Final answer:
The way an animal stands can be determined based on the angling of its femur, the alignment of its foot, and the curvature of its spine. These adaptations facilitate bipedal locomotion and help balance the weight of the upper body. The valgus angle, arch in the foot, and realignment of the big toe all contribute to the way an animal stands.
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. This adaptation, known as the valgus angle, makes bipedal locomotion (walking upright) more comfortable and more efficient. Bipedal hominins have also evolved spinal curves that make it possible for the hips to balance the weight of the upper body. 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 is also instrumental in transmitting weight during the step phase of bipedal locomotion.