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New Theory on Water Strider Propulsion

capt.Hij writes "There is an interesting article at the Christian Science Monitor about how water skimmers are able to move the way they do. This new theory debunks the previously accepted theory and answers why smaller, younger water skimmers are also able to move the same way as their elders: 'As he looked into the question, he adds, he learned that the reigning explanation leaves an unsolved puzzle: If these tiny insects propel themselves in the way many researchers think they do, then baby water striders should go nowhere fast.'" There's also a BBC story with pictures.

25 of 204 comments (clear)

  1. Dancing legs by Jarlsberg · · Score: 5, Informative

    They move by using their mid leg pair as oars and the back pair as steering wheels. Previously, researchers thought they generated small waves, but baby water striders are too small to generate waves big enough to move on. The new research show that the waves are a biproduct of using the middle pair as oars, not the reason they move. Pictures here, same news in norwegian here.

  2. Article is in Sci-Am by madaxe42 · · Score: 3, Informative

    Very good article on this in scientific american, if anyone is interested!

    1. Re:Article is in Sci-Am by LucidBeast · · Score: 3, Funny

      I assume that Sci-Am doesn't explain how Jesus was able to walk AND propel himself on water.

  3. A related article (as seen on Fark) by sczimme · · Score: 4, Informative


    The Independent has a related article here.

    --
    I want to drag this out as long as possible. Bring me my protractor.
  4. Sculling... by LouisvilleDebugger · · Score: 5, Informative

    My mother was raised literally on the river (towboat pilot Dad), and knows how to "scull" (propel a small boat from the stern using a single oar or paddle.) The oar stays in the water and does describe a circular or elliptical path. It's about the weirdest means of locomotion I've ever seen, and doesn't look like it should work. But I can vouch that it does.

    I could never do it, although I was just a kid the last time I tried. Anyone here who can?

  5. Duh... by jeffkjo1 · · Score: 5, Funny

    Everybody whose anybody knows waterstriders use anti-matter as propulsion.

  6. A challenge by D0wnsp0ut · · Score: 5, Funny

    All I know about water skimmers/skippers is they're a bugger to hit with rocks, unless you get a really big, flat rock and even then you mostly just get yourself wet and still miss the skimmer.

    --
    "Those who would sacrifice liberty for security deserve neither!"
  7. Don't need to read it. by rde · · Score: 3, Funny

    a) It's in Christian Science Monitor
    b) It's about skimming over the water.

    Chances are, Jesus features in the answer.

    1. Re:Don't need to read it. by The+Ape+With+No+Name · · Score: 4, Insightful

      Ummm. CSM is about as good as a balanced source as you will find and, despite the name, they don't do ridiculous things like you are talking about. My local rag will probably run this on the Religion section this week rather than the Science page. You should know better. Kind of like Brit "Goebbels" Hume, questioning the source of an eyewitness account of American soldiers abusing Iraqi citizens, by saying, "What do we know about this paper The Manchester Guardian?" rather than saying, "Secondary sources have yet to confirm or deny the report from the Guardian.

      --
      Comparing it to Windows will be a moot point, since El Dorado is going to have a 40% larger code base than XP.
  8. Amazing by Vexalith · · Score: 5, Insightful

    I think it's an interesting reflection on humanity when evolution can throw up designs that we can't properly understand even with all of our apparent science and technology (bees, water striders, the thought process). It just goes to show that for every fact or theory we think we know there are far more that we don't, which gives me great confidence in the progress of human science and technology over the next few thousand years.

  9. Wrong. by Anonymous Coward · · Score: 4, Funny

    They move because they put their faith in jesus and he spirits them along over the water on the wings of christ.

    Damn dude, it said the CHRISTIAN science monitor.

    You remember.. the people who don't believe in evolution? Or stem cell research? Or cloning?

    1. Re:Wrong. by RobinH · · Score: 4, Interesting

      They move because they put their faith in jesus and he spirits them along over the water on the wings of christ.

      Damn dude, it said the CHRISTIAN science monitor.

      You remember.. the people who don't believe in evolution? Or stem cell research? Or cloning?


      That would certainly be most people's first impression, but I find that the CSM is probably the *most* objective reporting I've ever seen to date. There doesn't seem to be any particular bias that I can see. I'm glad I found the CSM, and I really enjoy reading it, even though I'm agnostic. I highly recommend everyone take a look with an open mind.

      --
      "I have never let my schooling interfere with my education." - Mark Twain
    2. Re:Wrong. by revery · · Score: 4, Funny

      You remember.. the people who don't believe in evolution? Or stem cell research? Or cloning?

      Yeah, those three are the same.

