Received: by alpheratz.cpm.aca.mmu.ac.uk id MAA01381 (8.6.9/5.3[ref pg@gmsl.co.uk] for cpm.aca.mmu.ac.uk from fmb-bounces@mmu.ac.uk); Fri, 24 Aug 2001 12:36:31 +0100 Message-ID: <2D1C159B783DD211808A006008062D3101746042@inchna.stir.ac.uk> From: Vincent Campbell <v.p.campbell@stir.ac.uk> To: "'memetics@mmu.ac.uk'" <memetics@mmu.ac.uk> Subject: RE: Coordinated behavior among birds, fish, and insects Date: Fri, 24 Aug 2001 12:25:30 +0100 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain X-Filter-Info: UoS MailScan 0.1 [D 1] Sender: fmb-bounces@mmu.ac.uk Precedence: bulk Reply-To: memetics@mmu.ac.uk
<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. I
still don't buy the "they never bump into each other" statement.
<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.
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?
>> Wouldn't all social insects disperse on the death of the central
>> queen?
<They lose their social behavior instantaneously, before the message
has had
> a chance to be transmitted chemically.>
>
I doubt this very much indeed. What about the chemical messages
exuded by the dead queen themself that would waft through the mound with
some rapidity? There could be all sorts of highly subtle indicators that
produce what appears to be an instantaneous cease of social behaviour. Did
the experimenter genuinely observe every singly termite/ant (remember some
species have up to 20 million individuals in a nest)?
>> I have a feeling that the problems of MR are related to the
problems
>> of memetics, that some have suggested, namely- why have the
theory at all?
>> What does it add that isn't covered by other well established,
and
>> empirically supported theories? Etc. This discussion is a good
work-out
>>for those kinds of arguments.
<Ultimately, memetics will sink or swim with morphics.>
Yeah, that's what's beginning to worry me...
Vincent
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