Flies

Flies are a common sight to most of the modern world. They are expert flyers and, unlike other flying insects, flies utilize flight through just one pair of wings. They have great eyesight and tiny hair folicles all over their body to sense when changed in the air occur. This would account for when you go to swing at one, it already has flown away. Flies generally develop from larva and consist of over 120,000 species. They begin life that way (think Maggot) and are often found on decaying substances like food or dead carcases. They stabalize their bodies in flight through the use of special organs called halteres. The fly family also consists of mosquitoes and midges.

Flies traditionally eat their food through a special tube that allows them to slurp up their prey. They prematurely digest their food outside of the body by applying a substance that breaks down the solid state of the prey. Other flies will just use mouth parts to bite and collect a meal of blood. The fruit fly will start off life as an egg (not as a larva), and will mature inside of aging fruit. Houseflies are have special secretions that allow them to land upsidedown on surfaces. It takes just a fraction of a second for the fly to fly up, land its front feet on the celing, flip it's body to allow the other 4 to stick and whalla! You have just pictured a fly landing on the ceiling.

Some flies have been known to spread diseases - perticularly flies like the African tsetse fly. These blood sucking flies move from prey to prey in search of a meal and will carry along contaminated blood to human carriers, only to have the human carrier unknowingly pass it on to another human through body fluid contact or blood transfusion.