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Fruit Flies, Fighter Jets Use Similar Evasive Tactics When Attacked

vinces99 writes: "When startled by predators, tiny fruit flies respond like fighter jets – employing screaming-fast banked turns to evade attacks. Researchers at the University of Washington used an array of high-speed video cameras operating at 7,500 frames a second to capture the wing and body motion of flies after they encountered a looming image of an approaching predator (abstract). 'We discovered that fruit flies alter course in less than one one-hundredth of a second, 50 times faster than we blink our eyes, and which is faster than we ever imagined.' In the midst of a banked turn, the flies can roll on their sides 90 degrees or more, almost flying upside down at times, said Florian Muijres, a UW postdoctoral researcher and lead author of the paper. 'These flies normally flap their wings 200 times a second and, in almost a single wing beat, the animal can reorient its body to generate a force away from the threatening stimulus and then continues to accelerate,' he said."

44 of 65 comments (clear)

  1. Anyone by mingot · · Score: 5, Funny

    Anyone who has ever had these little bastards in their house could have told you how good they are at evading predators.

    1. Re:Anyone by Anonymous Coward · · Score: 5, Funny

      I especially hate when you are about to nail them mid air and they release decoy flares.
      That shit burns!

    2. Re:Anyone by 50000BTU_barbecue · · Score: 1

      Yes, but they're also quite deaf. They seem oblivious to the vacuum cleaner. I've seen some fat, stupid fruit flies resting on my kitchen counter that *stay put* as their wings start to bend from the suction... Then, womp! down the hose and that's that.

      --
      Mostly random stuff.
    3. Re:Anyone by ByteSlicer · · Score: 5, Funny

      Still, we're lucky they aren't carrying any Stingers.

    4. Re:Anyone by formfeed · · Score: 1

      Anyone who has ever had these little bastards in their house ...

      .. like in Virginia Beach?

    5. Re:Anyone by fuzzyfuzzyfungus · · Score: 1

      It would actually be interesting to see if, given suitable advances in the design and construction of biomimetic robots, low-speed-but-lightweight-and-crazy-maneuverable becomes a viable strategy (presumably as a complement to a very high speed arsenal). Something with the maneuverability of a fly(especially a fly that also has a few small jets for bursts of thrust on maneuvers that exceed what its wings can provide) might well be able to walk right past missiles designed to intercept high speed conventional aircraft unless those missiles were minimally dependent on accuracy because of large warheads with lots of shrapnel and AoE. Much less useful against more prosaic rapid-fire-guns and flack; but something designed to hunt fixed wing aircraft could be in for a real surprise.

    6. Re:Anyone by fuzzyfuzzyfungus · · Score: 2

      I'm not sure if they are 'deaf' (and if they aren't, how much of their sensitivity-to-vibrations-in-fluid is actually 'hearing' and how much is 'touch' with their little sensory hairs) or if their range of stereotyped behaviors doesn't include predators that work by suction. There are some aquatic predators that are suction hunters, presumably becaues the fluid is denser; but nothing terrestrial comes to mind. If they evolved in absense of suction attacks, they presumably either are encountering something outside their experience, or running their protocols for high wind, when the vacuum cleaner attacks.

      The little bastards are brutally well optimized; but don't seem to have much general-purpose-cognition grafted on so their utility in the face of novelty is likely very, very, low.

    7. Re:Anyone by K.+S.+Kyosuke · · Score: 1

      Actually, my spiders don't have problems catching and eating them. Unless you meant MQ-1 Predators, that is. I've never observed a fly trying to evade those.

      --
      Ezekiel 23:20
    8. Re:Anyone by mikael · · Score: 1

      They are sensitive to sudden positive high-pressure air flow; flapping of a wing, motion of a bird. A continuous negative high-pressure air flow won't activate them.

      --
      Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
  2. Although by Anonymous Coward · · Score: 1

    "We discovered that fruit flies alter course in less than one one-hundredth of a second, 50 times faster than we blink our eyes"

    Almost as fast as a politician during an election campaign.

    1. Re:Although by OhSoLaMeow · · Score: 3, Insightful

      Why are politicians similar to flies?

      They both eat shit and bother people.

      (rimshot)

      --
      They can take my LifeAlert pendant when they pry it from my cold dead fingers.
  3. Check the slight angle change just after the roll by wherrera · · Score: 4, Informative

    There is a variable angle change just after the initial turn away from the threat that allows the fly to be unpredictable. Otherwise the predator can predict the fly will evade directly away and anticipate where the fly will be. Very clever.

