Limbs are drastically modified to different ends in various groups of mammals. Here, we are concerned primarily with modifications that affect how an animal runs. Running Fast Several terms describe how and where an animal moves. Hoppers are termed saltatorial . If they use their hindlimbs only and in a fast succession of hops, they are said to be ricochetal .
Fossorial forms are diggers, usually living in burrows.
Here, we focus on the adaptations of cursors. A full cycle of motion of a running or walking mammal is called a stride . An animal's speed is the product of its stride length times rate. There are two ways of increasing the speed of running, increasing stride length and increasing stride rate. Stride length 1.