Re: Bird /dino questions

[zenlizard@juno.com]

On Wed, 25 Mar 1998 10:30:29 +0100 Martin Human  writes:
> Just that, aerodynamically, I imagine you want fore and aft equilibrium
about the >COG for flight (the wiings?)
Yes and no  to the COG question.  Depends on what  you are trying to get
out of flight.  Equilibrium of any axis near the COG will give you
inherent stability in an aerodynamic design.  If you are trying to get
such stability, all three axes will have3 their equilibrium near the COG
of the animal.  Such an evolutionary path will be persued by birds who
make a career of long relatively stable fights  (soaring).  On the other
hand, birds who make a career of rapid changes of direction and speed 
(ie, maneuverability)  will persue a more-or-less inherently unstable
design, with the equilibrium point for one or more axes slightly offset
from the COG.  Note that this is a prediction, not a natural  'rule'  or
'law'.  I am approaching this from the standpoint of aerodynamics, not
evolutionary biology.
The consequence of this is that, it MAY, but does not automatically
follow, that a shortening of the tail will accompany a lightening of the
skull-depends on which path the lineage is following.  (Again, a
prediction, not a 'rule').
-zenlizard

Is it better to be half-assed or biased?
n=4

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