Abstract
The fossil remains of a juvenile Australopithecus africanus specimen from Sterkfontein Member 4 temporally confined on faunal grounds to 2.5–3.0 million years before the present (Myr B.P.) show pathological alterations of the periodontal alveolar process consistent with a case of prepubertal periodontitis. This diagnosis is based on macroscopic features of alveolar bone loss distribution, pattern of periodontal bone destruction, migration of the affected deciduous molars, and on stereomicroscopic and scanning electron microscopic evidence of alveolar bone destruction. Differential diagnoses and pathological exclusions are discussed in terms of localized patterns of periodontal bone destruction and presumptive survival rate. The reported case appears to be the first detailed description of a recognized disease in early hominid evolution.