Feathers on Bloody Everything

[smithjb@sas.upenn.edu (Joshua Smith)]

Allan Edels wrote:
> 
> I tend to agree with you on this George.
> 
> In a message dated 10/5/98 7:57:50 PM EST, jjackson@interalpha.co.uk writes:
> 
> << Wait until the ?feathers? turn out to be Caudipteryx style feathers;
> Sinosauropteryx style feathers aren?t feathers at all. >>
> 
> Actually, I kinda expect "Sinosauropteryx style feathers" to be on all
> dinosaurs, unless secondarily lost or converted into stuff like stegosaur
> plates, keeled scutes, spines, etc.
> 

        GROAN.  Now every bloody artist who hasn't done it before it 
going to put feathers on every critter out there.  Thanks, George.  I am 
as excited about all of this feather stuff as the next guy, particularly 
where I have been sitting rather firmly on the fence as far as avian 
origins are concerned for a long while.  

        Now everyone is going to toat parsimony in defense of putting 
feathers on EVERYTHING.  At the risk of sounding like a broken record, 
parsimony is an untested assumption, and systems violate it constantly.  
We need to be careful in painting it across the canvas in a single swatch 
of color.  Just because we have feathers in one clade, doesn't 
necessarilly mean that we are going to find them in all of them.  I will 
use the evidence that we have that physiology is not constant within and 
across the entire Dinosauria as support of that last statement.  I am 
going to kick the first person I see who draws a downy stegasaur.  Just 
don't go too too crazy, OK?

        Here is an interesting hypothesis that isn't new but that a few 
of us were kicking around on the 10th floor of the Cliff the other night:
What if feathers (downy junk, not "real") are ontogenetic for some 
theropods.  Juvenile feathered allosaurs?  Wow.  Both Holtz and I think 
that hypothesis kicks a lot of ass.


-- 
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Josh Smith
University of Pennsylvania
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