  4. Flies need all the speed they can muster... by ggraham412 · · Score: 1

    The flies need all the speed they can muster, to evade the even more deadly dead cat helicopter.

  5. Clint Eastwood in "FruitFlyFox" by Freshly+Exhumed · · Score: 2

    Dr. Baronovich: "You must think in Fruit Fly."

    --
    I deny that I have not avoided attaining the opposite of that which I do not want.
  6. Don't reverse that by GrumpySteen · · Score: 1

    It's an analogy between two things, not a patent application.

    It's normal for the thing you're talking about to be mentioned first and said to be like the more commonly known thing. Reversing it would have people thinking that you're talking about jet fighters for the rest of the paragraph.

    1. Re:Don't reverse that by Oligonicella · · Score: 1

      It was a joke, not a serious comment.

  7. Are we sure it is JUST like a fighter jet? by Rich0 · · Score: 5, Interesting

    It sounds like they simply described the fly turning directly away from the predator and running, which is NOT what a fighter jet does (unless they just want to be shot down by a missile). At least, not unless they were already outside of their range (at that point, running is the best strategy).

    A fighter jet would make a sharp turn TOWARDS the attacker so as to cross his path at a sharp angle, which maximizes the velocity difference between them (velocity is a vector, and they are rapidly closing at an angle). This maximizes the amount of delta-V a missile would have to apply to intercept the aircraft, and in the event of a gunshot it maximizes the amount of lead angle that would need to be used (which is very difficult to pull off). Basically you try to ruin their opportunity to fire on you, so that you can get into a dogfight and hopefully get an opportunity to fire at them.

    See something bad and run away is a very intuitive strategy, and it probably makes a lot of sense in nature where predators have to make physical contact to hurt you. In a world of weapons where things like lead angles and enfilading fire come into play the optimum strategy may not be what a rabbit does when it sees a cat.

    1. Re:Are we sure it is JUST like a fighter jet? by Anonymous Coward · · Score: 4, Insightful

      Actually, I think the limit of the analogy was that both fruit flies and fighter jets use banked turns during evasive maneuvers. A banked turn is an obvious choice for a fighter jet, but when you get down to the size of a fruit fly, the aerodynamics are different and so it's interesting that this is still a preferred turning strategy.

    2. Re:Are we sure it is JUST like a fighter jet? by Rich0 · · Score: 2

      Actually, I think the limit of the analogy was that both fruit flies and fighter jets use banked turns during evasive maneuvers. A banked turn is an obvious choice for a fighter jet, but when you get down to the size of a fruit fly, the aerodynamics are different and so it's interesting that this is still a preferred turning strategy.

      I wouldn't take it for granted, but it makes a lot of sense in basic physics. Normally anything that flies has to produce a lift force directed upwards to counteract gravity. If you just turn it on its side the exact same force causes it to turn. So, while the wings could move in lots of odd ways, banking is a really simple solution to the problem of turning.

    3. Re:Are we sure it is JUST like a fighter jet? by X0563511 · · Score: 1

      Makes sense to me - the primary function of the wings is to provide lift "up" - so for a more effective turn you pivot so that the maneuver is always "up" before you execute.

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
    4. Re:Are we sure it is JUST like a fighter jet? by timeOday · · Score: 1

      Check the list of agencies sponsoring the research. This is just a little game you have to play to do research in the US.

  8. Awesome! by AioKits · · Score: 1

    Finally, an excuse to play Danger Zone by Kenny Loggins when I try and swat the lil bastards!

    --
    "Quote me as saying I was mis-quoted." -Groucho Marx
  9. Peppy Hare to Fly McClure by idontgno · · Score: 1

    In the midst of a banked turn, the flies can roll on their sides 90 degrees or more, almost flying upside down at times, said Florian Muijres

    "Do a barrel roll!"

    --
    Welcome to the Panopticon. Used to be a prison, now it's your home.
    1. Re:Peppy Hare to Fly McClure by idontgno · · Score: 1

      Damn autocorrect. "McCloud", not McClure.

      Fly McClure? "Hi, I'm Fly McCulre. You may remember me from such vermin-borne illnesses as cholera and anthrax."

      Sigh.

      --
      Welcome to the Panopticon. Used to be a prison, now it's your home.
  10. I always thought... by squiggleslash · · Score: 3, Interesting

    ...fruit flies like bananas. I stand corrected.

    --
    You are not alone. This is not normal. None of this is normal.
    1. Re:I always thought... by Plumpaquatsch · · Score: 2

      ...fruit flies like bananas. I stand corrected.

