Re: Some questions & feathered Allosaurs?

["Simon M. Clabby" <dinowight@yahoo.co.uk>]

 --- Nick Gardner <ratites637@hotmail.com> wrote: >
Ivan Kwan wrote: 
> >
> >And with the porcupine-tailed psittacosaur,
> suddenly feathered 
> >ornithischians don't look so bizarre to me either.
> Maybe basal ornithopods 
> >like _Hypsilophodon_ had some primitve fuzzy
> integument, a feature that 
> >maybe newly hatched iguanodonts & hadrosaurs
> possessed. At the moment 
> >though, the thought of giving my Triceratops a
> porcupine tail is still too 
> >bizarre to contemplate. (Though you never know what
> you may find out...)
> >
> 
> CMIIW, but the preserved integumentary structures of
> *Psittacosaurus* sp. 
> were not feathers, not even in the sense of
> dino-fuzz.  
> 

True, As Mayr et al compared them to be more like
mammal spines, as seen in hedgehogs and porcupines.
They are also hollow, and it has been suggested that
they may have been pigmented, so maybe these are
modified scales used for display, although of course
the colour can only be speculated on, which may make
them analogous, if not homologous, to bird feathers,
providing they didn't appear further back in
dinosaurian evolution, and have become more different
over time.

Also, I was under the impression that Psittacosaurs
were considered by some workers to not bee ancestral
to Neoceratopians, as they had only four digits on the
manus, whereas the quadrupedal Neoceratopians all had
five digits on the manus, so the Triceratops of your
art would not need to look like a porcupine, or have I
completely misunderstood my phylogenetics again?.

Yours awaiting criticism,

Simon M. Clabby


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