About 12,000 years ago, early inhabitants of Mexico’s Yucatan coast went deep into a dark, dangerous cave system, archaeologists reported a few years ago, based on their find of human remains. No evidence of habitation was found in the Quintana Roo cave system, however, which begged the question of what the ancient people were doing there.
Now we know. The paleo-spelunkers were mining for ocher, according to an international team including scientists, officials from Mexico’s Instituto Nacional de Antropología e Historia, and divers from the nonprofit group El Centro Investigador del Sistema Acuífero de Quintana Roo. They discovered the antiquities while exploring the partially submerged cave system for entirely different reasons, the journal Science Advances reports.
“Most evidence of ancient mining on the surface has been altered through natural and human processes, obscuring the record. These underwater caves are a time capsule,” says co-author Eduard Reinhardt, and expert diver and professor at the School of Geography and Earth Sciences at McMaster University in Ontario.