A Flea Can Jump Over a Hundred Times Its Own Height
Fleas are small jumping parasites. Their jump uses a spring made of an elastic protein rather than muscle power alone.
Fleas are small wingless insects that feed on blood. Their jump is not muscle-powered in the ordinary sense: a flea slowly compresses a pad of *resilin*, an almost perfectly elastic protein, then releases it in under a millisecond, giving an acceleration muscle alone could never produce. It is a catapult, not a leg. *A flea in your ear* means a sharp rebuke, from the maddening irritation the insect causes.
- A jumping parasite. *The dog has fleas.*
- Flea market — a second-hand market. *A Sunday flea market.*
- A flea in your ear — a sharp rebuke. *He sent her off with a flea in her ear.*
- Resilin — the elastic protein. *A pad of resilin.*
- Flea-bitten — shabby. *A flea-bitten hotel.*
Word forms
| Form | Word | Example |
|---|---|---|
| Singular | flea | One flea. |
| Plural | fleas | Many fleas. |
| Compound | flea market | A flea market. |
| Adjective | flea-bitten | Flea-bitten. |
| Old English | flea | A flea. |
- The cat needs treating for fleas.Pests.
- We found it at a flea market.Second-hand.
- Resilin stores the energy for the jump.Biology.
Why flea market is called that
- French *marché aux puces*, market of the fleas, in Paris
- The name suggested second-hand goods old enough to harbour them
- English borrowed it as a direct translation in the 1920s
- Car boot sale — the British near-equivalent
- Both sell used goods from temporary stalls
Old English *flea*, from a Germanic root possibly related to a word meaning to flee, from the insect's rapid escape.
How high can a flea jump?
Around 18 centimetres, which is over a hundred times its own body length.
Why is it called a flea market?
It translates the French marché aux puces, a Paris market whose second-hand goods were old enough to be suspected of harbouring fleas.