The hind legs of grasshoppers and locusts amplify jumping power via energy stored in muscle attachment sites.
Introduction
Imagine leaping over tall buildings in a single bound––for grasshoppers, that’s not comic-book heroics but sheer survival. These insects are real-life super-leapers, rocketing up to 20 times their body length in a single jump.
Grasshoppers live in habitats from sunlit meadows to dry scrublands, always ready to launch themselves away from danger. Their powerful leaps come not just from strong muscles, but from a clever system that stores and releases energy like a natural catapult––a stark contrast to the way mammals (including humans) leap.
The Strategy
Where the Muscles Are
Look at a grasshopper from the side, and you’ll notice its extra-long back legs folded along its body like a pair of jackknives. Each leg has two main parts:
-
Femur (upper leg): the thick, sturdy “thigh” segment.
-
Tibia (lower leg): the slender “shin” segment.
The key jumping muscles are tucked inside the femur:
-
Extensor tibiae muscle runs along the top and inside the femur. It straightens the knee (extends the tibia outward).
-
Flexor tibiae muscle lies more on the bottom side of the femur. It bends the knee, pulling the tibia back in.
During jumping, both muscles briefly contract at the same time (co-contraction), building up tension without movement. The flexor holds the tibia bent, while the extensor tries to straighten it.
On the very first page of the very first comic to feature Superman, creators Jerry Siegel and Joe Shuster turned to facts about ants and grasshoppers and readers' connection to nature to give this new hero’s fantastic abilities an air of plausibility. Image from @biomimicryinstitute on Instagram
The Semilunar Process: Shape and Mechanics
The “semilunar process” (from the Latin for “half-moon”) is a stiff, crescent-shaped piece of exoskeleton found on each side of the knee joint (where the femur meets the tibia). Picture two little curved plates shaped like parentheses: ( ).
-
Location: They nestle just above the joint hinge, integrated into the back wall of the femur.
-
Material: Made of highly elastic cuticle, a lightweight composite of chitin fibers, arranged to be stiff yet flexible.
-
Function: As the extensor muscle tightens, it compresses these curved plates inward like squeezing a bent spring. The shape lets the semilunar processes deform elastically, storing potential energy — rather like bending a diving board.
Once released, these “springs” snap back to their original shape in milliseconds, driving the tibia to extend violently outward. This produces the explosive power of the jump.
Why Muscles Don’t Just Do It Alone
Muscle alone can’t solve the speed-versus-strength problem:
-
Mammalian muscles produce high force but only slowly.
-
For rapid, high-power movements, muscle power isn’t enough without extra help.
The grasshopper’s catapult mechanism lets it load energy slowly into stiff structures and release it rapidly, achieving power outputs impossible for muscles alone.
How the Flexor Releases So Fast
The sudden “trigger” comes from the flexor tibiae muscle. While both flexor and extensor muscles are co-contracted, the flexor locks the tibia in a flexed position. A sudden neural signal causes the flexor to relax almost instantly:
-
Motor neurons stop firing to the flexor.
-
The muscle goes slack.
-
There’s no longer anything opposing the extensor’s pull.
This acts like flicking open a latch — the energy stored in the semilunar processes unleashes, accelerating the tibia outward.
The Potential
AI on AskNature
This page was produced in part with the assistance of AI, which is allowing us to greatly expand the volume of content available on AskNature. All of the content has been reviewed for accuracy and appropriateness by human editors. To provide feedback or to get involved with the project, contact us.
