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How Crowdsourced Archaeology Could Help Solve the Mysteries of Peru

Archaeologists have studied the ancient city of Petra for more than 200 years. So I didn’t feel wildly hopeful about finding anything unknown when I did a satellite survey of the site in 2012. But then, there it was: a massive monumental platform. There are hundreds of thousands, if not millions, of unknown archaeological sites...

Archaeologists have studied the ancient city of Petra for more than 200 years. So I didn’t feel wildly hopeful about finding anything unknown when I did a satellite survey of the site in 2012. But then, there it was: a massive monumental platform. There are hundreds of thousands, if not millions, of unknown archaeological sites around the world, and new technology is helping us locate them. (See archaeologist Damian Evans’ recent LIDAR scan of Cambodia, which revealed multiple medieval cities in the jungle, each between 900 and 1,400 years old.)

I’m thrilled that Global Xplorer, the citizen science platform my team is developing with the 2016 TED Prize, will launch later this year. We’ll use the power of the crowd to locate unknown sites. But where to begin? There’s an entire world out there! I knew I wanted to start somewhere with a rich history. Somewhere where we could partner with key archaeologists to help explore what we find on the ground. Somewhere with breathtaking landscapes.

An aerial view of Nasca Lines resembling a monkey. Thousands of these geoglyphs adorn over 1,500 square miles of desert in Peru. Photograph: Bates Littlehales/National Geographic Creative.
An aerial view of Nasca Lines resembling a monkey. Thousands of these geoglyphs adorn over 1,500 square miles of desert in Peru. Photograph: Bates Littlehales/National Geographic Creative.

I’m excited to announce that Global Xplorer will launch in the country that’s the home to Machu Picchu, the Lord of Sipán, and the Nasca Lines: Peru. My team has started looking at high-resolution satellite imagery, and we’re already seeing potential sites, including what could be a new cemetery in the Nasca region. That’s four people looking for a few days. Imagine setting loose the world and having them look for months!

Below, four reasons why Peru is the perfect place to start this work.

1. The History Is Incredibly Rich.

Peru has large numbers of sites from many different cultures at many different time periods. Everyone knows the Inca, who flourished from 1438 to 1532 and worshipped the sun. They were incredible architects, who selected stones like puzzle pieces, then smoothed and pounded them to fit together without mortar. Their structures tend to be very rectilinear and regimented; they built sites along strict plans. Contrast that with the Chimú, who thrived from 1100 to 1470 and worshipped the moon. With them, you’re looking at earth-built structures, which can be harder to see in satellite imagery. Earthen structures burn, melt, and erode, so you’re not going to see a building per se; you’ll see the building’s effect on the landscape. And that’s really just the start of the diversity in Peru.

With Global Xplorer, we could see anything from a site like Machu Picchu, though probably not on that scale, to animal enclosures, to systems of irrigation canals, some of which date back thousands of years. There are possible ponds, roads, agricultural buildings — all of them need to be researched so that we can learn about the daily lives of the cultures that lived there.

We’re going to create a field guide that shows participants what different kinds of ancient sites look like in high-resolution satellite images. It’ll be a challenge to show every type of structure ever built in Peru, but humans are pretty standard in the way they build things; earlier structures tend to be round, and later structures tend to be rectilinear, for example. We just have to be very careful that we don’t claim we’ve found something that’s already known. That’s why, in every place we look, we’ll be collaborating with archaeologists who work in those areas.

2. Sites Are Often Well-Preserved.

Peru has something big going for it: The arid cold of the highlands and the dry heat of its coastal desert do an incredible job of preserving artifacts. Mummies found at sites in Peru sometimes seem life-like, with skin, hair, even tattoos. Sometimes, wood artifacts survive.

I’m especially interested in surveying the mountains. It’ll be a challenge, but there’s a lot to potentially find, as hilltop settlements and fortifications tend to be readily apparent. Throughout history, cultures in Peru retreated into the mountains for protection during times of unrest. They built homesteads, encampments, and cities. It’s possible that we’ll see man-made structures on exposed faces that others have missed because they’re isolated, or structures that are weathered and can only be seen from a top-down perspective. Structures might have fallen or burned, or have a layer of vegetation growth — but they’ll be close to the surface and not, say, covered by 20 to 30 feet of sand as we sometimes find in Egypt.

