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"Ballooning" Spiders Use Electrostatic Forces To Generate Lift 213

Posted by samzenpus
from the when-spiders-learn-to-fly dept.
KentuckyFC writes "Many types of small spider release threads into the air which then lift and carry them significant distances. Biologists have found them at altitudes of up to 4 km. The conventional thinking is that the threads catch thermal air currents which then carry them away but this does not explain how spiders perform their trick even when there is little or no wind. Now one physicist says the explanation is the atmosphere's natural electric field which has an average downward-pointing magnitude of 120 Volts per metre. He calculates that a strand of silk need only gain a negative charge of around 30 nanoCoulombs to lift a spider. That explains how the spiders take off on windless days, how they reach such great heights and how several strands can lift heavier spiders of up to 100 milligrams."
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"Ballooning" Spiders Use Electrostatic Forces To Generate Lift

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  • Does this explain how Spider-Man can shoot and then swing on webs that are attached to... what? Clouds? The International Space Station?
  • by schneidafunk (795759) on Monday September 23, 2013 @10:33AM (#44923823)

    "Of course, Gorham’s ideas will need to be tested by actually measuring the charge on gossamer spider silk as it is generated. That’s an experiment for an enterprising biologist to take on."

    • by goombah99 (560566) on Monday September 23, 2013 @01:06PM (#44925473)

      I will have to read the research article because the press article doesn't explain it. a dipole charge would not move in a linear gradient field. it would require a second order curvature to the gradient to make it move. thus it's irrelevant that the linear field is 120 v /meter. what would matter is the derivative on that.

      • Just a thought, could Archimedes Law apply here, but instead of water, the medium is the ambiant air?
        • Air is fluid so, yes, Archimede's law is if application too.

        • by TeknoHog (164938)

          Just a thought, could Archimedes Law apply here, but instead of water, the medium is the ambiant air?

          That is exactly how hot-air and helium balloons, blimps etc. work. It is left as an exercise to the student to work out why that would not work with a spider and/or its thread.

    • Of course, Gorhamâ(TM)s ideas will need to be tested by actually measuring the charge on gossamer spider silk as it is generated.

      Rather than trying to test it directly, just modulate the field in a room containing such a spider.

      If the spider and its silk has a net charge you should be able to steer it around the room, land it where you want it, and measure the charge by the spider's response to the ambient field you're modulating. The attitude of the spider/silk system in the modified field will also

  • Yes (Score:4, Insightful)

    by Flipstylee (1932884) on Monday September 23, 2013 @10:34AM (#44923837)
    Stories like this are the reason i frequent /.
  • by gestalt_n_pepper (991155) on Monday September 23, 2013 @10:35AM (#44923841)

    This really bugs me.

    • Imagine a surveillance drone that's levitated by its own antenna :)
      • by wagnerrp (1305589)
        Now all you have to do is figure out how to fit a usable amount of sensors, communications gear, and power generation in something that weighs on the order of a few hundred milligrams.
      • by Nrrqshrr (1879148)
        Am still shocked at this part... "Biologists have found them at altitudes of up to 4 km"
        Do you realize what this implies? One day a spider got bored and he decided to see how high he could fly... and he went 4 fucking kilometers in the sky...
        • by Plunky (929104)

          Am still shocked at this part... "Biologists have found them at altitudes of up to 4 km"

          Well, life gets around it seems. Perhaps you would be interested to hear that I have seen small flying insects several hundred miles out at sea (that didn't seem desperate to land, on my small yacht).. also crabs out there, swimming on the surface, and the water was 2-3 miles deep. I don't know how they get there; presumably they don't swim up from the bottom.

          • by cusco (717999)

            When Krakatoa blew up and humans were finally able to visit the shattered remains of the island the only living thing they saw was a spider in a web, apparently newly arrived.

        • Do YOU realize what this means? Apparently there are biologists at 4 km altitude!
  • Nature is amazing (Score:5, Insightful)

    by brunes69 (86786) <slashdot&keirstead,org> on Monday September 23, 2013 @10:41AM (#44923873) Homepage

    To me stuff like this is what proves evolution. There is no one in their right mind who could sit there and convince me that such an obtuse solution to move from point A to point B is "by design", vs. random evolution.

