Archaeologist and National Geographic Explorer Thomas Garrison, who viewed the data around the same time, was stunned by what he saw. “I think we were feeling something similar to what astronomers felt the first time they looked through the Hubble Telescope and saw all those empty spaces suddenly teeming with stars and galaxies,” he says. “Here was this vast jungle that everyone thought was nearly empty. And then, when we peeled off the trees, there were human signatures everywhere.”