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Re: Feathers on Bloody Everything



Dinogeorge writes:
>The integumentary structures on Sinosauropteryx are not protofeathers; 
>they're true feathers something like those of kiwis: modified, because of 
>secondary flightlessness, into hairlike filaments from the kinds of feathers 
>found in flying birds. Sinosauropteryx is far too late in time to have 
>retained without significant evolutionary modification the kinds of 
>protofeathers that might someday be found on "non-dinosaurian avians." 
>Longisquama has something closer to what protofeathers might have looked like.

I am no expert on this but based on what I have heard from Alan Brush, and
on papers I heard at the Ostrom Symposium, I see no support for this
statement.  Certainly I think Alan Brush, a recognized authority on feather
microstructure, would have recognized a kiwi-like degenerate feather when
he saw one - and none of the people I have heard who have examined the
fossils in detail has suggested that there is anything about these
structures that would classify them as filamentous feathers.  Brush is even
reluctant to call them protofeathers.

Time has nothing to do with it.  The platypus survives today with a whole
suite of characters that, by George's argument, it could not possibly have
retained.

It sounds far more to me like George is doing a Feduccia in reverse: ie: "I
believe that Sinosauropteryx and other dinosaurs like it evolved from
flying birds or protobirds - these must have had true feathers - therefore
the structures on Sinosauropteryx CANNOT be protofeathers no matter what
the evidence shows".   I'm sorry, but if the physical evidence does not
provide us with characters showing that these structures are filamentous
feathers, then it is the hypothesis, not the evidence, that must give way.

And my apologies to George if he is referring to actual physical evidence
that has emerged since the Ostrom Symposium - if he is, I'd sure like to
hear about it!

--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
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