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Re: BAAD BCF



In a message dated 95-12-01 02:16:43 EST, ornstn@inforamp.net (Ronald
Orenstein) writes:

>Can we say "possibly" secondarily flightless?  "Allegedly" secondarily
>flightless?  Secondarily flightless  according to George Olshevsky and Greg
>Paul (and ANYONE else???)?  This is certainly not generally accepted as far
>as I have ever heard.

It's accepted by me, and since it's my message, I'll leave off the
qualifiers. You may add them as you like.

_Archaeopteryx_ undoubtedly had several (probably tens of) megayears of
flight evolution in its ancestry in order to have evolved the flight feathers
and other adaptations for flight observed in the specimens. Dromaeosaurids
such as _Deinonychus_ are anatomically so similar to _Archaeopteryx_ (check
out the character matrices in Holtz and Chiappe's recent articles) that their
common ancestral form _must_ have appeared within those several megayears. So
the dromaeosaurids must have been secondarily flightless. That's the gist of
the argument, anyway: it took a lot longer to develop flight in the first
archaeopterygiform than it took to lose it in the dromaeosaurids.

>i don't mean to nitpick this to death but obviously this list is read by
>many non-scientists (including school children) who may be encountering
>these messages for the first time and treat statements like the above as
>though they were proven facts.  I think it behooves us to label hypotheses
>or personal views, or we will be behaving no more responsibly than the
>writers of Jurassic Park who have now convinced a generation of filmgoers
>that T rex's vision was based on movement and Dilophosaurus spat poison.

By the time we're finished labeling everything with qualifiers, the sense of
the sentences is buried. People who subscribe to the dinosaur list for any
length of time will surely become accustomed to the styles of the authors of
the postings after a while.