Received: by alpheratz.cpm.aca.mmu.ac.uk id UAA05933 (8.6.9/5.3[ref pg@gmsl.co.uk] for cpm.aca.mmu.ac.uk from fmb-bounces@mmu.ac.uk); Sun, 26 Aug 2001 20:37:33 +0100 Message-ID: <002301c12e66$52d64300$6f24f4d8@teddace> From: "Dace" <edace@earthlink.net> To: <memetics@mmu.ac.uk> References: <2D1C159B783DD211808A006008062D3101746042@inchna.stir.ac.uk> Subject: Re: Coordinated behavior among birds, fish, and insects Date: Sun, 26 Aug 2001 12:35:53 -0700 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Sender: fmb-bounces@mmu.ac.uk Precedence: bulk Reply-To: memetics@mmu.ac.uk
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?
> <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.
> 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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