Final answer:
Bipedalism is the form of locomotion using two rear limbs or legs. It is a characteristic feature of humans and some other primates.
Step-by-step explanation:
The form of locomotion using two rear limbs or legs is called bipedalism. It is the ability to walk on two legs. Bipedal locomotion is a characteristic feature of humans and some other primates.
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. 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.
Keywords: locomotion, legs, bipedalism