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Science

Flies See the World In Slo-Mo, Say Researchers 176

Posted by timothy
from the sure-passes-quickly-as-the-decades-pass dept.
An anonymous reader writes "'The smaller an animal is, and the faster its metabolic rate, the slower time passes for it, scientists found. This means that across a wide range of species, time perception is directly related to size, with animals smaller than us seeing the world in slow motion.' No wonder it took so long to grow up!" Here's the original paper.
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Flies See the World In Slo-Mo, Say Researchers

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  • oh no (Score:1, Offtopic)

    by watcher-rv4 (2712547)
    Call the Judge Dredd!
  • by Russ1642 (1087959) on Tuesday September 17, 2013 @11:02AM (#44873771)

    Sitting in the left lane going ten under the speed limit while the world screams by.

    • by Valdrax (32670)

      Seniors see the world at blazing speeds... [s]itting in the left lane going ten under the speed limit while the world screams by.

      Well sure. Everyone knows that children grow at an impressive rate. By the time they reach 18, they are twice as large as they were at age 2. Extrapolating from that, by the time they are in their late 60s, the average senior citizen is nearly 50 feet tall and thus perceives the world at a fraction of the rate we young people do. You can see it best in how slowly they change their opinions. From their lofty perspective, nothing has changed.

      • You must know some really tiny 18-year-olds or some really big 2-year-olds! Most people I know are much more than twice as large as a 2-year-old when they become an adult.

        Unless you mean brain size, in which case I think you're being generous to many adults.
        • by dpilot (134227) on Tuesday September 17, 2013 @11:36AM (#44874223) Homepage Journal

          Actually no. He's quoting the "pediatrician's rule of thumb", approximately.

          Final height as an adult can be guessed by doubling a boy's height at 2 years, or a girls height at 18 months. Worked pretty well for both of my kids. (one of each)

        • by nedlohs (1335013)

          I think you might live in a world of very large adults or very small children in fact.

          Given the extrapolation given was for height, height is what is being talked about. And the average two year old in the US is a little over half the height of the average 18 year old (here's one reference: http://www.cdc.gov/nchs/data/nhsr/nhsr010.pdf [cdc.gov]).

          If you mean weight, then sure, but then the extrapolation makes no sense.

          • Fascinating! From my casual observations of men's height among subway riders, I figured about 1 in 20 guys were at least as tall as I am, and that table shows me right exactly at the 95% percentile! Science!

    • by omnichad (1198475)

      This is why it seems to take so long to turn off the left blinker.

    • by c0lo (1497653)

      Sitting in the left lane going ten under the speed limit while the world screams by.

      That's absolutely the fairest and most polite road behaviour in some parts of the world.

    • by mcgrew (92797) *

      I agree it's funny but it's actually backwards -- the older you get, the faster time goes. When I had six months left in the military it was forever. Now that I'm six months away from retirement, meh, six months ain't shit.

      I'm 61 and was talking about that with my Mom over the weekend. "Wait until you're my age!" she said. Hell, that's only 23 years, not long at all. Unless you are 23, in which case it's a lifetime.

      Even my 26 year old daughter has started noticing it.

    • by Solandri (704621) on Tuesday September 17, 2013 @12:29PM (#44875011)
      You joke, but I really think there is something to this.

      When I was in first or second grade (1970s), the U.S. was in the middle of its metric conversion program. We were taught the size of a cm vs an inch, the weight of a gram vs. an ounce, etc. I came up with some equivalencies on my own to help me remember everything. A cm was about the width of my thumb at the time. An inch was the length of of my folded middle finger. A foot was about the length of of my fist to my elbow... (Obviously none of these work anymore because I was a lot smaller back then.)

      Then we got to time. How long is a second? I tried counting "one one-thousand, two one-thousand" in my head like my teacher had suggested. It was too fast. I eventually came up with a "one (pause) and a two (pause) and a..." chant which (for me) accurately measured out each second.