      Do you mean that they don't believe cloning is possible, or that they don't believe evolution is moral?

      --

      I don't believe in you...

    3. Re:Wrong. by Gzip+Christ · · Score: 5, Funny
      That would certainly be most people's first impression, but I find that the CSM is probably the *most* objective reporting I've ever seen to date. There doesn't seem to be any particular bias that I can see. I'm glad I found the CSM, and I really enjoy reading it, even though I'm agnostic. I highly recommend everyone take a look with an open mind.
      I second that. Compared with the mainstream press, it's utterly amazing how objective the Monitor has been throughout the whole water spider controversy.
    4. Re:Wrong. by overunderunderdone · · Score: 5, Informative

      I think you may be misunderstanding where the name "Christian Science Monitor" is coming from. This is NOT a journal of science put out by Christians (creationist or otherwise) The CSM is a paper that was founded by a religous group founded in the 1800's known as the "Christian Scientists" or more formally "The Church of Christ, Scientist". The group is often considered a cult and is pretty much disavowed by both christians and scientists (and presumably christian scientists that are not "Christian Scientists"). From time to time they get in the papers because at the core of their beliefs is faith healing, or more accurately that there really is no such thing sickness anyway, so they will refuse medical treatment for themselves and their children.

      The Christian Science Monitor itself is a highly respected paper and while I think it is still officially owned by the church I think they have a hands off approach to running it and if they are using it for "evangelistic" purposes they use it by putting out a very high quality paper that by it's quality lends credibility to their group rather than using it as a polemic tool in itself. It's seems it's sort of like the Moonies owning the Washington Times rather than like an official organ of the church.

    5. Re:Wrong. by JonathanBoyd · · Score: 4, Insightful

      If you can have miracles, that doesn't mean that you can't apply science the rest of the time. The two aren't incompatible.

  10. Now that... by Akardam · · Score: 3, Funny

    ... is a bug!

    1. Re:Now that... by borgboy · · Score: 4, Funny

      Nope. It's a feature!

      --
      meh.
  11. Surface tension is cool! by PhysicsExpert · · Score: 3, Interesting

    A few of my colleagues have been looking into the effects of surface tension in various liquids and you'll be amazed to learn what you can do if you have the right circumstances.

    H20 doesn't have that much surface tension becuase of its low valency, but other liquids such as bromine are held together by strong Van der Waals attractions meaning that they have much stronger surface tensions. In one famous experiment at MIT researches showed just how strong the surface tension could be by placing a cat onto a large pool of bromine and observing that not only did it not sink but that it could also move abount (albeit with difficulty). Some people have suggested (tongue in cheek) that if Jesus could have introduced bromine into the red sea then that would explain how he could have walked on water.

    --
    All that glitters has a high refractive index.
  12. Impressionist Insects by unfortunateson · · Score: 3, Interesting

    Go take a gander at the original BBC article with the photos. The one with the blue dye in the water showing the eddies created by the movement is practically a natural reproduction of Van Gogh's brushwork!

    It's like having insects do impressionist painting. Truly beautiful. If I can find a high-res photo, I think I've got my new wallpaper.

    --
    Design for Use, not Construction!
  13. Oh my... by tkittel · · Score: 5, Funny

    It seems that we have a Christian source of information related to walking on water?

    At least it is their own IP :-)

  14. Matthew 14, 25 by godot42a · · Score: 3, Funny

    It's not the Red Sea, it's the Lake of Gennesaret.

    The Rea Sea was the one where the surface tension didn't hold up to the weight of the Egyptian Army ;)

    Just my E0.02.

  15. Re:Surface tension is cool! - Troll Alert!!! by pdp11e · · Score: 5, Informative

    Now this is a troll if I ever saw one. Bromine is the only liquid nonmetallic element. It is a heavy, mobile, reddish-brown liquid, volatilizing readily at room temperature. It is toxic comparable to chlorine. The surface tension of bromine is LESS then that of the water.
    Cat (or any other live being) in a large pool of bromine has a life expectancy of a few minutes. And yes it would sink.

  16. Dr. Bush by fruity1983 · · Score: 3, Funny

    "Doctor" and "Bush". After the last few years, I have a lot of trouble visualizing that...

    --
    I am a viral sig. Please copy me and help me spread. Thank you.
  17. Re:Water Tension by srw · · Score: 4, Funny

    > Now all we need is to figure out how to make water have enough tension to hold a person. Hrmm...

    Simple. This happens naturally where I live. I simply have to wait until, say, mid-November. The surface tension remains high until some time in spring. It only works for water kept outside or in an unheated building.

    -srw