Received: by alpheratz.cpm.aca.mmu.ac.uk id HAA19619 (8.6.9/5.3[ref pg@gmsl.co.uk] for cpm.aca.mmu.ac.uk from fmb-bounces@mmu.ac.uk); Mon, 20 Aug 2001 07:55:44 +0100 Message-ID: <003501c128e9$d29d4de0$c024f4d8@teddace> From: "Dace" <edace@earthlink.net> To: <memetics@mmu.ac.uk> References: <2D1C159B783DD211808A006008062D3101745FF8@inchna.stir.ac.uk> Subject: Coordinated behavior among birds, fish, and insects Date: Sun, 19 Aug 2001 13:02:02 -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
> <Obviously. The question is how the birds manage to maintain the
> right
> > distance, particularly when the whole flock turns on a dime. Either the
> > brain is running an incredbly elaborate motion program or the flock is a
> > morphic field in which the birds are "particles." While the latter
> > possibility might strike you as being "weird," the former possibility
> > would
> > require neural computing processes unimaginably more powerful and rapid
> > than
> > anything humans have ever devised.>
> >
> When a human catches a ball in flight, they actually perform a
> complex mathematical calculation that only a pretty good mathematician
could
> work out on paper. Yet children can catch balls in flight with no
knowledge
> of the complex maths involved. Indeed, brains operate complex
mathemetical
> operations all the time to control movements etc. Why's that a problem
for
> you that needs the MR macguffin? The whole flock appears to us to turn on
a
> dime. What actually happens is that the lead bird responds to conditions
in
> flight with a slight turn that resonates rapidly through the flock, bird
by
> bird, into what ends up looking like a massive sharp turn for the whole
> flock. Each bird makes a relatively small turn in relation to the birds
> near it. They are not calculating the movement of the entire flock, but
> only their own movement in relation to the birds immediately around them
> which doesn't require huge amounts of brain power, and can easliy be done
by
> lots of organisms.
The planets are not performing Keplerian calculations as they sweep across
the sky, and neither are birds in a flock. If they had to do the
stupendously complex math involved, their brains would blot out the sky.
The naturalist Edmund Selous has studied flocking behavior in dunlins. He
found that one or two birds located somewhere in the flock would initiate a
change in direction, and this change would then radiate through the flock.
He tested their reaction time in a laboratory and found it to be at 38
milliseconds. But the change in direction of a flock radiates from bird to
bird at 15 milliseconds, more than twice as fast as their reaction time.
Also, the 38 millisecond reaction is always arbitrary, unlike the precisely
coordinated behavior of the flock.
As schools of fish demonstrate, there's no individual in charge of the
group. The fish in the front of the school might seem to be leading it
until the whole school makes a sharp left turn, and suddenly the "leaders"
are the fish who happened to be on that side. When a predator arrives on
the scene, the school will sometimes engage in a "flash expansion," which
looks kind of like a bomb going off. The fish dart away from the predator
in as little as .02 seconds. Yet they never collide. They behave as a
single organism whose parts are coordinated.
This group-mind effect is revealed in the arch-building behavior of
termites. Researchers commonly observe termites building columns, and if
one column is close enough to another, then the termites, at a certain
height, will begin building the columns together into an arch. Though the
termites are blind, and none of them are running back and forth between the
columns to measure the difference in their locations, the two columns always
meet up perfectly. It was assumed that the termites use their sense of
smell to guide the columns together, but when Eugene Marais stuck a steel
plate between two columns, he found that they still matched perfectly.
Marais also discovered that all the coordinated activities of the termites
are somehow facilitated by their queen. Even if the queen is isolated from
the workers in a compartment, when the queen is killed, all work instantly
stops.
Phenomena such as this can only be explained according to the field model.
Either these fields are expressions of equations, as Goodwin argues, or
they're stabilized through resonance with previous similar systems.
> In human society a similar kind of process, albeit kind of in
> reverse, is evident in traffic. In heavy traffic, when cars travel too
> closely together jams emerge out of apparently nothing. They're called
> shockwaves (IIRC), and are the net effect of small acts of braking caused
by
> cars travelling at different speeds, changing lanes, and climbing hills
etc.
> in heavy traffic. This works back down the line to result in complete
> standstills of traffic. The Jam doesn't stay in one place but moves
slowly
> backwards, with the jam increasing in size. None of this requires any
> collective resonance, but simply the compound result of lots of little
> individual responses to individual circumstances (the car in front changes
> lanes suddenly making you brake, that compounds down the road behind you
to
> a mile long tail back).
Sheldrake has never suggested that traffic jams are caused by morphic fields
(though morphic resonance with past drivers might cause a progressive
improvement in our ability to drive safely).
Ted
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