Locomotion

Locomotion is the self-propelled movement of an organism from one location to another, achieved through the coordinated action of muscles, skeletons, and sometimes special locomotor organs. It enables resource acquisition, predator avoidance, dispersal, and mating, and its form is closely tied to an organism’s anatomy and environment.

Terrestrial locomotion includes walking, running, hopping, climbing, and crawling, typically powered by limbs or body movements that generate propulsion while negotiating gravity and terrain. Aquatic locomotion relies on fins, tails, or whole-body undulation to push against water, producing thrust and maneuverability. Aerial locomotion uses wings or gliding surfaces to generate lift and forward motion. Some organisms employ alternative strategies such as jet propulsion or rolling to move in fluid environments.

Biomechanics studies how propulsion, resistance, lift, and energy expenditure interact to produce movement. Gaits describe patterned limb coordination, such as walking or running in land animals, while various forms of swimming include undulatory and oscillatory modes in aquatic species. Locomotion depends on the center of mass, body stiffness, and available muscle power, with trade-offs between speed, stability, and energetic efficiency. Microorganisms use cilia, flagella, or jet-like mechanisms to move.

Locomotion has evolved repeatedly, yielding a remarkable diversity of forms adapted to air, water, and land. The study of movement informs disciplines from biomechanics and functional morphology to robotics and rehabilitation, supporting advances in prosthetics, legged and flapping-flyer designs, and movement therapies.

Researchers assess performance using metrics such as speed, endurance, stride length, and metabolic cost, comparing species and contexts to understand ecological relationships and evolutionary constraints. Locomotion shapes behavior, habitat use, and interaction with the environment.