Cockroach locomotion study. Cockroach (Blaberus discoidalis) attached to a candle, runs over a freely rotating polystyrene ball, known as a kugel. A high speed camera tracks the leg movements for locomotion analysis. Cockroaches are the fastest land animals, able to run at 50 body lengths per second. Like other multi-legged animals, cockroach legs move together in groups (two legs from one side, one leg on the other). Each group forms a spring-loaded tripod. When one tripod touches the ground, the other alternates by lifting up, producing gait similar to bipedal animals. Photographed at the PolyPEDAL Lab, University of California, Berkeley, USA.