Re: Feathers on Bloody Everything

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

Jeff Poling wrote:
> 
> At 02:04 PM 10/6/98 -0400, Ronald Orenstein wrote:
> >In the midst of all the (premature?) excitement, folks, let's not forget
> >that there is pretty good evidence, in the form of integumentary casts and
> >similar fossils, that at least some adult dinosaurs did NOT have feathers -
> >including theropods like Carnotaurus.  Even if the new Therizinosaur is
> 
>    According to Holtz (DML 1997?), making the above conclusion is shaky
> because the skin impressions in question were not formed in sediments that
> would have preserved feathers, or similar integument, had they been present.
> 
        With all due respect to my good friend and partner in crime (even 
though he IS a Yalie...), I am not so sure his reasoning holds here.  We 
don't have the necessary taphonomic evidence to support this, especially 
when presumed soft-bodied or at least partially soft bodied invertebrates 
are known to survive both preservation in a very coarse-grain sandstone 
and subsequent low temperature-high pressure metamorphism into quartzites.
Give me a while to work out the geochemistry and the sedimentology of the 
Sihetun clastics before we go there, ok?


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Josh Smith
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