An anthropologist finds a fossil that is 4 million years old. Its pelvis suggests it walked upright. Which species could the specimen belong to?

Australopithecus afarensis lived about 3.9 to 2.9 million years ago and walked upright, as indicated by its pelvis and other fossils. A specimen dated to 4 million years ago could therefore belong to this species. Australopithecus africanus and the Homo species listed are generally dated to later periods.

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