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Re: The origin of flight: from the water up




Waylon Rowley wrote:

> David Marjanovic wrote:
>
> > but Feduccia mentions many species of auks and
> > petrels that fly straightly through waves.
>
> Maybe they simply fold up their wings and shoot
> through them.

That may be the likely scenario.  If they were to enter a wave with
their wings extended, instantaneous lift and drag forces would increase
by a factor of more than 800.  That could put some serious stress on the
joints.

> > from gliding to flying [...] that transition is probably impossible,
> as flapping destabilizes a
> > glider (screws up its angle of attack and all that). No living
> glider flaps.

While I don't think that gliding would neccesarily be expected to lead
to flapping, why would flapping have to destabilize a glider?  And
flapping doesn't necessarily screw up the aoa.  At high advance ratios
one doesn't even have to kill the lift during the latter half of the
upstroke.

JimC