Final answer:
The Laetoli footprints reveal that Australopithecus afarensis walked upright with a modern striding gait, confirming bipedalism in this early hominin species.
Step-by-step explanation:
The Laetoli footprints are a significant discovery that provides evidence of bipedalism in the early hominin Australopithecus afarensis. Mary Leakey's discovery of a 75-foot trail of footprints preserved in wet volcanic ash dated 3.5 million years ago in East Africa at the site of Laetoli revealed that Australopithecus afarensis walked upright with a modern striding gait. Despite some differences in morphology, such as longer arms and curved finger and toe bones suggesting tree-dwelling behavior, the shape of the pelvis and the anterior position of the foramen magnum distinctly indicate that A. afarensis was adapted for bipedal locomotion. This bipedality is a pivotal moment in human evolution, as it is one of the key features that distinguish early hominins like A. afarensis from their great ape ancestors and set the path toward the evolution of modern humans.