Fleas Jump Using Stored Energy, Not Muscle
To jump is to push off the ground into the air. The best jumpers in nature do not rely on muscle power.
To jump is to push off a surface into the air. A flea cannot produce its leap with muscle alone: muscle contracts too slowly to deliver that much power. Instead it compresses a pad of resilin, a near-perfect elastic protein, and releases it like a catapult — the muscle does the work slowly and the spring returns it in an instant. Grasshoppers, click beetles and some frogs use the same trick, storing energy first and releasing it faster than muscle could.
- To leap. *Jump over it.*
- A leap. *A long jump.*
- A sudden increase. *A jump in prices.*
- Jump the gun — start too soon. *Jump the gun.*
- Middle English — of uncertain origin. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Verb | jump | Jumping. |
| Noun | jump | A jump. |
| Past | jumped | Jumped. |
| Agent | jumper | A jumper. |
| Compound | high jump | The high jump. |
- He jumped the fence.Leaping.
- A sharp jump in costs.Increase.
- Fleas use stored energy.Biology.
Nature's catapults
- Resilin is an elastic protein returning almost all stored energy
- Muscle contracts too slowly to power an extreme jump directly
- A latch holds the spring until release
- Fleas, click beetles and mantis shrimp all use the principle
- Engineers call it a latch-mediated spring actuator
Middle English, of uncertain origin, possibly imitative, recorded from the 1500s.
How does a flea jump so high?
By compressing a pad of elastic protein and releasing it like a catapult. Muscle alone contracts too slowly to deliver that power.
Do other animals do the same?
Yes. Grasshoppers, click beetles and mantis shrimp all store energy in a spring and release it through a latch.