By Dr. Becker
All animals have the ability to move in some form or fashion. Some fly, while others move through trees. Some run, some dig their way from place to place, and still others jump from point A to point B.
This latter group is referred to as having saltatorial locomotion ("saltation" = jumping), which means these creatures are equipped with large, muscular hind limbs and sometimes, reduced forelimbs.
Saltatorial animals include land mammals (e.g., kangaroos), sea mammals (e.g., whales), reptiles, amphibians, insects, and spiders.
It's important to understand the distinction between jumping and other motions in which the entire body is temporarily airborne, for example, running or galloping.
Animals that jump as their primary means of locomotion maintain a relatively long aerial phase, as well as a high angle when they launch their bodies upward.
Many land animals jump, hop, or leap to escape predators or catch prey, however, only a handful of creatures use jumping as their primary means of getting around.
Here are a few famous jumpers, starting with your favorite pest and mine, the flea.
Just a few years ago, scientists finally answered the burning question, "How do fleas harness the explosive energy needed to jump?" As it turns out, the little buggers push off with their toes instead of their knees, as was originally thought.
According to the video below, "fleas transmit their stored energy through leg segments that act as levers, pushing down on the toe to launch the tiny animals up to 13 inches, or 200 times their own body length."
No, the froghopper isn't a cross between a frog and a grasshopper! But the name isn't this little creature's only quirk. Froghoppers are best known for their plant-sucking nymphs, which encase themselves in froth in springtime.
Froghopper nymph encased in froth Froghopper
According to National Geographic, the froghopper, "a sap-sucking bug that coats plants with wads of foamy spit" is the insect world's greatest leaper:
"It has more jumping prowess than fleas, out hops the springiest grasshoppers, and clears the high bar more quickly than bush crickets."1
The average length of an adult froghopper is just .12 inches, but it can launch itself up to 2 feet in the air. That's the equivalent of you or me jumping over 600 feet!
The back legs of these little jumpers operate like a catapult. The muscles that power his back legs function as rubber bands. When the grasshopper readies for a jump, he contracts the large flexor muscles in his back legs slowly, while bending the legs at the knee joint.
Per About.com, "A special piece of cuticle within the knee acts as a spring, storing up all that potential energy." When he's ready to jump, he relaxes the leg muscles, allowing the spring to release its energy and catapulting his body into the air.2
Once airborne, the grasshopper can choose to fly to even greater heights. If humans could jump in a similar fashion, we could easily cover the length of a football field!
You would think frogs would have monster back leg muscles to power all the jumping they do, but the fact is, their leg muscles aren't as major as they would need to be to get the job done on their own. We know this because researchers have actually filmed frogs jumping at 500 frames per second, using x-ray cameras that allow them to see inside those back legs as the jump is executed.
The secret of the frog's leaping prowess is actually in the tendons of the legs. When a frog prepares to jump, the tendons stretch out to their limits, and the muscles shorten, transferring energy to the tendons. The tendons recoil like springs, and the frog blasts off!