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
the planet was slowly consumed by millions of initially bee-sized 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 and in the process
forever changing our understanding of the way the universe works.
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
that it’s a bee.
So what’s going on here and how did this myth get its start?
The oft’ repeated story goes that many years ago an engineer and an entomologist went to
a bar and were having a few drinks, and at one point the entomologist turned to the engineer
and said “Why the long face?”….
Wait, wrong story…
He actually asked the engineer to work out how a bee managed to fly despite its tiny
little wings- 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.
While it's always possible, albeit unlikely, that a drunken engineer did at some point
make a "back of an envelope calculation" that proved bee's shouldn't be able to fly, there
is no documented evidence supporting the aforementioned story.
As far as documented evidence goes, we now turn to 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 nearly all winged insects, not just bumblebees, shouldn't be able to
fly.
Author Antoine Magnan states in Le vol des insectes, that the calculations with regards
to insects disobeying the laws of physics were made by his friend and assistant, André
Sainte-Laguë.
From here, what isn't known is how this supposed fact first eked into the public consciousness
as Le vol des insects wasn’t exactly an international best seller.
It perhaps isn’t too much of a stretch that this was read by a few professors, who then
repeated it to students, some of whom became professors and the cycle repeated.
This sort of thing happens all the time.
For example, the co-author of this piece had many a mathematics professor who would tell
the anecdote that the reason there is no Nobel Prize for mathematics is because a mathematician
stole Nobel’s girl at one point, which isn’t true in the slightest.
More on this in an upcoming video.
Going back to bee flight, 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- and please make sure you’re sitting down before you hear
this next part because it’s going to come as quite a shock- bees don't fly like airplanes.
Just as important is that they don't have stiff, rigid wings when flapping.
With that in mind, the original calculations, which were based mostly on the surface area
of insect wings and their weight, comparing this to what sort of lift this could produce
using models applicable to the way fixed wing aircraft fly, aren't really applicable.
The reality is that bees particularly fly in an incredibly complex way- in an overly
simplistic nutshell via flapping their wings more or less front to back, while simultaneously
rotating them appropriately to create that lift and, in fact, also creating little low
pressure vortices in the air above their wings to further help with said lift.
This front to back motion also allows them to create lift both on the forward and back
strokes.
To find this out, scientists have conducted a variety of experiments using bees, the most
awesome one being by Chinese scientist, Lijang Zeng and his team, who devised a 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
(so in this case the bees flying more naturally) and we can only assume because the experiment
included lasers, which are always necessary for an experiment to be considered scientific.
In fact, 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.
But in any event, the way bees and other comparable creatures fly is so efficient, 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.
(If you’ll excuse us, we have a series bible and a pilot episode to write.)
Bonus Fact: Moving on from bees to another insect that
has a particularly pervasive myth associated with it- cockroaches.
You've probably heard that "the only living thing that would survive a nuclear war would
be cockroaches".
It has even been suggested that cockroaches can survive the amount of radiation at ground
zero of a large nuclear explosion, though of course, not the explosion itself.
The truth is, however, that while cockroaches can withstand ionizing radiation bursts about
10 times as high as humans, they actually are relative light weights in that arena.
In fact, it only takes a burst of about 1,000 rads to significantly interfere with a cockroaches'
ability to reproduce, which would obviously be the eventual end of the cockroach in the
long run.
For reference, this is about the level of radiation at around 15 miles from Hiroshima
directly after the bomb was detonated.
Further, at burst levels of around just 6400 rads, about 94% of immature cockroaches will
die and at burst levels around 10,000 rads, most adult cockroaches will not survive.
While this is very impressive by human standards (humans only being able to survive about 400-1000
rads before death), it's decidedly unimpressive by insect standards; most insects can survive
much higher rates than the cockroach, according to the United Nations Scientific Committee
on the Effects of Atomic Radiation, who, when they aren't spending their time trying to
spit out their name, apparently enjoy zapping various living things with ionizing radiation.
Squeal piggy!
So who are the actual living creatures that would inherit the Earth after a world-wide
nuclear war?
Well, it has been shown that fruit flies take around a burst of 64,000 rads to kill.
More impressive than that is the flour beetle which can withstand up to around 100,000 rads
before dying.
Even better is a type of wasp, the Habrobracon, that can survive bursts as high as 180,000
rads!
These all get beat by the Deinococcus radiodurans microbe.
This bacteria can survive radiation levels as high as 1.5 million rads at room temperature
and nearly 3 million rads when frozen, such as during a hypothetical nuclear winter.
It isn't entirely clear where the myth that cockroaches were impervious to ionization
radiation got started, but it seems to have been largely popularized by anti-nuclear activists
in the 1960s who often used the cockroach in their slogans and campaigns.
For instance, in a New York Times advertisement sponsored by the National Committee for a
Sane Nuclear Policy: "A nuclear war, if it comes, will not be won by the Americans … the
Russians … the Chinese.
The winner of World War III will be the cockroach."
One thing also important to explicitly point out here though is the previously stated numbers
don’t quite tell the whole story in a nuclear fallout type scenario.
You see, insects are so good at surviving exposure to ionizing radiation primarily because
their cells don't divide that much between molting cycles, and cells are most susceptible
to damage by ionizing radiation when they are dividing.
Given that a typical cockroach only molts about once a week and its cells only divide
around a 48 hour period during that week, about 3/4 of the cockroaches exposed would
not be particularly susceptible to damage by ionizing radiation, at least, relative
to those whose cells were currently dividing.
As you might have inferred from this, this means that if the radiation experienced by
these cockroaches was consistent over a long period of time, they are going to be significantly
more susceptible to problems than the numbers we previously quoted suggest, as those numbers
were from specific bursts of radiation over a short span.
On the other hand, humans and other mammals are very susceptible to this type of radiation
as we experience cellular division all the time.
This is also one of the reasons radiation is effective at such low doses at killing
cancer cells, relative to what is required to damage healthy cells.
Cancer cells divide much quicker than most other cells in the human body; thus, you can
often kill the cancer cells faster than the healthy cells and hopefully find a happy medium
where all the cancer cells die, but enough of the healthy cells remain and are undamaged
enough for the person to continue living on more or less as before.
In any event, while cockroaches may not be well equipped to survive nuclear fallout,
relative to various microbes and most of their insect brethren, these little critters are
extremely hardy, with fossil records of cockroaches dating all the way back to 300 million B.C.,
which pre-dates dinosaurs by around 70 million years.
Cockroaches have also been shown to survive with their heads chopped off for nearly a
month.
Further, they can survive as much as 45 minutes without oxygen and can survive on very low
quality of food, such as the glue on a postage stamp, or cellulose, and very little of this
to boot.
They can even survive for quote some time by simply eating each other, if needs be.