Final answer:
Early hominin fossils are recognized by adaptations for bipedalism, including specific features of the pelvis, legs, and feet, as well as changes in dental and cranial structures indicative of dietary and behavioral shifts characteristic of early hominins.
Step-by-step explanation:
Two characteristics commonly used to recognize early hominin fossils are bipedalism and dental structures. Key adaptations that define hominins include walking on two feet, as evidenced by pelvis and leg bones conducive to bipedal locomotion, and features within the feet such as arches and particular ankle structures. Moreover, changes in skull and dental patterns, like smaller jaws, reduction in prognathism, and humanlike teeth arrangements play a significant role in identifying hominins. The Laetoli footprints discovered by Mary Leakey are a remarkable example, providing crucial evidence of bipedalism. Fossils of species like Homo habilis illustrate the transition toward a larger brain size, the use of tools, and specific physical traits that distinguish early human ancestors from other primates.