Teeth from a 1.8-million-year-old human fossil show signs of disease and are extremely worn — possibly from eating hard and fibrous foods.

In 2000, researchers uncovered a jaw bone (pictured) at a site in Dmanisi, Georgia, which has produced the oldest human fossils outside Africa. Laura Martín-Francés at the National Research Centre on Human Evolution in Burgos, Spain, and her team examined the fossil, dubbed D2600, including its teeth. Most of the teeth had no protective enamel left, and the roots and interior showed signs of infection.

Credit: E. LACASA-MARQUINA/L. MARTÍN-FRANCÉS

The wear patterns — which are unlike those of other human specimens of a similar age — could have been caused by a diet of abrasive and fibrous plants and fruits, similar to that of apes, the researchers say.

Comptes Rendus Palevol http://doi.org/q5t (2014)