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Re: Dinogeorge Digest #13




Dinogeorge@aol.com wrote:

> For the sake of completeness, this digest includes a few posts I've already
> sent to the list. Sorry if this is thus too long.
>
> Subj:   Re: ARTHROLOGY AND FLIGHT CONTROL
> Date:   98-08-02 21:29:14 EDT
> From:   Dinogeorge
> To:     m_troutman@hotmail.com
>
> In a message dated 98-08-02 19:00:51 EDT, m_troutman@hotmail.com writes:
>
> << The biggest fault of this hypothesis is that it would require a great
> amount of flight control. >>

I'm not sure that it takes all that much control.  I just checked my pilot's 
log,
and I soloed after 7 hr 25 minutes of instruction (about average, though I was
delayed a bit because I had one arm in a sling due to a motorcycle accident -- 
my
instructor didn't want to turn me loose till I removed the sling and bandages --
and his liability).  I'd expect any proto-bird worth his salt to be able to
acquire control technique quicker than I did.

> George wrote:

> I'd say the biggest fault of the "wind-gust" paradigm is that it requires a
> gusty climate to persist steadily, day in and day out, for several million
> years while the proto-birds evolve the ability to take off using the gusts.
> Come on. Where do these people come up with this rot??

About all that's required to establish wind gusts is a planet with an 
atmosphere,
a heat source (suns work nicely for this), and days and nights that alternate 
on a
fairly regular basis.  Adding lakes, oceans, and land helps the mix 
considerably.
Conditions wouldn't need to be as gusty as they are now, particularly since the
(probably) denser atmosphere would potentially make flight possible at lower
speeds and higher body masses than today.  If anyone knows a way to inhibit the
heat engine that powers our atmospheric transients for even a few days, much 
less
several million years, I'd be interested learning the mechanism.  You can rest
assured that however flight originated, the little beasties learned to handle
turbulence early on, because it was a regular occurence.  As everyone knows,
pterosaurs had a couple of truly elegant mechanisms for automatically 
compensating
for gust loading, so their structural layout indicates that there was some
turbulence present in the atmosphere during the time birds were developing 
flight.
Also, no one ever said the proto-birds were dependent on the gusts -- only that
the gusts helped.
All the best,
Jim