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Date:    Tue, 27 Jun 1995 14:52:20 GMT
>From:    "York H. Dobyns" <ydobyns@TUCSON.PRINCETON.EDU>
Subject: Re: No brontosaurus?

In article <01HS6CJ3LN768YBYD8@delphi.com> Stephen Carville <PAGAN@DELPHI.COM> 
> The lack of transitional forms was one of the very first challenges
> leveled against evolution.  When Archaeopteryx was discovered to be
> feathered in 1861 that objection began to dissolve amongst reputable
> scientists.  The evidence for Archaeopteryx continued to mount and
> is now so compelling that even the ICR has stopped maligning that
> poor almost-but-not-quite-a-bird publically and usually trys to
> ignore it.  Since Archaeopteryx there have been hundreds of
> transitional forms discovered in the fossil record.  Typically, this
> pathetic argument only survives in those who read 150 year old anti-
> evolution arguments and who are either unaware of the currently
> known fossil record or refuse to believe it.

Actually, there's a subtler and even more pernicious form of the "no
transitional forms" argument out there: you get rid of transitional
forms by defining them away. For example, Archaeopteryx is clearly, to a
reasonable observer, transitional between dinosaurs and birds;
skeletally it's a small dinosaur, but it had feathers, and the feathers
on its arms were configured into weak but marginally functional wings.

However, among modern life forms feathers are an unambiguous diagnostic
for birds, and are frequently used as such in introductory biology
texts: all birds have feathers, and only birds have feathers. So a
creationist can use a definition like that as though it were a logic
gate, and declare: "Archeopteryx had feathers, ergo it was a bird. QED.
No transitional forms. Any dinosaurlike fossil we find, ever, will
either have scales, and therefore be a dinosaur, or have feathers,
and therefore be a bird. No transitional forms." The fact that some

of these "birds" have teeth, long tails, and clawed fingers on their
wings is conveniently ignored among the triumphant trumpeting.

York Dobyns             ydobyns@phoenix.princeton.edu
Honest skeptics must be willing to question *their own* beliefs, as
well as those of people with whom they disagree.