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© Copyright 1996, Jim Loy
It is well-known that a scientist (supposedly) once said that physics (or science) shows that a bee can't fly (or maybe that a fly can't be?). Bees do fly, by the way. This is a popular example of how stupid scientists can be. It is hard to disagree with that. There is some small amount of truth to the statement that a bee can't fly (see addendum, below). But, the statement demands to be misinterpreted, and that is far from being scientific.
Physicists sometimes derive equations that apply to airplanes. An airplane the size and shape of a bee could not fly. In other words, the wings of a bee cannot support the bee at the speeds that a bee normally flies, if the wings are held out motionless. Perhaps this hypothetical bee is being propelled by a tiny propeller on its nose. Well, such a bee would drop from the sky like a bee with stiff wings and a propeller on its nose. By the same equations, a helicopter cannot fly either.
What keeps an aircraft aloft is not forward speed, but rather the motion of air over, and under, the wings. Forward motion keeps air moving over an airplane's wings. But, against a strong head wind, an airplane can even remain aloft while flying backwards. The bee's (and the helicopter's) wings are not motionless, the wings themselves move (very rapidly) in order to make the air pass over the wings. Bees and helicopters (and hummingbirds) are famous for hovering motionless, because of this.
A real scientist would say that a bee can't glide. But wait, if he were going about 100 mi/hr ... never mind.
By the way, helicopters do have wings. Helicopters are also known as rotary-winged aircraft.
Also, I have seen it mentioned in books that a hummingbird is the only bird that can hover motionless. I've seen a couple other species of birds, including a hawk, remain motionless for several seconds without a head wind.
Addendum:
I received email which further clarified the above situation. A bee is very small. And, at that size, air acts as a much more viscous fluid than it does for airplanes and helicopters. So the laws of aerodynamics are quite different for bees and other insects.
I was informed, by email, that the hawk that remains motionless is probably an American Kestrel, a kind of falcon. It seems that this is one of the main ways that it hunts, getting a fix on some small mammal before diving. This behavior is called kiting. I have recently seen several tiny sparrows hovering among weeds, perhaps feasting on insects on the weeds.
I have also read that songbirds cannot sing while flying. Well, today I heard one singing with great vigor, while flying. So I rushed home to share that with you. It was chirping loudly, but that probably did not officially qualify as song. That one was a robin, which seemed to be distressed, nothing like its normal song. But today I saw a small warbler chasing a blackbird, and it was actually singing, just like its song when it perched at the top of a tree.