the teeth go to christina warinner's lab at the university of oklahoma.t's a highly sterile workplace, built to protect ancient samples from the modern dna that surrounds us. warinner: there is dna everywhere. every time you cough or sneeze, you're putting dna into the air. so if we want to be able to recover this very ancient and degraded material, we have to get rid of all of that extraneous dna as much as possible. so we conduct this work in special laboratories that have highly filtered air. we have ultraviolet radiation built into the ceiling to sterilize the room in between uses, and we wear these tyvek suits, which help keep our dna in. most people, when they see them, they're used to seeing them in context of people in epidemics trying to protect themselves from disease. we wear them for the reverse reason. we're trying to protect our samples from our dna. we clean the teeth with bleach to remove and destroy any dna on the surface. in a way, it's almost like getting a very belated dental cleaning. we use an abrasive tool to remove the outer layer,