Final answer:
Bipedalism emerged around 6-7 million years ago and is characterized by walking on two legs. Early hominins like Homo erectus had adaptations for bipedal locomotion. Anatomical changes in the femur, spine, feet, and toes have facilitated successful bipedalism.
Step-by-step explanation:
Bipedalism, or walking on two legs, emerged around 6-7 million years ago. Early hominin species like Homo erectus had adaptations for bipedal locomotion such as a broader pelvis, longer legs, and arched feet. Fossil evidence, like the footprints found at Laetoli, provides important clues about the evolution of bipedalism. One of the key anatomical changes for successful bipedalism is the angling of the femur inward, which positions the knees and feet under the center of the pelvis. Bipedal hominins have also evolved spinal curves, arches in the feet, and the realignment of the big toe for weight transmission.