Received: by alpheratz.cpm.aca.mmu.ac.uk id BAA06545 (8.6.9/5.3[ref pg@gmsl.co.uk] for cpm.aca.mmu.ac.uk from fmb-bounces@mmu.ac.uk); Mon, 27 Aug 2001 01:28:14 +0100 X-Originating-IP: [209.240.220.151] From: "Scott Chase" <ecphoric@hotmail.com> To: memetics@mmu.ac.uk Subject: Re: Coordinated behavior among birds, fish, and insects Date: Sun, 26 Aug 2001 20:25:38 -0400 Content-Type: text/plain; format=flowed Message-ID: <F262Nxvpuu4Y2U4WfkT00012733@hotmail.com> X-OriginalArrivalTime: 27 Aug 2001 00:25:38.0837 (UTC) FILETIME=[CC262450:01C12E8E] Sender: fmb-bounces@mmu.ac.uk Precedence: bulk Reply-To: memetics@mmu.ac.uk
>From: "Dace" <edace@earthlink.net>
>Reply-To: memetics@mmu.ac.uk
>To: <memetics@mmu.ac.uk>
>Subject: Re: Coordinated behavior among birds, fish, and insects
>Date: Sun, 26 Aug 2001 12:35:53 -0700
>
>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.
>
>
In _A New Science of Life_ (1995/1981. Park Street Press. Rochester,
Vermont) Sheldrake talks about slime molds (see chapter 2). Scott Gilbert
also discusses the slime mold in his text _Developmental Biology_ (1997.
Sinauer Associates, Inc. Sunderland, Massachusetts). Interesting stuff.
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