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Re: The origin of flight: from the water up



----- Original Message -----
From: "James R. Cunningham" <jrccea@bellsouth.net>
Sent: Monday, March 25, 2002 7:16 AM


> > 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.

Yet some birds do it (don't know just how extended their wings are). And
however they get in, flapping around underwater is common.

> > > 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?

OK... fast flapping might not. The first (relatively slow) downstroke,
though, certainly would, wouldn't it? :-)