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"Ballooning" Spiders Use Electrostatic Forces To Generate Lift

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."

12 of 213 comments (clear)

  1. Next step is testing by schneidafunk · · Score: 5, Insightful

    "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."

    --
    Some people die at 25 and aren't buried until 75. -Benjamin Franklin
  2. Yes by Flipstylee · · Score: 4, Insightful

    Stories like this are the reason i frequent /.

  3. Nature is amazing by brunes69 · · Score: 4, Insightful

    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.

    1. Re:Nature is amazing by jones_supa · · Score: 4, Insightful

      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.

    2. Re:Nature is amazing by MadKeithV · · Score: 5, Insightful

      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 :)

    3. Re:Nature is amazing by hort_wort · · Score: 5, Insightful

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

    4. Re:Nature is amazing by tobiasly · · Score: 3, Insightful

      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.

    5. Re:Nature is amazing by RKThoadan · · Score: 5, Insightful

      "not as efficient?" These seem a whole lot more efficient than wings to me. A single one-time expenditure of energy and they go for miles. There are downsides to this method of course, most obviously that they don't have any control of where they go. But if you accept that limitation this seems to be a nearly optimal method of flight.

    6. Re:Nature is amazing by Lithdren · · Score: 3, Insightful

      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.

  4. not an effective strategy, seems bugs can't read by Thud457 · · Score: 3, Insightful

    The rule in my house is that if you have more than four limbs, you are a bug , and you belong outdoors. This policy is clearly stated on the signs underneath each door.

    --

    the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff

  5. Honestly it looks more to me like... by Anonymous Coward · · Score: 2, Insightful

    Life imitates glitching :)

    I mean this sounds exactly like some games that have double-jump and other glitches. Officially nothing is supposed to float unless it's lighter than air, but in reality there's about six (known) ways to exploit aspects of the world that were 'never intended' to end up with flight. Much like with videogame physics some animal figures out a trick, then keeps iterating until that trick is an art, then a science, and finally a way of life :)

  6. Show me an experiment by TheSync · · Score: 3, Insightful

    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.