The tooth fairy may be good at doling out cash for lost teeth when we’re kids, but it disappears when we lose a bicuspid as adults. Not so with American alligators, whose teeth can regenerate up to 50 times. USC researchers have uncovered the cellular and molecular mechanisms behind tooth renewal in alligators. The scientists found that when an alligator loses a tooth, latent stem cells are activated, triggering tooth development. The researchers hope this discovery could lead to tooth regeneration in adult humans, whose pearly whites are naturally replaced only once. [This article originally appeared in print as "Alligators and the End of Dentures?"]
