Final answer:
The angling of the femur, the evolution of the foot arch, and spinal curves are important changes that contribute to bipedal locomotion.
Step-by-step explanation:
One of the most important anatomical changes that facilitate successful bipedalism is the angling of the femur (upper leg bone) inward at what is referred to as a valgus angle, which positions the knees and feet under the center of the pelvis. Another important change is the evolution of the arch in the foot as well as the realignment of the big toe so that it is parallel to the other toes to help transmit weight during bipedal locomotion. The spinal curves that make it possible for the hips to balance the weight of the upper body also contribute to bipedal locomotion.