Tuberculosis has a long history in humans. While Egyptian mummies a few thousand years old show evidence of the disease, a new fossil find traces the pathogen’s presence back 500,000 years to an ancestral species in the Homo genus. Workers cutting deposits of travertine, a white rock used for building construction, in the Denizli province of western Turkey chanced upon a skull embedded in a block they were slicing into tiles. The top of the skull—which was sliced off from the remainder, which was lost—has small pits in the interior. These scars are telltale signs of a type of tuberculosis that infects the brain. The discovery illustrates how long this pathogen has persisted and coevolved with humans over evolutionary time.