Re: Coordinated behavior among birds, fish, and insects

Date: Mon Aug 27 2001 - 02:45:23 BST

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    Subject: Re: Coordinated behavior among birds, fish, and insects
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    On 26 Aug 2001, at 12:35, Dace wrote:

    > 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
    > only
    > > > 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
    > the
    > > > 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
    > to
    > > > 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
    > a
    > > 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?
    Yes, it does; the overwhelming majority of schooling fish have side-
    set eyes, just as birds do. And the most likely hardwired
    algorithmic 'autopilot' reaction time of birds in a flock, their natural
    habitat, as was pointed out before, would most certainly be faster
    than their in-a-foreigh-evvironmen and individual (thus more
    processed and mediated) laboratory reaction time. And the
    algorithm evolved to be the most effective solution to the problem of
    danger to a flock, so it's right a lot of the time, but it's not right ALL
    of the time - otherwise predatory birds such as hawks, falcons, and
    other raptors, who predominately hunt within flocks of prey, would
    have long ago starved to extinction.
    > > <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
    > messages
    > > 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.
    Flocking birds and schooling fish, among other species possess
    evolved and hardwired algorithms, which respond to particular
    circumscribed stimuli in paradigmatic and automatic ways; it's also
    known as instinct.
    > > 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
    > be
    > > a slime mold particularly when all those cells seem to conglomerate
    > > and
    > move
    > > like a much larger single organism. Does Sheldrake have any views
    > > on
    > slime
    > > molds?
    > Thanks for the suggestion.
    > Ted
    > ===============================================================
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