Final answer:
The most important parameter in locomotion involves an organism's anatomical adaptations that facilitate movement, such as limb structure and joint flexibility. Examples include the long arms of brachiators for swinging, the leg length of leapers for jumping, and the particular structure of the bipedal stance leg and step leg.
Step-by-step explanation:
The most important parameter in most forms of locomotion is how an organism's physical structure allows it to move through its environment effectively. For instance, brachiators, like certain primates, possess long arms suitable for swinging from branch to branch, while leapers have long legs for jumping. Bipedal animals, such as humans, have their own specific requirements and anatomical adaptations to facilitate movement on two legs.
Important to bipedal locomotion is the existence of certain anatomical changes, such as the femur's valgus angle, which helps position the knees and feet beneath the pelvis. Other adaptations include spinal curves to balance the weight of the upper body, the development of an arch in the foot for weight distribution, and the realignment of the big toe so that it is parallel to the other toes—all critical for efficient walking and running.
Mammals are known for their versatile and mobile limbs, with creatures like the cheetah reaching remarkable speeds due to their body structure. In kangaroos, the bending of the hind legs provides shock absorption during hopping. Even the transition of vertebrates onto land from the sea involved significant shifts in body design tailored for terrestrial movement, away from the buoyant support of water to the resistance of solid ground.