During the two centuries Western archaeologists have excavated and investigated ancient Maya sites, comparatively little time has been spent understanding the structures that kept cities functioning for centuries. "Unfortunately, there's this almost 200 year legacy of people focused on burial chambers and temples and hieroglyphics," says Kenneth Tankersley, an archaeological geologist at the University of Cincinnati. "No one had been asking the question, 'well, how did these people survive in this biologically stressful environment?'"