Have you heard the old saying, "Dogs have fleas to keep them from worrying about being dogs?" Well, it's true that dogs spend a lot of time scratching, and for good reason, flea bites itch. Fleas can cause their host animals to be unthrifty. thus, another saying, "The fatter the fleas, the leaner the dog."
Fleas are among the most modern of insects. Some scientists believe that fleas are just flies that have lost their wings. Fleas live on mammals. So they can move easily through the hairs on their hosts, fleas are flattened from side to side.
Adult fleas are known for their jumping ability. A flea can leap up to 13 inches. If a human could do as well, the world long-jump record would be nearly 800 feet. Such a comparison is not fair. Fleas have rubber-like pads at the base of their back legs. These pads are compressed when the flea is preparing to leap. Thus, flea jumps are spring aided!
Immature fleas live in the nest of the host and feed on feces and other organic materials. Before changing into adults, young fleas enter a resting stage that can last for months. The fleas emerge from the resting stage when a host animal enters the nest. Either the motion or the heat from the hosts body triggers the emergence. Such behavior ensures that a food source is available to the newly-emerged and hungry flea.
Some fleas are named after specific animals such as the cat flea and the dog flea. However, most fleas will feed on any warm-blooded animal. In fact, the most common flea found on dogs is the cat flea, not the dog flea.
It is hard to be positive about fleas, but they have been trained to pull carts and perform in flea circuses. The training is the easy part, but finding a harness to fit a flea is another matter.
Humans have long been bothered by fleas. In the Middle Ages, ladies even wore "flea furs." This piece of fur was worn around the neck as an attraction for fleas. The collar with its collection of fleas could then be removed and the fleas destroyed.
Ogden Nash recognized the long association of humans and fleas in his poem entitled "Fleas." The entire poem is "Adam Had'em."