Guiding BeeThe Evolution of Flight



Deforming the Wing Surface

Of course, every flying insect must be able to produce an airfoil geometry with its wings. Flat wings simply won't produce any lift. For this purpose, the wings are attached to several muscles similar to the muscles in our shoulders. These muscles flex various parts of the wings separately, so that the leading and trailing edges of the wings may be manipulated to create an efficient aerodynamic surface.

Some species, however, have taken wing torsion to new heights, so to speak. Echinomia grossa (sketch) can twist the leading edges of its wings through nearly 180 degrees so that the trailing edges point forwards. In the fantastic stunt manoeuver here depicted, this fly takes off backwards and sideways. This feat of sheer agility that cannot be matched by any bird or bat.

If you want to impress your friends at a party, here's how:

Find a housefly on any surface. Sweep your hand towards it from behind and catch it as it launches itself into your hand. Be sure, though, to be nice and let it go once everybody has realized that you very deftly caught a fly out of midair!
This little trick works because houseflies always take off backwards. Over the eons, the majority of predators have attacked flies face-on. The take-off, therefore, serves the housefly very well (except at parties).


The Evolution of Flight...5, March 1996