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Communications Science

How Bird Flocks Resemble Liquid Helium 40

sciencehabit (1205606) writes "A flock of starlings flies as one, a spectacular display in which each bird flits about as if in a well-choreographed dance. Everyone seems to know exactly when and where to turn. Now, for the first time, researchers have measured how that knowledge moves through the flock—a behavior that mirrors certain quantum phenomena of liquid helium. Some of the more interesting findings: Tracking data showed that the message for a flock to turn started from a handful of birds and swept through the flock at a constant speed between 20 and 40 meters per second. That means that for a group of 400 birds, it takes just a little more than a half-second for the whole flock to turn."
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How Bird Flocks Resemble Liquid Helium

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  • by Artifakt ( 700173 ) on Monday July 28, 2014 @02:52AM (#47548069)

    One factor not mentioned in the summary, is that bad computer models for flocking can still generate what looks like realistic flocking behavior. The herd dinos in Jurrassic Park are an example of this - the animation formula assumed each dino was instantaniously aware of all the rest, without allowing time for their nervous systems to work, but the flocking motions still looked right to most people, including professionals. People should remember too, humans probably have some pretty good mechanisms built into their brains for analyzing flocking, so that our ancestors, going at least as far back as the ape-like ones, could successfully hunt birds in flocks, and we collectively and historically certainly have had a lot of practice at that. We, as a species, ought to have some skill at detecting what constitutes real flocking behavior, but if we do, it doesn't always make a bad formula look jarring or wrong. So when somebody claims they have a real formula for what's going on when birds and such flock, the next question is "Can this claim even be proven or disproven?"

    • Can this claim even be proven or disproven?

      Silly question on a nerd site, you don't "prove" anything with science, and Jurassic park was a movie, not a scientific model.

      Back then the short cut they took probably saved them weeks in rendering time, and as you say, came out looking realistic. A scientific simulation would be comparing real data points to the output, it would be able to identify the "handful of leaders" that initiate each manoeuvre of a real flock, it would definitely not be a bunch of lab coats looking at the pretty pictures and no

      • Back then the short cut they took probably saved them weeks in rendering time, and as you say, came out looking realistic.

        Why is that? There's no reason that I can think of why one couldn't just decide how the creatures would flock using simple stick figures then add the rest of the models later.

        In any case, we're in no position to judge how accurately a film recreated the behaviours of creatures that haven't been found in the wild for millions of years. Certainly we can infer a lot based on what we can observe in their distant descendants but it's still one of those things that takes some dramatic license (just like Lego gene

      • by OzPeter ( 195038 )

        Can this claim even be proven or disproven?

        Silly question on a nerd site, you don't "prove" anything with science, and Jurassic park was a movie, not a scientific model.

        Years and years ago I saw some academic research that modeled bird flocking with a simple "Try and keep a constant distance from my neighbors" algorithm. The video (vector graphics with the birds rendered as simple triangles) of the animations produced a very lifelike behavior of a flock of birds flying around and through groups of fixed objects. I'd say if anything that the animators of Jurassic park were probably aware of such techniques.

        • a simple "Try and keep a constant distance from my neighbors" algorithm

          Probably the same algorithm birds use when they fly into a tree -- "try to keep away from branches". They just do it ten or one hundred times faster than we can, so it be black magic to us. A tight loop, run with highly priority, and featuring a few key bits of inline code.
        • by Kielistic ( 1273232 ) on Monday July 28, 2014 @08:49AM (#47549421)
          The model you are talking about is called boids [wikipedia.org]. It is a relatively simple AI model that demonstrates emergent behaviour.
      • Any hypothesis that doesn''t allow being disproven isn't science. period. That's hardly silly to point out. I may have been too polite by phrasing it in basic English - maybe I should have jumped right on a bunch of working scientists with the bold claim they had departed fully from the basic scientific method, before actually taking the time to read the original paper in detail and recrunching all their numbers, if that would make you feel better. Better yet, why don't you take "Let's You and Him Fight" el

    • Ever hear of the "jinx" tradition? It is when you say something at the exact same time you have to do "x". X is irrelevant (sorry math teacher). The point is that if two or more creatures are intent on doing the exact same thing - say eating grass while looking out for predators, they are very likely to spot something strange at the exact same time, both reacting at the exact same time. It is not telepathy, because the creatures are not reacting to each other.

      The same thing often happens in flocks.

  • by Anonymous Coward

    So cold. Liquid helium cold.

  • Smart Birds (Score:4, Funny)

    by Anonymous Coward on Monday July 28, 2014 @03:07AM (#47548099)

    Bird#1 - "Hey lets do our formation exercise as always after 5 seconds we turn right then left after 6 seconds....the humans will think we are telepathic or something"

  • Where there is not the additional pixels to explain the change in direction, because flocking.

  • . . .and it be showin' like a mother flocker [youtube.com]!
  • by disposable60 ( 735022 ) on Monday July 28, 2014 @07:24AM (#47548827) Journal

    Does that explain why their singing voices are so high-pitched?

    • by JustOK ( 667959 )
      no, it's because most of them crack their nuts with their beaks.
      • no, it's because most of them crack their nuts with their beaks.

        LOL, once again, I am going to have to invoke rule #34.

        Somewhere, in a dark and nasty corner of the interwebs is the human analog to this.

        Now, excuse my, I have to go apply brain bleach.

  • with a 'flock of birds' CPU cooler?

    Somehow I don't think it would be as effective as liquid He

  • swept through the flock at a constant speed between 20 and 40 meters per second.

    I'm not even sure gcc would let you do this. But what do I know? I don't blame cigarettes for the death of Eric Garner either.

  • That's very cool.
  • Last time the bird flock was mentioned it was about how a flock flies past an obstacle without colliding. Something about each bird maintaining its position by maximizing the distance to its nearest neighbors. The math would work out such that each bird would form a vertex in a Delaunay tessellation and the "space" associated with each bird would form a Voronoi polyhedron.

    I was kind of scared. You know, you spend all your life learning computational geometry and suddenly a flock of shearwaters or starling

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