    • by jones_supa (887896) on Monday September 23, 2013 @10:50AM (#44923931)
      I sometimes tend to think the opposite: some of the evolution's achievements seem so precisely engineered that it feels more like a designer's product than test of time. Not that I would actually believe in intelligent design and all that stuff.
      • by MadKeithV (102058) on Monday September 23, 2013 @10:53AM (#44923957)

        I sometimes tend to think the opposite: some of the evolution's achievements seem so precisely engineered that it feels more like a designer's product than test of time. Not that I would actually believe in intelligent design and all that stuff.

        Most "precisely engineered" stuff that's actually engineered is still the product of large quantities of trial and error, at some level :)

      • by Darinbob (1142669)

        Hasn't anyone considered te in-between theory? That of unintelligent design? As in these spiders were just the intern's first attempts at a design but then accidentally got loose onto creation?

    • by hort_wort (1401963) on Monday September 23, 2013 @11:25AM (#44924245)

      What if the intelligent designer just wanted to use evolution? I've never understood why the two solutions have to be exclusive.

      • Then he becomes a god of the gaps.

      • by brunes69 (86786)

        Then he isn't very intelligent, is he?

        That is like saying "why would you use math to figure out the area of that rectangle when you can just guess randomly until you find a fitting number". Both solutions work but one is intelligent.

        • That is like saying "why would you use math to figure out the area of that rectangle when you can just guess randomly until you find a fitting number". Both solutions work but one is intelligent.

          Scientists use the Monte Carlo method all the time. Depends on the experiment.

        • > That is like saying "why would you use math to figure out the area of that rectangle when you can just guess randomly until you find a fitting number".
          > Both solutions work but one is intelligent.

          That's the same distinction between an old-school program that tells the machine exact instructions "go forward 3 meters, turn left, go 1 meter", vs. artificial intelligence - building a robot that can adapt to it's environment. Why make it adaptable when you can program in precise instructions to begin wi

        • I've always thought about it more like a Chemist or nanotechnologist. You don't get a really small pair of tweezers and put molecules next to each other to make them react, you just pour stuff into a beaker with the knowledge of what will happen on scales too small to really control. God put a bunch of matter into a void with the knowledge that it would expand and become a universe, and in that universe intelligent life would emerge.

      • Because 'intelligent design' was never a real theory. It was a legal dodge. An attempt to say 'God poofed everything into existence' without actually sounding religious.

      • What if the FSM just wanted to use gravity as an extension of his noodle-down-pushing-power?

        It's a meaningless statement. If god created all the multitude of animals through the use of evolution, how is that any different from just... evolution? Why add the extra assumptions in there if they don't contribute to the theory? I'm not saying the statement is wrong necessarily, just that it's meaningless; the two parts of the statement belong to two fundamentally different philosophies.

        • Why add the extra assumptions in there if they don't contribute to the theory?

          That's exactly what I'm thinking. Excluding possibilities adds assumptions to the theory as well. Evolution doesn't need a statement concerning the FSM either way.

      • I've never understood why the two solutions have to be exclusive.

        They don't have to be. It's just that evolution has an extensive and rigorous body of evidence, while intelligent design has nothing but wishful thinking and hand-waving.

        They don't have to be mutually exclusive. It's just that in practice, they are.

    • by tobiasly (524456) on Monday September 23, 2013 @11:40AM (#44924411) Homepage

      To me stuff like this is what proves evolution. There is no one in their right mind who could sit there and convince me that such an obtuse solution to move from point A to point B is "by design", vs. random evolution.

      As a scientist who happens to also believe in a creator, I don't understand why evolution and intelligent design have to be mutually exclusive. Why can't a creator have designed evolution?

      The fact that life on this planet has undergone -- and continues to undergo -- evolution is undeniable. That doesn't prove that God doesn't exist. A system that is not only capable of propagating itself indefinitely but also continually updates itself over centuries and millennia.. now that's a pretty impressive hack if you ask me.