      More proof Marx was wrong!

      --
      Of course news about a fake are Fake News.
    2. Re:I always thought... by grep+-v+'.*'+* · · Score: 1

      ...fruit flies like bananas. I stand corrected.

      If *I* saw a giant banana with teeth flying towards me, I'd probably turn and run too.

      --
      If the universe is someone's simulation -- does that mean the stars are just stuck pixels?
    3. Re:I always thought... by tverbeek · · Score: 1

      Time flies like an arrow.
      Fruit flies like a banana.

      --
      http://alternatives.rzero.com/
  11. New Flash by digitalPhant0m · · Score: 1

    When shit gets attacked it tries to get out of harms way. Thanks Slashdot. Now I know.

  12. Wow... by nashv · · Score: 1

    Who knew that the best thing to do when something dangerous was coming at you was to get out of its way as fast as possible...

    It's cool that they observed the fly behaviour...but it's not the most deeply insightful finding.

    --
    Entia non sunt multiplicanda praeter necessitatem.
  13. They have got one flaw though by aliquis · · Score: 1

    "There's a bunch of fighter jets in my pickled cucumbers!"

  14. Re:and yet they can't avoid Apple Cider Vinegar by srussia · · Score: 2

    and yet they can't avoid Apple Cider Vinegar

    Give them time to evolve a defence against the Reality Distortion Field.

    --
    Set your phasers on "funky"!
  15. Don't paint your house yellow by formfeed · · Score: 1

    It will attract fighter jets.

  16. Fly voice by PPH · · Score: 1

    "Too close for missiles, switching to guns!"

    --
    Have gnu, will travel.
  17. Maverick by Nidi62 · · Score: 1

    Good thing they didn't try to perform a split-S; that would have had Charlie all over them. Everyone knows it's the last thing you should do.

    --
    The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
  18. Crazy Ivan by PPH · · Score: 3, Funny

    They always go to starboard in the bottom half of the hour.

    --
    Have gnu, will travel.
  19. How alike are they *really*? by GodfatherofSoul · · Score: 1

    Do they scream out cliches like "I can't shake 'im" and "I got a bogey on my six!"? And, do they have ambiguously gay volleyball matches after a sweaty dogfight?

    --
    I swear to God...I swear to God! That is NOT how you treat your human!
  20. Blink Speed by mbo42 · · Score: 1

    "... in less than one one-hundredth of a second, 50 times faster than we blink our eyes" 1/2 a second to blink?! or is the fly actually quicker than one-hundredth of a second?

    1. Re:Blink Speed by mbo42 · · Score: 1

      ... if the image in the article is a real one, from the 7500 frames per second camera, it looks like the turn may be completed in less than one-thousandth of a second. That makes the 1/50th of a blink sound better.

    2. Re:Blink Speed by Paradise+Pete · · Score: 1

      "... in less than one one-hundredth of a second, 50 times faster than we blink our eyes" 1/2 a second to blink?!

      You are ignoring the "less than" part. And as far as I can find, typical human blink duration is roughly 400 milliseconds

  21. What's awesome... by fyngyrz · · Score: 1

    ...is that something with the brain the size of a fruit fly can discriminate between a predator and a non-predator, and react defensively.

    We really need to figure out how brains work, lol.

    --
    I've fallen off your lawn, and I can't get up.
    1. Re:What's awesome... by mikael · · Score: 1

      I'm not sure they can discriminate between a predator and non-predator. They go by smell to find food and partners. Just about anything that is a dark shadow or moves relative to the background is a potential predator - either they get squished or eaten,

      They do vision by a method called "optic flow". Imagine everything you see is projected onto a hemispherical dome (like one of those IMAX theaters). The only way you can tell how the camera is moving is whether the picture rotates around a single point, a particular area of the picture gets larger or smaller and any combination of the two. How quickly different parts of the picture move tells them how near it is.

      --
      Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
    2. Re:What's awesome... by fyngyrz · · Score: 1

      Imagine everything you see is projected onto a hemispherical dome

      Everything *we* see is put on our retina upside down and with a hole in it, and gets really crappy at the edges. Brainz. No wonder zombies like 'em. :)

      --
      I've fallen off your lawn, and I can't get up.
    3. Re:What's awesome... by drinkypoo · · Score: 1

      We really need to figure out how brains work, lol.

      Or we just need to figure out how to maintain a blob of brain tissue for a long period... presumably you'd use a quorum of brains and have them vote on an action before you took it, majority rules to keep that instinctive speed

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"