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Why Birds Fly In a V Formation

Posted by samzenpus on from the heading-south dept.

sciencehabit writes "Anyone watching the autumn sky knows that migrating birds fly in a V formation, but scientists have long debated why. A new study of ibises — where researchers took to microlight planes and recorded birds strapped with GPS in-flight — finds that these big-winged birds carefully position their wingtips and sync their flapping, presumably to catch the preceding bird's updraft and save energy during flight."

5 of 207 comments (clear)

  1. This is new? by Anonymous Coward · · Score: 5, Insightful

    I remember being taught this as a child in the 80s.

    1. Re:This is new? by Immerman · · Score: 4, Insightful

      >So, it's a little bit of a behavioral science study...is saving energy why they do it, or is saving energy just a happy consequence?

      That seems like a question that would be *extremely* hard to answer in any way except "of course they do it because it saves energy". Assume for the sake of argument that it can somehow be proven that each individual bird flies as it does simply because it "feels good", or any other reason. The question still remains *why* does it "feel good", with the answer almost certainly being that evolution, that old non-sentient intelligence, sculpted the species in favor of some random mutation that made a more energy-efficient behavior "feel good". If there hadn't been a survival benefit to the behavior then it's unlikely it would have spread throughout the entire population.

      It's like the adage says: "We don't like sugar because it's sweet, sugar is sweet because we like it". There's nothing inherently "sweet" about a sugar molecule, sweetness is a function of our brains interpretation of the signals from the chemo-receptors on our tongues. Sugar triggers a pleasure-response (sweetness) because our metabolisms can harness it as a rich energy source. Some distant ancestor who found sugar pleasurable consumed more energy rich fruits, and thus had more energy available and could out-compete their "sweet-less" rivals, and so the mutation spread throughout the population. Cats on the other hand are obligate carnivores whose metabolisms can't efficiently process sugars, and they lack the appropriate chemoreceptors to detect them - for them sugar is *not* sweet, and any mutation that changed that would rapidly fall out of the population because it would reduce the amount of fats and proteins consumed in favor of sugars that don't provide them much energy, making the afflicted individuals less competitive.

      Research into the actual *mechanism* of the energy savings is still interesting though, we are only just beginning to understand the subtleties of flexible-wing flight. Dragonflies for example actually appear to use their front wings specifically to generate vortices (generally considered energy-sapping flaws to be minimized in fixed-wing aircraft) rather than producing thrust - the rear wings then interact with those vortices in a manner that provides more thrust than they could hope to generate directly. *Extremely* sophisticated energy-optimizing behavior that makes our fanciest aerodynamics technologies look like dog-paddling in comparison.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
  2. Obvious and already known by Anonymous Coward · · Score: 0, Insightful

    What a waste of money.

  3. Old news...very old by Nethemas+the+Great · · Score: 3, Insightful

    This has long been the explanation of why birds fly in an echelon formation and why throughout a migration the front ranks cycle from the front to the rear. As the leading rank of birds tire, the next rank takes over allowing them a bit of a rest.

    --
    Two of my imaginary friends reproduced once ... with negative results.
  4. now, maybe, there's DATA not guesswork? by dltaylor · · Score: 5, Insightful

    Although this may not be the first time the airflow effects have been measured "in the wild", I cannot remember any previous instance.

    There are a lot of things "everybody knows" that have never been verified. It doesn't hurt to run the experiments and perform the verification.

    "Everybody knew" that time passed slower on a body moving faster; after all, Einstain had said so. Still, it wasn't until we put sufficiently accurate chronometers on spacecraft that we really knew it, because they did, in fact, show that the spacecraft experienced less time than the ground stations. Although surface installations are "orbiting" at about 1000 MPH (too easy with a 24 hour day and 24000 mile circumference), and are at the 1G level of the Earth's gravity well (also has an effect), the space craft are moving at about 16000 MPH (90 minute orbit at 100 mile AGL) and still at nearly the 1G level of the gravity well. That 15000 MPH difference shows up readily, even after the adjustment for gravity.