Researchers Crack the Case of Why Flies Are Hard to Swat

By Eliza Strickland | August 29, 2008 7:31 pm

flyIn a match-up between an annoyed human brandishing a fly swatter and a buzzing fly, who wins? As most people know from frustrating experience, all too often the fly easily evades the human’s swat, and buzzes merrily into another region of the room. Now, using a high-speed camera, scientists have determined just how the fly makes its astoundingly effective escape.

Biologist Michael Dickinson used a video camera that shoots 5400 frames per second to record a fly’s precise motions when threatened with a swatting. The video showed that as a threatening object moved towards the fly from one direction, it shuffled its feat and positioned itself to take off in the opposite direction–all within 200 milliseconds. “They perform an elegant little ballet with their legs,” says Dickinson. “They move their legs around to reposition their bodies so that when they do jump, they will push themselves away from the looming threat” [NPR].

The study, published in the journal Current Biology [subscription required], illustrated a precise series of actions, in which the insects shuffled their feet and shifted their weight so that their center of mass was just above their two middle legs, which they use to jump [ScienceNOW Daily News]. All those actions took place a full 100 milliseconds before the flies beat their wings to escape, researchers say. While the sheer speed of the process is remarkable, researcher are most impressed with what it indicates about the fly’s poppy seed-sized brain: that flies have not only lightening-fast visual processing, but can use the information they gather to plan an appropriate escape.

How, then, can we defeat these fiendishly clever winged adversaries? The right approach is to aim not at the insects themselves because they are extraordinarily good at anticipating where exactly your blow will land. “It is best to aim a bit forward of the fly’s starting position, to anticipate where it is going to jump when it first sees your swatter,” said Michael Dickinson [The Times].

Image: Gwyneth Card and Michael H. Dickinson



  • Chad

    Jackie, Will you marry me?

  • Anthony

    Suck a fat one, both of you. This is cool stuff. These scientists have no experience in wars, starvation or economics. Just because there is a world of crap doesn’t mean people shouldn’t be able to do things that are interesing. And besides Jackie, what are you doing to fix any of the problems you listed above? Stop whining, you might learn something you didn’t know before.

  • Lisa

    And dear Jackie, although I’m pretty sure Anthony covered everything I want to say, I’m pretty sure you’d earn a bit more respect if you stopped molesting the caps lock button. Just so you know, the world will always suck, so get over it and learn something every now and again just for the heck of it.

  • Darrell

    Seriously Jackie, you are just like that fool Ambrose Bierce who mocked the people who tried to discover as to what a magnet does exactly. He mocked them, unknowing that in a even twenty or thirty years time magnets where used in nearly everything electronic. This right here can explain as the why a fly (insects are robets mind you, they are a simple bio-mechanical machine) does what it does. The implications are endless on the micro-structure oh certain miniature machines, processesor and about a dozen other possible applications. You have no perspective, you are merely a frog in a pond, with only a micro-sized view of the world. It doesn’t enrich you only because you will never put it to use and you will never attempt to help those starving people directly by creating or doi9ng something worthwhile. So while you nay-say those minds who discover, you will only plod through life contributing nothing but cynicism and poor vision.

    Please, imagination is key here.

  • Darrell

    Man, my apologize for the typos and poor punctuation, never write and eat at the same time..

  • Stoney

    Why are all of you squabbling when there’s a fly to kill!

  • Carlyle

    Many years ago I discovered that aiming just behind the fly was the most successful strategy. They jump backwards, not forwards, or are Aussie flies different?.

  • Mike

    I think flies are part of the black hole phenomenon. So the next question is, how fast can a fly…fly????

  • Tim

    Dear Jackie,

    I understand why you feel that way, but this is an important discovery. This is not about fly swatting but it sure helped to get you and I to read the article. It really is about how elegant a solution nature has given the fly to survive. Flies are relatively simple organism that can do incredible feats. There is something very elegant here and if we can understand the underlying mechanisms that have EVOLVED (more to support evolution!) in this organism, we come closer to understanding our own makeup. And at the very least, we can learn to use the the visual processing capabilities of this little insect to better humanity. Science is our last and perhaps only tool against those that believe in an invisible super being who says that he (not she) loves humans but inflicts great suffering unto them.

