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Dog flea Dog flea Fleas are tiny wingless insects, with mouthparts adapted for piercing skin and sucking blood. The flea's body is hard and covered with many hairs and backwards-pointing spines. The tough body can withstand great pressure. They live off the blood of mammals and birds. Most flea species have bodies perfectly suited to the hair or feathers of their host species. Fleas go through the four life-cycle stages of egg, larva, pupa and adult. Adult fleas must feed on blood before they can reproduce. Fleas have a powerful “trigger” in their hind legs that allows them to travel over 150 times their own length in a single leap.

Human flea, greatly magnifiedHuman flea, greatly magnified


Covered in tiny bristles and equipped with spines on its head and thorax, a flea is perfectly designed for the job of clinging on to another animal while it runs, flies or swims. Its flattened body is the ideal shape for “swimming” through the fur or feathers of its host. Fleas that live on hedgehogs and porcupines have widely-spaced spines that hook around their hosts' spines.

The flea uses its saw-like mouthparts, called stylets, to pierce its host’s skin and suck up its blood. It even has a hammer-like mechanism embedded inside its head which it uses to drive the stylets into the skin with great power over and over again until they reach a blood vessel. 
Hen flea, or European chicken fleaHen flea, or European chicken flea

There are about 2000 known species of flea.

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