 However, such divergence in chewing adaptations may instead have been a response to fallback food availability.In leaner times, robust and gracile australopithecines may have turned to different low-quality foods (fibrous plants for the former, and hard food for the latter), but in more bountiful times, they had more variable and overlapping diets.A study in 2018 found non-carious cervical lesions, caused by acid erosion, on the teeth of "A. africanus", probably caused by consumption of acidic fruit.