed out places that looked likely. It didn't say, hey, here is a bird. It just said, this spot looks a bit weird, you should go check it out. Then the humans had to go out into the heat, walk to those exact spots, and see if there was actually anything there.

HostBut if a person still has to walk out there and check, did the AI really do the heavy lifting? It sounds like it just gave someone a very long to-do list.

GuestWell, it's a to-do list that would be impossible without the help. The desert is huge, and most of it's empty. If you just went out there and started walking, you would find nothing for weeks. The AI cut the search area down by a massive amount. Think of it like a metal detector. It doesn't dig the hole for you, but it tells you exactly where to put your shovel. The model was able to see patterns in the rocks that our eyes just skip over. When the team went to the spots the AI flagged, they found that over eighty percent of the time, there was actually a drawing there. That's a huge win. And what they found was totally different from the big lines. Most of the new ones are of people, or heads that have been cut off, or things like cats and llamas.

HostWait, why would they draw heads that were cut off? That feels a bit different from a giant bird or a monkey.

GuestIt really changes how we think about the people who lived there. The big lines were likely for the gods to see from above, maybe for ceremonies about rain. But these new, smaller ones are mostly found along old footpaths. They're not meant for the sky. They're meant for people walking by. It's almost like a signpost or a way of telling a story to travelers. Seeing these heads and human figures suggests they were marking their territory or showing their beliefs to anyone passing through. It makes the desert feel less like a giant temple and more like a place where people were actually living and moving around.

HostIt still feels a bit like we're losing the mystery of it all by letting a machine do the hunting. I mean, part of the fun of these old sites is the idea of a person stumbling upon something lost.

GuestI think it's actually the opposite. The machine is showing us that there's so much more to find than we ever imagined. We used to think we were looking at the whole picture, but the AI showed us we were only looking at the biggest, loudest parts. It's like we were only reading the headlines of a book and the AI is helping us read the fine print. There are still thousands of acres to scan, and the more we find, the more we realize how busy this desert used to be. The AI isn't taking away the hunt, it's just giving us better eyes so we can see what was right under our feet the whole time.

GuestThe sheer number of these smaller figures shows us that the desert was a vibrant map of stories rather than just a blank space.

HostThat dusty ground has been holding onto those secrets for thousands of years, and now we finally have the right tools to read them.