Final answer:
Early human ancestors' dentition demonstrates a mix of human and ape-like features, such as small jaws, bipedalism and large molars similar to humans, as well as a sagittal keel and different brain size more akin to apes.
Step-by-step explanation:
The dentition of early human ancestors, like Australopithecus and early Homo species, shares similarities with both modern humans and apes. Characteristics such as small jaws and teeth, the presence of a third molar that is larger than other molars, and a bipedal posture align with human features. Conversely, aspects like a sagittal keel and differences in brain size suggest a closer resemblance to great apes. Moreover, the robust Australopithecines had large temporalis jaw muscles indicated by a sagittal crest which contrasts with the gracile Australopithecines that had smaller teeth and jaws similar to humans. Additionally, elements such as humanlike feet with arches and ankles, and the adjustment of teeth to our diets further connect our dental and skeletal structures to our ancestral lineage.