Now Cambridge scientists have finally cracked the mystery of how the minuscule insects leap so well.
In the first study of its kind, researchers used high speed recording equipment to show that the creatures push off from the ground, or the back of a family pet, using their toes.
Riddle solved: Cat fleas, like the one pictured, have multi-jointed legs which allows them to jump so high - to the fury of pet owners everywhere
It has long been known that fleas store the energy needed to catapult themselves into the air in an springy pad above their hind legs.
But experts have been divided whether they push off from their knees or feet.
Prof Malcolm Burrows said: 'We have finally shown, after all these years, how they do it.'
He added: 'They have to use more than their legs, because they have to use a catapult mechanism. There are virtually no insects, except those with long legs like the bush cricket, which can jump using just their legs.
'Their toes press on the ground, using the lever system of their legs. They have to grip the ground when they jump as they are using a huge amount of force.'
Dr Sutton said: ''We were concerned about how difficult it would be to make the movies because we are used to filming locusts, which are much bigger than fleas.'
However, the insects were easy to film because they stay still in the dark, and only jump when the lights are switched on.
In most of the jumps two parts of the insects' complicated legs - the toe and knee - were in contact with the ground during the push off.
But in one in 10 jumps, only the fleas' toes touched the ground.
The scientists could that the insects accelerated during take-off even when their knees were no longer pushing down.
And those that jumped with using their knees accelerated in exactly the same way as those who jumped using the knee and toe, they report in the Journal of Experimental Biology.
When they looked at a flea's leg in extreme close up using a scanning electron microscope the scientists saw that the shin and toe had gripping claws but the knee was completely smooth.
Prof Burrows said the fleas pushed down through the shin onto the toe. Their observations were confirmed with real, and mathematical models of a flea jump.
The study used hedgehog fleas, but the other common fleas use the same technique.
Most of the fleas in homes are cat fleas - a species that bites and feeds on people but which cannot breed on them.
The 3mm long bugs lay their oval shaped eggs on cat's fur, but the eggs dry and fall out, usually on the blanket or carpet when the cat sleeps.
The larvae hide from light and feed on dried cat blood. Once the adult has emerged from a cocoon, it jumps onto a host within seconds. The life cycle takes 30 days.
In 1967, Henry Bennet-Clark discovered that fleas store the energy needed to launch using a pad on their legs made of a stretchy substance called resilin.
They take off at 3mph and reach speeds as high as 4.3mph. ( dailymail.co.uk )
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