The common black housefly, we all hate them, they are dirty, annoying and insidious, but like every form of life on this planet they are a product of nature and of course, evolution.
I'm not going to dwell on the subject of whether or not these
creatures are a necessary part of the balance of nature, but I
am going to write about a few observations I have made that I've
not seen mentioned anywhere else.
[Who else would even care I hear you say?]
Have you ever noticed that when one of these pests lands on you and you flick it off, how it whizzes away does a few aerial aerobatics, double axels and triple salcos only to return to exactly the same spot. How on earth do they do that? Considering their size, it's the equivalent of a human being travelling many hundreds of meters doing zigzag and circular maneuvers in a blank landscape and returning back to exactly the same spot. These virtually brainless creatures do it in a 3 dimensional landscape. As for why they do this, I can only surmise that if the first landing is detected and they're flicked away they stand a better chance on the second attempt since the landing site may have been de-sensitized, just a thought.
Another housefly observation is to do with numbers. I'm certain that the number of black houseflies in any given room on any given day is fixed. I'll explain, you know the scenario, there are a number of houseflies buzzing aimlessly around the ceiling hung lampshade [houseflies seem to have an affinity for ceiling hung lampshades], let's say there are five. OK, now eliminate one and see how long it takes for the number to return to five, it won't be long and it won't become six no matter how long you wait [that day]. Take out four, and in approximately the same time the number will return to five.
The other strange thing is that the optimum housefly number appears to change from day to day, but eliminating any number of them will still result in the same number of flies returning for that day. So if it's say a 'ten fly' day it will be a ten fly day all day, same for a two fly day and so on. The best way to test this is to eliminate flies by the time tested 'swat' method, using insecticide sprays just lengthens the time before the optimum number of flies for a particular day return to their lampshade inspection duties. Of course, if you have the time and the inclination.....