Two of Australia’s indigenous creatures, kangaroos and emus, have something in common—they seldom move backward. Kangaroos, because of the shape of their body and the length of their strong tail, can bounce along with forward movement, but they cannot shift easily into reverse. Emus can run fast on their strong legs, but the joints in their knees seem to make backward movement difficult. Both animals appear on Australia’s coat of arms as a symbol that the nation is to be ever moving forward and making progress.