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Re: Science feather strength debate
On 11/1/2010 11:28 PM, Tim Williams wrote:
> It could have; but any such flight stroke would be
Yes. But then, they were rudimentary birds, were they not? You have to
start somewhere, and it does not seem unlikely in principle that the
very first "bird" that could generate thrust or lift w/ a downstroke was
not capable of a full upstroke as outlined by Mike H.
> _Confuciusornis_ would have to wait for a breeze of the right
> magnitude and direction in order to pull off this "soar".
Erik makes an excellent point in that some environments the "breeze" is
*always* there. No waiting. These environments may be limited in area,
but exist in evolutionarily significant time frames.
There is a very high probability that gliding species adapted to (as
example) a forest environment were fortuitously exposed on a daily basis
(in mid-flight!) to such conditions over the course of the planet's history.
Assuming a lack of previously established competition, the result might
well be a creature that (perhaps having previously evolved the
capability of "locking" it's "wings" to support it's weight while
gliding) had a limited range of motion relative to an upstroke.