      I'm in my 40s now and if I try my old timing chant, it's too slow. Each second I count takes nearly 2 seconds real-time. The "one one-thousand, two one-thousand" mnemonic now works for me. This also matches my memories of staring at the second hand on the clock in class, waiting for the time to pass so school would end. I watch a clock (with a second hand) today and it seems to move almost twice as fast as I remember it moving back then.

      My timing hasn't changed. I started playing piano in second grade. When I listen to old tape recordings of songs I still play, my tempo hasn't changed. The only explanation I can come up with is that my verbal and visual processing has slowed down with age. My piano playing has had the tempo reinforced every time I hear a recording of a piece, so it gradually (to my brain) sped up over the years to keep pace with my slower processing.
      • by rolfwind (528248)

        When I was in first or second grade (1970s), the U.S. was in the middle of its metric conversion program.

        Yeah, that really stuck.

        • by drinkypoo (153816)

          When I was in first or second grade (1970s), the U.S. was in the middle of its metric conversion program.

          Yeah, that really stuck.

          Oh, but it did. Now we use both SAE and metric measurements all over the nation.

    • And somehow that is dtill fsstrr the modt dwings of a fly dwatter.

  • From TFA:

    People have shown in humans that flicker fusion frequency is related to a person's subjective perception of time, and it changes with age. It's certainly faster in children.

    What about differences in physical size between members of the same species? I've heard "He's pretty quick for a big guy." But nobody ever says that of smaller people. Its just sort of a given.

    • Well, big guys have big levers to actuate too, so that's part of it. But I also read once that a brontosaurus would take 3 seconds to feel a poke on its tail.

      I find it sort of interesting that those B movie versions of Jack and the Beanstalk that show the slow, lumbering giants trying to squish Jack while he relatively darts around - were probably right.

      • Re:Within a species? (Score:4, Informative)

        by Oligonicella (659917) on Tuesday September 17, 2013 @11:39AM (#44874273)
        Correct. For those who don't believe this, go out in a field and catch a rabbit bare handed.

        As for the bronto, it's not really possible to know because we do not know what type of myelin sheathing they had on their nerves. It could be that their nerves propagated signals at 2mph (Iow end) or 200mph (highest). We don't know.

        If 2mph, a sixty foot animal's brain would get the signal in about three seconds, at 200 mph at .03sec. Or anywhere in between.

        Not really relevant though as the bronts had ganglia along their spines that did the reactions. Say the tail was 25 of that 60 and you have a little under a second low end perception time.
        • by mikael (484)

          Probably if you poked a Brontosaurus's tail, it would probably side-swipe the tail as a automatic reaction.

          • by Dr. Zim (21278)

            Did you mean autonomic reaction? http://en.wikipedia.org/wiki/Autonomic_nervous_system

      • by Russ1642 (1087959)

        You must have read that quite a long time ago as there is no species called a brontosaurus.

    • by Quirkz (1206400)

      I've heard "He's pretty quick for a big guy." But nobody ever says that of smaller people. Its just sort of a given.

      I've always wanted to work a number of reversed cliches into a story, with "He moved slowly for a thin man," being one of them.

  • Makes complete sense (Score:4, Interesting)

    by GodfatherofSoul (174979) on Tuesday September 17, 2013 @11:06AM (#44873831)

    I remember as a kid watching a sparrow fly through a chain link fence and thinking that kind of reaction time was impossible. Plus, when you look at the reaction time of smaller animals to a perceived threat (you trying to sneak up on one), we can't come close at our size.

    • by Ogive17 (691899) on Tuesday September 17, 2013 @11:08AM (#44873851)
      You haven't seen my reaction time when I spot a spider.
    • by Jason Levine (196982) on Tuesday September 17, 2013 @11:23AM (#44874047)

      I've thought of this too every time I try to swat a fly that found its way into my house. Flies seem to be able to do aerial maneuvers in reaction to threats that you would think impossible given their tiny brains. I often wondered if it wasn't that they were so quick, but that (to them) I was moving so slow. This might also explain why they seem to like buzzing right by me when I'm trying to kill them. They're taunting the big creature moving in slow motion. "You think you can catch me? I'm right in front of you. Nope. Now I'm over here. Over here. Over here. Too slow. Try and catch me." *zips into another room*

      • Re: (Score:3, Informative)

        by Anonymous Coward

        To kill flies (on a horizontal surface) with a high success rate, slowly move your hands near the fly so that your hands are about three inches above the surface and six inches apart. You should have the fly centered between your hands. That's the hard part-- getting into that position without spooking the fly.

