In 1951 two men arrived in Dom Pedrito, a town in southern Brazil, to carry out geological mapping of the pampa, or low grassland. There they found a rocky hill brimming with the remnants of a wetland ecosystem that existed some 260 million years ago.
During the Permian period, when most of Earth’s landmass was still bound up in the supercontinent Pangea, this part of what is now Brazil was covered in vascular plants like horsetails and ferns, and a nearby body of water contained various aquatic creatures. This ecosystem existed shortly before a mass extinction dealt a major blow to life on Earth and set the stage for the rise of the dinosaurs, making the fossil site a significant paleontological find.
But the researchers didn’t leave a description of the exact location of the extraordinary site they had unearthed, a three-acre patch among about 450 acres of land. So as time passed, and the dirt roads they had followed decades ago were replaced by paved highways that traced different routes, the site was lost to science.