Sometimes the design built into the world to make it inhabitable can serve as irritations to us when taken out of context. That is certainly true of flies. Flies provide an important function in the processing of organic materials in nature. By laying their eggs on decaying carcasses or decaying organic waste, flies speed up the removal of dangerous materials from the environment.
The fly’s amazing ability to fly quickly and to land almost anywhere, even upside down on the ceiling, shows great engineering in design. How does a fly land on the ceiling anyway? Slow motion close-up recordings show that the fly approaches the ceiling with the top of the fly facing the ceiling. They bring their forelegs above their heads and make contact with the ceiling. Once their front legs are stuck they tuck their bodies and let the momentum roll them to a safe landing as their remaining legs make contact. They are basically doing a flip in order to land upside down.
A close look at these versatile insects shows how incredibly well deigned they are.