Question

You are an archaeologist digging at a site in east africa. in a layer of earth dated to 4.5 million years, you find fossils of a hominin species with low sexual dimorphism in canine size relative to apes, a pelvis that is intermediate in shape between humans and apes, an anterior foramen magnum, and a grasping big toe. which of the following species is it most likely to be?

A. Ardipithecus ramidus
B. Australopithecus afarensis
C. Homo habilis
D. Paranthropus boisei
E. Homo erectus

Answer 1

The fossil characteristics described by the student are consistent with Ardipithecus ramidus, a species that exhibited a blend of bipedalism and arboreal lifestyle, and possesses anatomical features aligning with the described fossils.

Step-by-step explanation:

The fossils you describe are most likely to be Ardipithecus ramidus. This species is known for its low sexual dimorphism in canine size relative to apes, a pelvis that is intermediate in shape between humans and apes, an anterior placement of the foramen magnum, and a grasping big toe. These characteristics are consistent with the fossils of Ardipithecus ramidus, which were found in Ethiopia and dated to approximately 4.4 million years ago. In particular,

Ardipithecus ramidus shows evidence of both bipedalism on the ground and an arboreal lifestyle, suggested by the opposable big toe, which is not typical of later hominin species such as Australopithecus afarensis or Homo habilis. Moreover, the context of a heavily forested environment in which Ardipithecus ramidus fossils were found aligns with the characteristics of the fossils you discovered.