Siphonaptera: Fleas

(from the Greek: siphon = tube + aptera = without wings)

Siphonaptera are always wingless and have sucking mouth parts. They are flattened from side to side, have long legs and are good Fleajumpers. Their antennae are short and eyes are usually present. All fleas are parasites on the bodies of mammals or birds. Fleas lay eggs while they are on the host, and the eggs fall to the ground. When the larvae hatch they feed on bits of skin and hair in the host animal's lair or den. After several molts, the larva pupates. When the adult emerges from the pupa, it can go for months without food. Most flea species prefer one or two types of host, but they often will take experimental tastes of other animals. Dog and cat fleas will bite humans but will not live on them.

One of the most dread diseases of the past was bubonic plague, which was spread by fleas from rat to man and man to man. Bubonic plague, or the "Black Death," killed 70,000 people in London, England between 1664 and 1666. In the 1500's this Black Death claimed 25 million lives in Europe. Other diseases are also spread by fleas.