Answered by Quinn Shurtliff, Wildlife Biologist, INL ESER Program
The difference between a rabbit and a jackrabbit boils down to this simple fact: the jackrabbit is not a rabbit at all, it’s a hare. Jackrabbits are native to North and Central America and comprise six of about 30 hare species worldwide. Apparently, the long ears of the jackrabbit reminded some people of donkeys, as they were initially referred to as jackass rabbits.
Hares are typically larger than rabbits, with longer ears and legs, the latter allowing them to outrun enemies in the deserts and prairies they call home. In fact, some hares can run up to 40 mph! Rabbits, with their shorter legs and preference for brushy habitats, prefer to dive into cover or a nearby burrow to avoid becoming a tasty meal. Incidentally, another difference between rabbits and hares is that some rabbit species occupy burrows, but hares do not. We can conclude, then, that Bugs Bunny is truly a “wabbit” because he frequently has been known to tunnel underground all the way from Albuquerque.
One of the most interesting differences between hares and rabbits is the condition of the babies at birth. Newborn hares, called leverets, are born fully furred, eyes open, and ready to hop around within a few minutes of being born (remember, hares are haired at birth). Baby rabbits, known as kits or kittens, are born naked and with eyes sealed. They are completely helpless for the first several days.
Eastern Idaho is home to three hares: the black-tailed jackrabbit, the white-tailed jackrabbit, and the snowshoe hare. The white-tailed jackrabbit and the snowshoe hare grow white hair during their autumn molt, a trait that is unique to hares. Our local rabbits include the cottontail and pygmy rabbit, the latter holding the distinction of being the smallest rabbit in the world (and perhaps the cutest).
Why Do Rabbits and Hares Hop?
Rabbits and hares belong to the family Lepoidae. Scientists call members of this family Leporids. Leporids were made to hop. Their back legs are long and strong. They can leap forward great distances with a single push from their back legs. They usually land on their front legs, which help them balance while their back legs spring forward into position to push off for another leap forward.
Leporids have such strong legs that they can move as quickly as 50 miles per hour in short bursts.
Their strength is also good for leaping into the air and forward over the ground. Leporids can easily leap almost four feet into the air and nearly 10 feet forward in a single bound. This is an important ability for Leporids, since many other animals hunt them as prey.
When the Leporid hits the ground, it stretches the elastic tendons and ligaments that run throughout its body, storing energy much the way a pogo stick does in its spring. As the animal takes off, the energy is released.
Most other animals, such as humans, store little energy as they move. Each time they take a step almost all energy is lost and their muscles must produce new energy.
Elastic potential energy
Elastic potential energy is energy stored as a result of applying a force to change the shape of an elastic object. The energy is stored until the force is removed and the object springs back to its original shape, doing work in the process. A stretched rubber band or a bouncing ball are examples of elastic energy.
You can produce your own elastic energy by stretching a muscle! We’re going to do jumping jacks.
- Stand upright with your legs together, arms at your sides. Bend your knees slightly.
- Hold this position. What type of energy do you have? What are you getting ready to do? (Answer: Storing potential energy that is waiting to be converted into kinetic energy when you jump into the air.)
- Complete the jumping jack by jumping into the air. As you jump, spread your legs to be about shoulder-width apart. Stretch your arms out and over your head. As you move, you are creating kinetic (moving) energy.
- Get ready to jump back to your starting position. Are you storing potential energy that will be used when you move again?
- At what points in your jumping jack did you have potential energy? At what points in your jumping jack did you have kinetic energy? How does your potential and kinetic energy change when you make your jumping jack faster? Slower?