      A common refrain from those who want to disprove intelligent design is "this creature's adapted behavior isn't the most efficient way to accomplish this task, so therefore it was not designed by an all-knowing, all-powerful creator". Just because this spider's means of locomotion is an "obtuse solution" also doesn't mean it's not "by design".

      Who says God doesn't have a bit of Rube Goldberg in him? You're presuming that he's trying to create the perfect organism and he just can't quite get it right. Maybe he realizes that if he created the perfect spider it'll freak the hell out of his humans who will then wipe it off the planet.

      • by brunes69 (86786)

        You're now trying to twist things around to fit into your concept of a creator.

        Saying there is an intelligent designer who uses evolution makes no sense, because the whole point of evolution is that it is random. As such, it's actually very inefficient.

        As I posted in another thread... this is like saying "why would you use math to figure out the amount of weight this can hold, when you can just guess randomly until you find a really big amount that it can hold". Both solutions work but one is intelligent an

        • by Lithdren (605362) on Monday September 23, 2013 @12:36PM (#44925111)

          I'm gonna preface this with the fact that I do not believe in a god or gods of any sort. But your disagreement with his opinion is sorta silly.

          Look, Evolution is fact. The Theory of Evolution is still open to debate, how it works, what impacts it, etc.

          His opinion on it seems to be that a creator could design something like a self-serving system to improve over time. Your argument is "Thats not efficent". Who says it needs to be? If God really did exist, who says he cares how much time it takes? Who says they/it would even expierence 'time'?

          In the tend, religion and things like 'intelegant design' are little more that faith based beliefs trying to take what science has shown to be true and make sense within their own religious construct. There's nothing wrong with this, even if it's not right. You're doing it right now through your senses. You're not seeing white background and black text, you're interpreting what your eyes are sensing as those colors and shapes.

          When you get down to it all you're seeing are waves of photons and a weird mish-mash of quarks and glueons. Trying to talk to someone about why their belief is wrong is like trying to explain to someone why a red apple isn't red. It wont change their world view, so stop trying. Just accept that some people see the apple as Red, while other people dont. Trying to argue against their point only lets them decide how the argument is played out, in their own terms and on their own grounds. If you dont believe, great. If you do, great.

          In the end, we're all wrong anyway, that much im certin of.

          • by Lithdren (605362)

            Wow, reviewing that I have more spelling errors than I care to admit to. Between being sick and being short on sleep...it shows.

      • by radtea (464814)

        Who says God doesn't have a bit of Rube Goldberg in him?

        Everyone who claims god both all-powerful is not an evil, sadistic, bastard.

        A god who could create this world without killing off the vast majority of every generation of every species of every living thing (except humans after we invented science and democracy and capitalism) yet did not do so is unequivocally evil by any sane standard of morality.

        A god who could not do so is not all-powerful.

        Evolution is the most vicious, inefficient, monstrously cruel mechanism for the creation of the diversity of life y

    • It's just the opposite for me. I see such elegant and ingenious solutions as this, the bacterial flagellum, geared insect legs, octopus cromatophores, etc., as evidence for a brilliant Creator God.
    • by beschra (1424727)

      I find that when faced with something like this, people almost invariably see what they bring into it, as evidenced by some of the comments. If you expect evolution, you see evolution. If you expect a designer, you see a designer. These kind of things don't persuade me either way, but I do find it to be *really* cool regardless of how it came about.

  • So why are we unable to tap the planets electric field? Can someone explain this a little more. Seems like that is a power source just waiting to be tapped. Unintented consequences like collapsing earths magnetic sphere aside.

    • I've just read that one bolt of lightning powers one household with all their energy needs for a month. I'm not too sure how accurate that is; but I think we'll need a lot more than that.
      • It might be worth setting up lightning rod power stations if there were a way to store it.

        • It might be worth setting up lots of $PowerStorageStations if there were ways to do that.

          If we had a reliable, scalable, generally applicable (ort two out of three) method of storing instantaneous power generation from a variety of natural or man made resources, wind and solar power would completely stomp fossil fuels for baseline power use.

          We don't and it doesn't. Yet.

