Final answer:
Lucy, an Australopithecus afarensis, demonstrated bipedal locomotion with a modern striding gait indicated by the Laetoli footprints. She had anatomical features such as a broader pelvis and arched feet optimized for upright walking.
Step-by-step explanation:
According to the film Walking with Cavemen, the pattern of locomotion of Lucy, a member of the species Australopithecus afarensis, is best described as bipedal. This is supported by the discovery of the Laetoli footprints, which indicate a modern striding gait used by this early hominin. Lucy's species paved the way for evolutionary changes, and this form of bipedalism, characterized by one leg being the stance leg while the other is the step leg, shows many anatomical changes to enable balance and movement on two feet.
Lucy exhibited anatomical features necessary for upright walking, such as a broader pelvis and arched feet, which are similar to those of modern humans, highlighting the efficiency of her bipedal locomotion. Such adaptations are significant in the discussion of human evolution and the development of bipedalism among early hominins.