It still astounds archaeologists how the people in Peru’s mountains accommodated for the fact that the soil is not good for growing things. We’re likely to see raised areas of enriched soil and amazing agricultural terracing. People moved landscapes to live here.

3. We Can Fight Against Looting.

Global Xplorer will allow us to locate sites as well as looting. Looting pits are easy to spot in satellite imagery, and this data is very valuable. Looting has long been a problem in Peru; we have a good understanding of it through the 1990s, but not so much of the current scale and recent trends. Right now, we fear that looters are doing a better job of uncovering ancient sites than we are. In one region, my team has spotted entire towns that look like they’ve been looted.

In archaeology, context is everything. Without a piece’s context, whether it’s a tiny pot or a beautiful statue, we can’t understand its significance. Ancient sites are like time capsules. If objects are taken, we get the box with nothing inside. We lose the opportunity to learn about a culture’s religious beliefs and social structures.

The Peruvian government is already taking action against looting, and it’s interested in doing more. The government can’t monitor hundreds of sites at once, but Global Xplorer participants can. As we identify looting patterns, we will alert the government, local preservationists, and nearby communities, as warranted.

We’re working on making the platform available in Spanish, because we want people in Peru, especially school kids, to participate. My hope is that in Peru, we develop a good methodology for connecting our crowdsourced data with action on the ground. Ultimately, we want to develop a model that can be replicated globally.

4. We Can Help Prevent Urban Encroachment.

Looters aren’t the only ones threatening ancient sites. Sometimes people don’t know what’s there — or don’t see its value. In 2013, Peru’s Ministry of Culture filed a suit against a construction company whose workers had torn down a partially excavated pyramid at the site of El Paraíso, which could date back 5,000 years. According to reports, police stopped the workers from bulldozing three more structures.

In another case, the people who live near the ancient site of Farfán, once a city of the Chimú, used it as a garbage dump. When the government removed the trash, the land’s owner reportedly built a fence over the grounds.

Around the Nasca Lines, illegal mining is a big problem. In Lima, illegal shanty towns are going up, potentially damaging ancient treasures. If we don’t know what’s there, we can’t help protect it. By creating a map of sites and monitoring encroachment, Global Xplorer participants can make a difference.

Shaping Up Well

For the past four months, my team has been developing what the Global Xplorer platform will look and feel like. Our partners at TED, DigitalGlobe, and the National Geographic Society are working with key archaeologists, and I’m just back from Lima, where I was fortunate to meet with the Ministry of Culture and UNESCO. All is shaping up well.

In 1913, Hiram Bingham wrote in National Geographic magazine about his expedition to Machu Picchu. Peru is ingrained in the history of the National Geographic Society, and it feels ingrained in mine too. As a student, I worked at the Yale Peabody Museum of Natural History, where Bingham — a Yale professor — brought objects back from Machu Picchu. I remember being amazed during my junior year that a professor was studying actual bones from the site. The National Geographic Society played a key role in returning objects from the museum to Peru. With Global Xplorer, I hope that we can continue to highlight Peru’s amazing cultural heritage and inspire others to learn more.

Our timeline is to launch late in 2016. But this is just the beginning. A number of my colleagues have promised to share what users’ discoveries look like on the ground with YouTube videos and Periscope. We cannot predict what the world will find, but if the last few weeks in my lab are any indication, hold onto your alpacas.

Satellite archaeologist and National Geographic Fellow Sarah Parcak is the winner of the 2016 TED Prize. She’s using the U.S. $1 million prize to build Global Xplorer, a citizen science platform to allow people all over the world to join the search for ancient sites. The platform will launch late in 2016 and, as she builds it, Parcak is bringing Explorers Journal readers along for the journey. Sign up for updates.

Chase Childs and Cheyenne Haney of Global Xplorer contributed to this piece.

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Meet the Author

Sarah Parcak
Sarah Parcak is a space archaeologist, National Geographic Fellow, and the winner of the 2016 TED Prize. With this one-million-dollar prize, she’s building a citizen science platform that will allow anyone, anywhere, to join in the search for and protection of ancient sites by analyzing satellite images and detecting new sites as well as the tell-tale pits and marks of looting.