        Now, as fast as you can, clap your hands once and leave them together. Usually the fly will fly straight up between your hands. Unfortunately, killing the fly may require some mashing your hands aroun

        • by Reziac (43301) *

          Or rather, slightly behind the fly, since most of 'em seem to take off backwards. (When I'm in practice, I get 'em on about half the attempts.)

      • I've thought of this too every time I try to swat a fly that found its way into my house. Flies seem to be able to do aerial maneuvers in reaction to threats that you would think impossible given their tiny brains. I often wondered if it wasn't that they were so quick, but that (to them) I was moving so slow. This might also explain why they seem to like buzzing right by me when I'm trying to kill them. They're taunting the big creature moving in slow motion. "You think you can catch me? I'm right in front of you. Nope. Now I'm over here. Over here. Over here. Too slow. Try and catch me." *zips into another room*

        Funny, I have no problem catching flies, even the tiny fruit flies. Perhaps it comes with all of that practice swatting mosquitoes and deer flies as a kid. Now, catching a fly with chop-sticks (Karate Kid) is an entirely different thing. I can't even catch food with chop-sticks unless I sharpen the ends with a pocket knife... (grin)

      • I've thought of this too every time I try to swat a fly that found its way into my house. Flies seem to be able to do aerial maneuvers in reaction to threats that you would think impossible given their tiny brains.

        I thought it was because your hand creates a big buffer of air in front of it, like a bow wave. The fly is so small, it's easily buffeted ahead and aside, so any manoeuvring gets it out of the line of your hand. Even easier when your hand approaches a hard surface - then the air squishes out to the sides, and the fly goes out with it. This is probably easier to visualize in a body of water - float a cork or a small piece of plastic in your sink, put your hand in the water, then try to squish the item up

        • by matfud (464184)

          Try slapping them from behind. They can still see you and react in the same way but can not get out of the way fast enough.

          • by Agent0013 (828350)
            That's because when they take off they jump backwards. I use a grabbing motion coming up from behind the fly. My hand being 2 or 3 inches above the surface. The fly jump up to take off and quite often ends up in my fist. Trying to squish them can be tricky so a lot of time I just throw them at a hard surface to stun them and then finish them off afterwards.
            • by causality (777677)

              That's because when they take off they jump backwards. I use a grabbing motion coming up from behind the fly. My hand being 2 or 3 inches above the surface. The fly jump up to take off and quite often ends up in my fist. Trying to squish them can be tricky so a lot of time I just throw them at a hard surface to stun them and then finish them off afterwards.

              The very best method to kill flies I have found is with a spray bottle of some kind of glass and surface cleaner. Something like Windex will work, or something stronger with chlorine/bleach will kill them faster. It's better to use the kind of bottle that lets you adjust the output from spray to stream. Stream is more effective but the mist will work if you get close enough. Give it a few practice squirts and you can easily refine your aim (if you ever do any target practice, this will be trivial). Nai

        • by mikael (484)

          Flies have some sensory hairs on the back that pick up any sudden changes in air movement. Some actually have a three individual compound eye facets to pick up sudden changes in light. Got to admire the design or the evolution. Mosquitoes do the same thing using one of their legs. The only way I can squish one is to throw a cushion at it.

        • by pnutjam (523990)
          Fly Swatters also have a lever effect which is probably the most effective part of them. The holes my help slightly. For every inch you turn your hand the end of the fly swatter moves several inches, thus amplifying your speed.
      • by mikael (484)

        The trick is that flies don't think about flying like the way a human would fly a plane - they react by something called "optic flow". Basically flight control is governed directly by the relative motion of different areas of their visual field and the resulting neuron activity. Moving straight ahead causes all objects to move away from the centre of vision. Moving backwards, causes objects to move towards the centre of vision. Turning will cause a couple of areas to remain static while others move rapidly.

