BBC article here.
he flies that have been chased by the fast-sighted birds will be evolving faster reactions to get away. Creating an evolutionary arms race that has gone on longer even than the existence of birds.
Prey flies have been evolving faster vision and reactions to escape predatory flies like the killer fly since they evolved flight. Next time you try inanely to swat a fly, try not to be so disheartened. Your lumbering, slow motion swats are being thwarted by hundreds of millions of years of natural selection letting the flies watch your attempts in slow motion.
and the classic book "To Know a Fly" can be found here.
the book is an argument about the need to support basic science experiments, even ones that seem stupid to ordinary folks... in this case, experimenting and observing the fly.
Like taxes, the fly is always with us. As a matter of fact, there are at the latest count, about 50,000 kinds of flies sharing "our" world. They include, to mention only a few, houseflies, fruit flies, soldier flies, snipe flies, small-headed flies, stiletto flies, blowflies, march flies, dance flies, horse flies, stable flies, black flies, tsetse flies, crane flies, hump- backed flies, bee flies, flat- footed flies, big-eyed flies, thick- headed flies, sand flies, robber flies, gadflies, dung flies, and louse flies. A motley and prolific crew!
A characteristic human reaction to flies is to eradicate them....
But the next time a fly lands on the edge of the dinner table to rest and to rub its feet together in anticipation, stop before you mash it into the woodwork with a fly swatter (this is one insecticide against which a fly will never develop resistance). This little beast accomplished one thing that you and I can never accomplish; he flew there!
One of the smaller flies weighs about seven millionths of a pound. He is equipped with two reinforced membranous wings which must serve the dual function of wing and propeller. Failure to take into account this dual function of insect wings led to the famous miscalculation proving that bees could not fly. The bee had been analyzed as a helicopter. So it is with the fly. To stay airborne and move forward, the fly must beat his wings as much as two hundred times a second. By comparison, the hummingbird beats about seventy-five times a second; the rattlesnake rattles about one hundred times a second on the hottest days. The fastest repetitive muscular contractions that you and I can produce occur at the rate of about ten times a second. The fly has other wondrous accomplishments, too, not the least of which is being able to land on the ceiling.
For years, controversy raged as to whether he managed this by executing a half-roll or an inside loop. As a matter of fact, he does neither. He flies close to the ceiling in a normal position, then reaches up and back over his head with his front feet till they touch the ceiling, whereupon he somersaults over into position. The incredible nimbleness- of flies is no secret to anyone who has attempted to catch one in his cupped hand, nor is their astronomical power of reproduction to anyone who has tried to eradicate them.
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