  • Chuck Norris

    When I kill flies, they’re dead before they even begin they’re little ‘shuffle.’ 100 milliseconds is 99 milliseconds too slow for my round house kick.

  • Dart

    Now I know to use two fly swatters instead of one to smash them. A rubber band is more accurate since they never see it coming. I have been able to get them flying through the air with a rubber band.

  • Rik Hansel

    Maybe those scientists will also explain why and how as a little kid of eight I easily caught flies with my bare hands. I used to wait until one would rest on the table top and then I would quickly move an open palm towards it and quickly close my fist entrapping the fly in my hand and then with all the force I could muster hurl the fly to the floor and then squash it.

  • Kristine

    ahhh, Rik Hansel! you touch them with your HANDS? i touched one by accident, and it felt hairy and alien to me.

    LOL at chuck norris.

    i feel like im the only kid in here….well dont mind me, im just looking for an article for my summer assignment…

  • Brewer

    There was a time in the recent past when I read about the act of coating a fly’s head with a molecular-thin layer of gold. Of special interest was the eye, as poking out from between all those eye-cells, were hairs – feelers, the purpose of which was believed to sense the change in air pressure as a swatter was brought down.

  • Mike

    Wow. I can’t believe that anyone would have enough time and bile to bother to write something negative about an article they didn’t have to read if they weren’t interested in the first place.
    I would also like to say that no one reading this magazine has a problem with evolution (neither, I might add, would anyone who has actually read the Bible and understands what It says). God and science are not opposing concepts!!!

  • Anonymous

    Wow. I’m surprised this wasn’t known already.

    I have a Chinese friend who did kung fu. He said he used to watch flies every day when he was a kid to see how they took off, so he could catch them.

    He explained to me how they take off backwards to evade, and he had a technique where he could catch them between his curled index finger and the back of his second finger.

    I used to watch him do it, and he really could get them every time.

  • Bugged In West Texas

    I live in an area of a lot of cattle and occasional rain. This equals a lot of practice swatting flies–even with screens & air conditioning. I’ve always claimed that if you aim just ahead of the fly (in the opposite direction that you’re coming from) you’ll almost always get the suckers. Now I know why I’ve always been so accurate. Besides, I’ve read that they carrie H. pylori on their feet and that eating food they land on can lead to ulcers. (So it wasn’t the stress at work, but the food from the company picnic that gave you ulcers…)

  • stephen hawking

    the best way to swat a fly is from directly overhead (of the fly). the fly’s excellent motion detectors are designed to be sensitive from motion around the fly, so a blow coming from overhead will be less detectable. you can even bring down your hand slowly from directly overhead and the fly won’t move, try it.

  • Vineesh

    I faintly remember reading a discover magazine article about 19 years back that the best way is to position hands 1 above the fly and clap, that will get the fly. I tried this successfully then. Will try this again in the next fly season.

  • Vineesh

    Sorry, did not notice the typo earlier. I faintly remember reading a discover magazine article about 19 years back that the best way to swat a fly is to position hands 1 feet above the fly and clap.

  • Richard Wilkinson

    Something on the bottom of the world happen in different directions. My dad would catch fies seemingly absent minded while doing what ever he was doing, after 65 years of practice I caught one by one its legs as it flew by.

  • modernrocko

    Ahh.. I love you Discover commenters. You always handle flames and internet trolls exactly the way I would. :)

  • Arous

    One day this information may lead to a infinitely renewable energy source that costs pennies to produce, you just never know…

  • the merlin

    I offer this simple and effective method of killing flies- use an old army surplus flame thrower you probably have collecting dust in the basement. works not only on flies, but all other household pests, except maybe cockroaches.

  • Mark

    Jackie’s message is sarcastic. Perhaps she is not capable of expressing herself directly and with reasoning.

  • Sp00t

    Dammit, Chuck Norris, I was drinking when I read that, and now my nose burns.

  • Mr. Miagi

    Chuck Norris and his round house is a wanna be. I use chopsticks to catch flies. LOL

  • g shock frogman

    I use laser mental focus and stare the fly down until it simply just gives up and dies!

    Actually my boxer (dog) is awesome fly catcher! He just messes up other things when he is jumping around after them because he is so big!


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