        • by MiniMike (234881)

          Reaction to threats is simply "if a shadow rapidly gets larger then fly away towards a bright patch of light."

          So that's what I've been doing wrong. Next time I have to swat a fly I'll use a flashlight.

        • by matfud (464184)

          Sort of. The compound eyes never seem to produce an image. Not really enough neural matter there. Most reactions are based on differentials within the eye and between eyes. Finding food does not appear to be a function of the eyes (in flies). In bees it does to a small extent but more so the navigation mechanisms they use. Similar with ants. They follow the trails of scouts to find food. The scouts seem to wander almost randomly.

          • by matfud (464184)

            Interesting to note that arachnids primary eyes are not compound. Some even show planning ability when shown a sceen.

            • by chihowa (366380)

              Some of the most interesting spiders to interact with are the jumping spiders [wikipedia.org]. They'll spot you across the room and track you as you move toward them, turning their body to face you the entire time. They seem to keep a 3D map of the world around them, as well, as evidenced by their resistance to being herded into a jar behind them if they saw you put it there. Fascinating stuff!

              • by matfud (464184)

                And they are cute.
                Spiders cannot move thier eyes so move thier bodies, it is quite obvious when they are looking at you. The retina is relativly small for the size of the eye. However they can move the retina and they seem to scan the world by moving it around.

                A number of years ago I saw a film of a jumping spider trying to attack another spider (in a web). after a number of approaches failed the jumping spider dissapeared from the shot only to apear a while later on a twig above and offset wrt the web. Let

    • by dpilot (134227)

      Think about this for a moment from an evolutionary point of view. It make sense for the sampling rate of your brain to be geared to your body size - really to your ability to make your body move. In essence, if you could think/sample faster it usually wouldn't matter because you normally couldn't translate those faster thoughts into appropriate actions. Then add the fact that the brain is the densest user of energy in the body. To speed your thinking/sampling rate would likely mean burning more energy,

      • by matfud (464184)

        Humans have a distributed nerous processing system to help with signal speed issues. If you burn your finger your arm will move before the signal has a chance to reach your noggin let alone be processed and interpreted by it. Sample rate is the wrong term. response time is better but still not a great term. Whatever you call it it is variable and at different speeds within a single entity (depending on what the input is). Human stereo hearing is another example. Cross talk between the singnals from your ear

        • by dpilot (134227)

          Agreed, I was just using his term. Even though as you say, reflex actions don't get back to the brain before being processed, they still travel further in bigger organisms. I suspect nerve propagation rate is relatively constant, so of course bigger organisms will be able to sense and move more slowly. Roughly speaking, of course. As you say, we have phase response between our ears, and that's not slow, but the ears are relatively close.

          I guess my other point was where thinking is involved, we don't (or

        • by chihowa (366380)

          Human sound localization doesn't depend on response time as much as it depends on predictable timing between the two auditory inputs.The two inputs are compared to each other and the processing isn't especially fast (like the burned finger is fast). Sound localization mostly depends on a massive amount of differential spectral analysis, though. You can get a huge amount of information by the resonance of outer ear structures and the attenuation of certain frequencies by body parts.

          • by matfud (464184)

            I know. I was using it as an example of how sample rate is the wrong term. The timing differences between signals for each ear are significantly smaller than signal propagation time. However clever differetial processing can handle such small timescales. Yeh it will take you a while to determine the source of the sound as it is a higher level function but the raw signals (as in nerve signals (frequency pulses)) are handled at a much finer granulatrity than would be expected if you just looked at the 'specif

    • by Skapare (16644)

      My nephew, when he was a kid, chased down and caught a chipmunk [wikipedia.org] with his bare hands. I'd never seen him move so fast. I doubt he can do that now.

  • by Rick Zeman (15628) on Tuesday September 17, 2013 @11:07AM (#44873833)

    ....I can't swat the damn things. They have an unfair advantage!

  • by Anonymous Coward on Tuesday September 17, 2013 @11:09AM (#44873869)

    You practically have to be on meth to catch one. And then the problem is with the spiders in the corners of your eyes.