      • by n7ytd (230708)

        One household for a month, or one trip anytime into the past or future with your hovering time machine!

      • by jones_supa (887896) on Monday September 23, 2013 @12:44PM (#44925215)

        I've just read that one bolt of lightning powers one household with all their energy needs for a month. I'm not too sure how accurate that is; but I think we'll need a lot more than that.

        I will try to plug the numbers in. Let's see how this goes.

        According to the physics.org toast power article [physics.org], a lightning packs "over five billion joules of energy". I will round that down to 5 billion. A watt is the same thing as "joules per second". A month has 60 * 60 * 24 * 30 = 2,592,000 seconds. Then, 5 * 10^9 J / 2,592,000 s = 1929 J/s. This means that we can run the house at a constant power consumption of 1929 watts. Converted to a standard kWh number that would be 1389kWh per month.

        That's pretty much on the spot. It would indeed be enough to run a house of a small family for one month, accounting electrical heating running around winter.

    • by necro81 (917438) on Monday September 23, 2013 @11:15AM (#44924135) Journal
      The earth's magnetic field is almost certainly unrelated. The magnetic field is generated internally due to us having a molten iron core. This atmospheric electrical field comes from the bulk transport, separation, and friction of huge air masses - like the kind that give rise to thunderstorms. There's interplay between the two, especially during a solar storm (e.g., aurorae), but you couldn't freeze the magnetic field by tapping the atmosphere.

      As for why we can't tap that, I could only speculate. 120 V/m sounds like a sizable field - strong enough that we ought to be able to feel it. On the other hand, the E-field in an ordinary capacitor is many orders of magnitude greater (10s of volts, perhaps, but separated by just microns). You can get a greater E-field from peeling scotch tape off its roll.

      Also bear in mind that an electric field, by itself, is not a store of energy. In order to make use of that field, you need to have charge traverse that field - a flow of electrons. If we think of the atmosphere between stratosphere and ground like a giant capacitor, its stored energy is 1/2 * C * V^2. The V term might be very large (120 kV/km, squared!), but if the C is tiny, then you end up without much energy. And do not conflate power and energy: you can get quite a spark from a discharging capacitor (or a lightning bolt!) - great instantaneous power - but it doesn't last. Unless there's some source to continuously replenish the charge separation, you may not be able to tap much energy. I suspect that the available energy is very diffuse; more diffuse than, say, the kinetic energy of wind that we are able to capture with turbines. You would probably need kilometer-sized antenna arrays to capture much useful power.
  • by b4upoo (166390)

    NSA and DOD will have a nervous breakdown trying to build a drone the size of a small spider that can make silk.

  • Do they know that they are using an electric field to generate lift?

  • So how long until I can use this technology to finally get my flaying car?

  • So how long until this technology can be used to build the flying car I've been promised for several decades?

  • Somehow the "Electric Spider" sounds like it's right out of an early 80's night club choreography.

    (yes, I know there was the Electric Slide, thank you)

  • by Muad'Dave (255648)

    30 nanoCoulumbs = 6.24 Biiiiilllion electrons.

    • Which would still be something along the lines of .000001% of the electrons in 1 meter of silk.

      Every now and them I'm reminded just how small atoms actually are.

    • by Muad'Dave (255648)

      Heck - make that 187.25 Biiiiilion electrons. I forgot to multiply by 30.

  • Can we duplicate this for a space elevator?

    The problem was always that hundred mile cable, can use an incomplete cable link to float to orbit?
  • The magnetic fields goes out of the atmosphere.. if the spider for some reason can't control its ascent, I'd guess it goes all the way up? Sounds like a new micro-satellite technology!

  • by TheSync (5291) on Monday September 23, 2013 @02:24PM (#44926319) Journal

    I'll believe this when someone takes some spider silk, charges it up, and it can lift an inanimate object of weight of a spider in still air.

  • by m6ack (922653) on Monday September 23, 2013 @03:49PM (#44927285)
    I wonder if the same concept could be used to help relieve stress on the cables of space elevators? How much charge would it take to offset the weight of some amount of cable and can solve a measure of the strain problem?

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