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Flea's Jump Analyzed By Scientists
The age-old mystery of how fleas jump 100 times their height has been solved - and it's their toes not legs that are key.
It has long been known that fleas store the energy needed to catapult themselves up in an elastic-like pad above the hind legs.
But there has been 44 years of constant debate about how the tiny insects use this energy to travel around 100 times their height.
And now, in the first study of its kind, two researchers used high speed recording equipment to examine the exact movements involved and proved that they push off using their toes.
Using hedgehog fleas, they filmed 51 jumps from 10 of the animals.
In the majority of jumps, two parts of the flea's complicated legs - the toe and knee - were in contact with the ground for the push off.
But in 10 per cent of the jumps, only the toe touched the ground.
The duo could see that the insects continued accelerating during take-off - even when the knee was no longer pushing down - and those that jumped without using the knee accelerated in exactly the same way as those that jumped using both the knee and toe.
Furthermore, when they looked at the flea's leg with scanning electron microscopy - a microscope in which a finely focused beam of electrons is scanned across them - the shin and toe had gripping claws but the knee was completely smooth - so it couldn't get a good enough grip to push off.
They suspected that the insects push down through the shin onto the toe, as previous research has suggested, but they needed a mathematical model to reproduce the flea's movement and prove their argument.
Source = The telegraph
George Williams,
General Manager - Staff Entomologist
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