    • by steelfood (895457)

      And then the problem is with the spiders in the corners of your eyes.

      I don't want to burst your bubble or anything, but chances are, it's the spiders who're catching the flies. Just ask the old lady.

  • Who would ever have thunk it. Time of flight of a signal is dependent on distance.
    Next they will tell me that ping times are smaller for nearer nodes and I will be astounded and mystified.
    I am looking forward to overclocking flies for super slo-mo, however.
  • I read that as 'FILES'

  • Higher sample rate = more samples per second ~ more frames per second = slow motion. Shorter nerve lengths as well...
  • So an omnipresent being (everywhere, the size of everything), should have a time scale which relative to ours approaches zero.
  • Hey, don't judge...it was my week to chaperone the pre-teen girls on movie night.

  • by tippe (1136385) on Tuesday September 17, 2013 @11:46AM (#44874373)

    Funny timing. I just had a "movie night" on Saturday with my kids and saw "Epic" for the first time, whose premise is based on this idea (insects and small things which live in slo-mo world, or rather, that they see themselves as moving normally while they see us "big people" as large, slow moving, bumbling idiots).

  • ... at least I am convinced of that every time I try to sneak up on one and kill it...

  • by wonkey_monkey (2592601) on Tuesday September 17, 2013 @12:03PM (#44874607) Homepage
    I honestly though this was common knowledge already. Maybe I'm a little slow.
    • by NIK282000 (737852)

      They have a very specialized and very simple set of hardware and software that only has to do a few jobs, flying, eating etc. so they can devote all their processing time to doing those few things and they do them one at a time. Bigger, more complex animals have a lot of extra stuff taking up their brain time, social behaviour, non-automatic body maintenance or hunting, all of which are far more complex tasks then a fly while it flies. If you sit and watch one you will notice that flies act like really poor

    • I honestly though this was common knowledge already. Maybe I'm a little slow.

      Yes, I distinctly remember a scene from a documentary which portrayed a fly escaping being swatted by a rolled-up newspaper -- in super-slow-motion, to indicate that this was actually how the fly perceived the incident. I watched it in the early nineties.

      It might have been the "Time" episode of a href="http://en.wikipedia.org/wiki/Supersense">the series Supersense , although I'm not entirely sure. It was a brilliant series in any case.

    • Found it! [documentaryz.com] :)

      (The documentary referenced in my sibling post, that is. It's from 1988.)

      The fly-swatting scene is in the second-to-last episode on that page, from about 20:30.

  • ... when I was a kid wondering how flies could so easily see the fly swatter or my hand approaching. My guess was that since their brain was smaller, signals didn't have so far to go, and could be processed faster ... and they would see the world from this faster-brain perspective as a slow world.

  • Fly neurons aren't terribly different from ours. There are just fewer of them, doing less sophisticated processing. So the amount of processing that is done can happen in less time. In other news, Gedit is smaller and faster (at simple text editing) than Libre Office.

    This is one of those situations where the intuitively obvious is now scientifically established in a way that it wasn't before, I guess. But that's important, because a lot of intuitively obvious things are wrong, so they all have to be tes

    • by tippe (1136385)

      Your comment reminds me of a novel called Blindsight [rifters.com] by Peter Watts about an alien species that threatens Earth and humanity despite not having any individual or group consciousness. The author makes a claim that our consciousness slows us down and puts us at a severe disadvantage compared to other species (like the aliens) which can think much faster than us because they don't have an additional processing layer of consciousness to slow them down. I thought it was a really good book, and worth reading in

  • While size would matter, I don't see why metabolic rate should have anything to do with it. It's also funny to hear it described as 'time going slower.'

    The nervous system pathways for flies are much shorter. Therefore, flies have lower lag. Go figure.

