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pterosaur flight & flocking behaviour



As a supplement to the work of Ken Dial and Colin
Pennycuick: with so much attention paid to flying
dinosaurs, those stump-tailed big-brained theropods,
overlooked is the variety (inferred, I confess) of
flight among pterosaurs. I have spent much time with
"swarm" behaviour literature, viz. predator/prey
dynamics as applied to theropods and prey. However,
"swarm" behaviour -- "flocking" -- among pterosaurs is
one avenue of speculation.
Craig Reynolds has done work on the dynamics of
flocking, and I would be curious to know the
professional reactions of DML forum members to his
work:
1987. Flocks, herds, and schools: a distributed
behavioral model. Computer Graphics 21(4):25-34
<www.red3d.com/cwr/papers/1987/boids.html>
1988. Not bumping into things: notes on "obstacle
avoidance". SIGGRAPH 88 paper, 1/5 August 1988
<www.red3d.com/cwr/nobump/nobump.html>
1993. An evolved, vision-based behavioral model of
coordinated group motion.
<www.red3d.com/cwr/1993/sab92.html>
Another scholar extrapolating "swarm" behaviour is Lee
Spector. Together with Jon Klein, he has nade
available:
2002. Evolutionary dynamics discovered via
visualization in the BREVE simulation environment.
<http://hampshire.edu/lspector/alife8-visualization.html>
In carefully reading this papers, one can substitute
"pterosaur" or "dinosaur" for "boid" etc., and make
interpolations (i.e., allow the imagination to "see"
how pterosaurs could possibly have engaged in flock
behaviour). In the main, as Craig Reynolds notes,
there are three steering behaviours in flocking: 1)
separation: avoid crowding; 2) alignment: steer
towards average heading of flockmates; 3) cohesion:
steer towards the average position of flockmates.
With the plethora of excellent pterosaur specimens
available, has Chris Bennett, e.g., thought of doing
computer simulations of the biomechanics of flight
among various pterosaur taxa? Is there fossil evidence
to indicate, e.g., their flight biomechanics was
analogous to flapping dinosaurs, or to bats? Bats do
not fly like dinosaurs. Unless my vision is failing, I
have viewed videotapes of nocturnal bat flight, and
have yet to see a flying theropod match their agility
(admittedly  enhanced by echolocation), except for
trochilids. I believe pterosaurs were better fliers
than some have contemplated.

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