Kangaroos cannot walk backwards. Their hopping movement is called saltation. During saltation, kangaroos push off with both large feet at the same time, and they use their tails for balance. The combination of their muscular legs, big feet and tails may help kangaroos move forward effectively, but these appendages also prevent them from going in reverse.
Like kangaroos, emus are from Australia. They are flightless birds similar in looks and characteristics to ostriches, though they average about 10 inches shorter in height. Unlike ostriches, emus cannot walk backwards; however, it’s not known why. Emus are known for their fast sprinting and long distance running. They’re the only bird species that has calf muscles.