Bumblebee Flight Does Not Violate the Laws of Physics
There’s an oft repeated “fact” that the humble bumblebee defies all known laws of physics every time it flaps its tiny little bee wings and ascends to the sky. Now obviously this is false, since, well, bumblebees fly all the time and if every time a bee took off it was tearing physics apart, we’d probably realize that was the case when two thirds of our population disappeared after being pulled into tiny, bee-shaped black holes. And, certainly if this was the case, every physicist dreaming of a Nobel Prize would be devoting all their time to breaking the code of bumblebee flight in order to disprove some bit of our understanding of physics. That being said, if you work out the math behind the flight of the bumblebee, you’ll find that it actually shouldn’t be able to fly… so long as you don’t take into account all the relevant factors, which seems to be how this myth got started. Basically, if you calculate it all assuming bumblebees fly like airplanes, then sure, the bumblebee shouldn’t be able to fly. But, of course, bumblebees don’t fly like airplanes.
So where and when did this myth start? The often repeated story goes that many years ago an engineer and a biologist were having dinner and a few drinks, after the topic of conversation turned to each person’s respective field. The biologist asked the engineer to work out how a bee flew- scientists partied wicked hard back in those days. The engineer, keen to show off his skills, quickly jotted down a few calculations and came to the conclusion, that holy crap, a bee shouldn’t be able to fly.
Today, the story is fully ingrained in pop culture and many sites and people without looking into the matter, repeat it as fact, even though one wonders how such a drunken mathematician had the pertinent numbers on hand to perform such calculations on the spot… Hell, the Dreamworks Animation film, Bee Movie, with a budget of $150 million apparently couldn’t spare a few bucks to consult a physicist on the matter, and opened with a variation of the “bee’s shouldn’t be able to fly” myth on a title card, and that’s a film aimed at children, in 2007! Man, we really should be investing more money in schools or at least more factually accurate bee based movies.
As to the origin, it’s always possible, albeit somewhat unlikely, that a drunken scientist did indeed make a “back of an envelope (in some versions it’s a napkin) calculation” that proved bee’s shouldn’t be able to fly. An origin theory with a tad more documented evidence behind it, pins it on a French book published in 1934, Le vol des insectes, which makes passing reference to that fact that simple calculations yield a result that suggests insects, not just bumblebees, shouldn’t be able to fly. Some say it was German physicist Ludwig Prandtl who was responsible for popularising and spreading the myth amongst his peers, whereas others claim that the original calculations were made by one Jacob Ackeret, a Swiss gas dynamicist.
In the aforementioned earliest known reference to such an idea, Le vol des insectes, Antoine Magnan, the author, claims the calculations, in regards to insects disobeying the laws of physics, were made by his friend and assistant, André Sainte-Laguë. Of course, the author should have been skeptical on the accuracy of his friend’s calculations and assumptions given that many insects can fly, but here we are. So while we can’t be sure he was truly the first, the first known calculations on the subject were made by Sainte-Laguë, though this fact doesn’t necessarily mean that another physicist didn’t do similar calculations during a drunken argument, which is good because we like that part of the story. What isn’t known is how the fact first eked into the public consciousness, and it’s likely we’ll never find out due to it being so long ago.
As for the calculations themselves, scientists, engineers and entomologists have gone to great lengths to discredit them, as the original calculations failed to take into account a number of facts about the bee. Most pertinent of these is that bumblebees don’t fly like a plane and they don’t have stiff, rigid wings. With that in mind, the original calculations, which were based mostly on the surface area of the bee’s wings and its weight, aren’t really applicable, since they neglect several factors that need to be taken into account for an accurate calculation. For example, “the effect of dynamic stall“, which would take too long to explain in this article, which is already creeping up on “too long”. So I’ll just briefly say that “Aerodynamic bodies subjected to pitching motions or oscillations exhibit a stalling behavior different from that observed when the flow over a wing at a fixed angle of attack separates” and then refer you to the following if you’re interested in reading up on the subject, which is actually pretty surprisingly interesting; although I was technically being paid to read it, so perhaps that coloured my view on it: Dynamic Stall
The reality is that bees and comparable insects fly in an incredibly complex way that utilises, get this, mini hurricanes! We’ll link all this stuff at the bottom in the references if you’re interesting in the nitty gritty physics, but in lay terms, bees fly by rotating their wings, which creates pockets of low air pressure, which in turn create small eddies above the bee’s wing which lift it into the air and, thus, grant it the ability to fly.
To find this out, scientists have conducted a variety of tests using bees, the most awesome one being by Chinese scientist, Lijang Zeng and his team, who devised system comprised of lasers and tiny mirrors glued to bees back in 2001. This experiment was deemed superior to previous tests, as it didn’t need to use tethered bees (which fly differently) and because it contained lasers, which is of course super cool. We’re fairly certain that a laboratory full of Asian scientists firing tiny laser beams at bees covered in shiny body armour is going to be the next big Syfy channel hit, so remember that you heard about it here first.
In fact, the way bees and other comparable creatures fly is so efficient and causes so little drag, that research into the subject has been backed by various militaries in an attempt to mimic this method of flight with our own tiny insect-like robots, which is just a recipe for another Syfy hit.
So, around 80 years ago a scientists or mathematician of some sort made a rough, mistake filled calculation that claimed bees couldn’t fly. Fast forward almost a century and scientists today are still trying to erase that mistake from the public consciousness with increasingly complex experiments to prove the simple fact that bumblebees can, in fact, fly, and that this doesn’t violate any of our understanding of the laws of physics. The fact that they even had to bother doing this when they could have simply pointed out of the nearest window, with their palm firmly planted on their foreheads, at bees flying around, perhaps says a lot about the gullibility of our species. In the end, as I make my living off dispelling such myths, I’m not complaining. 😉
- 10 Amazzzzzzing Bee Facts
- How Honeybees Keep Their Hives Warm Given That They are Cold Blooded
- Honey Can be Used for a Variety of Medicinal Purposes
- What the “Bee” in “Spelling Bee” Means
- Helicopters Won’t Drop Like a Rock if the Engine Dies. They are Actually Safer than Planes in this Scenario
- Lasers illuminate the flight of the bumblebee
- Explained: The Physics-Defying Flight of the Bumblebee
- Brown University: Vibrations lecture. PDF
- The Bumblebee, Engineering Pathway.
- Flight of the Bumblebee
- Dynamic Stall
- The Earwig’s Tail: A Modern Bestiary of Multi-legged Legends
- The secrets of bee flight
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