The food an organism ingests can also produce subtle changes in the chemistry of body tissues (you actually are what you eat), including the dentin and enamel that make up the crown of a tooth.
The change in ecology associated with H. erectus coincides with a corresponding change in the dentition and jaws of this species. Relative to earlier australopiths and contemporary robust australopiths ( Paranthropus), the size of the post-canine dentition (premolars and molars) and the molarization of the premolars are dramatically reduced in H. erectus. The corpus of the mandible (i.e., the toothless part that connects to the cranium) also displays increased gracility (i.e., slenderness), with a characteristic reduction in the relative breadth of the structure and supportive masticatory structures. Toothwear analyses suggest that across their range, H. erectus engaged in a diverse and broad diet (Ungar et al. 2006). The food an organism ingests can also produce subtle changes in the chemistry of body tissues (you actually are what you eat), including the dentin and enamel that make up the crown of a tooth. Using this information, investigations of the stable isotope chemistry of H. erectus teeth also support the idea of a flexible and diverse diet (Ungar & Sponheimer 2011). Whatever the flora and fauna H. erectus ate at the varied geographic localities where H. erectus fossils are found, their tooth and jaw anatomy reveal that their diet did not require the same robust masticatory adaptations seen in earlier hominins.