Re: Coordinated behavior among birds, fish, and insects

From: Dace (
Date: Sun Aug 26 2001 - 20:35:53 BST

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    Subject: Re: Coordinated behavior among birds, fish, and insects
    Date: Sun, 26 Aug 2001 12:35:53 -0700
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    From: "Vincent Campbell"

    > <It was Potts, not Selous, who measured the reaction time in
    > dunlins. Potts
    > > compared flocking behavior to a chorus line. While the reaction time of
    > > humans is 194 milliseconds, the gap between kicks in a chorus line is
    > > 107 milliseconds. Potts said the people in the chorus line are able to
    > > predict when their turn will arrive, because they see it coming out of
    > > corner of their eye. He claimed this effect applied to birds in a flock
    > > as
    > > well. The problem is that, half the time, the wave approaches each bird
    > > from behind, implying that they have 360 degree vision. And even if the
    > > birds could see the wave coming, this doesn't explain how they're able
    > > move so precisely with it. Despite being densely packed together, the
    > > birds
    > > never bump into each other. You may balk at my use of that dangerous
    > > work,
    > > "never," but birds in a flock have *never* been observed to collide (at
    > > least not by anyone who was taking notes).>
    > >
    > Birds capacity to see behind them, given the position of their eyes
    > of the side of their head (apart from birds of prey who have more front
    > facing eyes and- notably- don't flock), is actually very good. They have
    > blind spot immediately behind their tail, but birds do not fly in straight
    > lines (I believe that's something to do with the aerodynamic effects of
    > birds flying), but in positions slightly to left or right of the bird in
    > front of them (the famous Geese flying V is the obvious example). That
    > gives them ample visual room to see what the birds behind them are doing.

    Point taken. But does this also apply to fish in a school, which
    demonstrate the same apparently collective behavior? Can this account for
    the fact that birds are able to react to changes in flock direction faster
    than their measured reaction time? Can it account for their ability to move
    exactly in the right way when the shift comes?

    > <As I said, birds don't do math, any more than planets do. But that
    > doesn't
    > > mean they're not subject to field-based forces, such as gravitational or
    > > morphic, which are themselves describable mathematically.>
    > >
    > Of course they do mathematics. All organisms do- just not in the
    > conscious sense that we can with a piece of paper. Mathematical
    > calculations are being done by our brains all the time we're alive-
    > certainly when we're moving. All the time we're typing our e-mail
    > the brain is engaged in mathematical calaculations in relation to our hand
    > movements. Birds do it too when flying, landing hopping/running etc. etc.
    > So do other animals. That's not to say that organisms aren't subject to
    > forces, like gravity, but you just don't another new force to explain
    > organisms movement.

    Math is a language which describes reality more accurately than previous
    languages. Like them, it exists strictly within human imagination. The
    brain facilitates our mathematical abstractions, but it doesn't contain
    them. Abstraction is not a property of material objects. Even calculators
    don't do math. "Calculation" is merely our interpretation of the purely
    physical activities that occur in the machine.

    > Loathed as I am to give to some help with this theory, but perhaps a
    > better example than a flock of birds in flight for your arguments, might
    > a slime mold particularly when all those cells seem to conglomerate and
    > like a much larger single organism. Does Sheldrake have any views on
    > molds?

    Thanks for the suggestion.


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