    Just like an L2 cache on a computer processor, since the speed of information travel is pretty well fixed for the selected technology, using shorter path lengths yields faster response times provided the tasks are simple enough to benefit from it. Reflexes in p

  • It makes total sense. Think of it like shrinking a processor die - by bringing the transistors closer together you decrease the distance the signal needs to travel to be processed. Compare the size of a human brain to a fly's brain; 100,000 neurons and 10 million synapses that are packed into a space smaller than 1 mm^3 vs. a human's 87 billion neurons and 10^15 synapses for the entire nervous system, with the brain alone comprising 1250 cm^3 of volume.

  • by Skiron (735617) on Tuesday September 17, 2013 @12:43PM (#44875181) Homepage
    I always remember a science teacher telling us about this at school (what year, I can't remember, but I left school in 1976), and his statement was; "If a fly watched a film, it would see a still frame for a few seconds, then the next frame etc., as time moves more slowly the smaller the animal".
    • He didn't know that was true. He was just pulling shit from his ass. The fact that 40 years later he was proved right proves nothing, other than the fact that you remembered it.
    • by amaurea (2900163) on Tuesday September 17, 2013 @04:09PM (#44877669) Homepage

      I skimmed through the paper itself, and it seems like flies are only mentioned in passing. The paper mainly concerns itself with vertebrates, and their new result is that they have tested the hypothesis that smallness of body and high metabolism correlate with the flicker fusion frequency of the visual system, i.e. how fast a light has to flash before the flashing becomes invisible. They find the hypothesis to hold (like your teacher suspected).

      The fact that flies have a very high flicker fusion frequency (270 Hz vs. 60 for humans under ideal lighting), has, however, been known for a long time, and is not a new result from this paper. In fact, houseflies have 2.5 times higher flicker fusion frequency than even the smallest and most active vertebrates tested in this study (actually, looking at their graphs, it seems like the housefly would be a huge outlier if they had included it).

      The flicker fusion frequency is related to, but not the same thing, as how often an image needs to change in order to be percieved as motion. This difference is why 50-60 Hz CRT screens are annoyingly flashy to many, while 25 fps movies look fine. In the latter case, each image only changes slightly.

      For a fly, watching a 25 fps movie would probably be similar to watching an 8 fps movie for a human.

      • If i remember correctly, Octopus have an extremely high flicker fusion frequency as well. (heck, I think I learned that from a /. article ages ago)
  • I wondered about this 30 years ago. It's more an issue of mass than anything else. You can move faster, so your brain operates more quickly to compensate. Whales and elephants even slower.

    I would hypothesize an elephant brain in a vat tied in to a mouse body would speed up accordingly, and it would be less related to brain size (and intra-neural distances) than what it has to accomplish.

    Similarly a human mind in a virtual world might speed up if the world's physics were sped up AKA had lowered mass relat

  • This is probably why you can cup a fly with your hand if you do it slowly enough; any motion that seems slow to us will be imperceptible to the insect. It also makes it impossible for the fly to sense the air displacement.
  • very cool to see more empirical work on this!

    I used the basic resonance model to figure this out for humans.. seems to work well:

        https://sites.google.com/site/pablomayrgundter/mind [google.com]

    Cheers,
    Pablo

  • by Bootsy (33005)

    Flies See the World In Slo-Mo? To them it passes at regular speed, we are just slow moving creatures to them. Watch an elephant. Or better if possible a big dinosaur. Do we see the world moving in Slo-Mo because we aren't the size of a dinosaur? It's only a perspective thing, every creature has the perspective of life moving at the "regular" speed of course.

  • Now what happens when we take it to the other extreme? What about a massive life form the size of a planet, or a solar system? How would it perceive time? Its metabolic rate would by necessity be much slower than ours, so would most likely perceive time in very fast motion and, if the life cycle was anything like ours, could have a lifespan of millions of years.

    Not terribly exciting, perhaps, until you consider this:

    The speed of light in a vacuum is fixed in any given reference frame, and measured in dis

    • by Reziac (43301) *

      "What about a massive life form the size of a planet, or a solar system? How would it perceive time? Its metabolic rate would by necessity be much slower than ours, so would most likely perceive time in very fast motion and, if the life cycle was anything like ours, could have a lifespan of millions of years."

      Or maybe not; its metabolic rate might be much faster, and perceived by us as a 'sun'.

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