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Re: The "ideal" Eumaniraptoran arm motion

-----Original Message-----
From: Jonathan <spockjr@email.msn.com>
To: larryf@capital.net <larryf@capital.net>; Betty Cunningham
Cc: dinosaur@usc.edu <dinosaur@usc.edu>
Date: Monday, March 01, 1999 8:53 AM
Subject: Re: The "ideal" Eumaniraptoran arm motion

>>>If the ancestral appendage-movement that originated flapping is flapping
>>>itself we have a circular arguement.
>>>-Betty Cunningham
>>>Larry Febo wrote:
>>>> It seems MUCH more likely, ...to me,
>>>> that many of these "Avian" features are holdovers from a previous
>>>> ancestor and are actually "proof" that these creatures are secondarily
>>>> flightless.
>>>-- >
>>No, ...not "circular",...more like a precise motion in a strictly level
>>plane (well, maybe a slight figure eight), ...ideally suited for avian
>>flight (a very specific function, leaving very little room for error), but
>>(somehow) also an ideal motion for capturing prey!
>Icthyostega had feet which were ideally suited for walking as well
>but it lived in water most likely 99% of the time although its ancestors
>were undoubtedly fully aquatic, so what's your point?
Ideally suited for walking??............ How fast could it run?
My point is that evolution, in evolving something as complex as flight,
usually does it in short steps, each step being somewhat adaptive to the
enviornment. A gliding stage leading towards flight takes this into account.
Feathered limbs on running theropds as an adaptation for enhancing the
capture of prey dosen`t seem likely (to me anyway).