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Re: Sinosauropteryx tail colors



Tim, so how do you interpret Juravenator?  If memory serves, patches
of fossilized Juravenator skin (from the tail base and hind leg) shows
primarily scales... but I think I remember reading something about how
there may be  traces of simple, filamentous feathers present as well.
Xu Xing suggested that the presence of scales on the tail of
Juravenator could mean that the feather coat of early feathered
dinosaurs was more variable than seen in modern birds... so this goes
along with what we see in the conclusion from this colorization
article. I also think that Xu considered it most likely that
Juravenator and other feathered dinosaurs simply possessed more
extensive scales on their bodies than modern birds.

Anyway... I guess where I'm going with this is that I agree with you.
Much care needs to be taken with interpreting what covered an ENTIRE
body given the reality of preservational/taphonomic artifacts.

Kris



On Thu, Jan 28, 2010 at 7:51 PM, Tim Williams <tijawi@yahoo.com> wrote:
>
>
> Don Ohmes <d_ohmes@yahoo.com> wrote:
>
>> Not sure I disagree (although given my track record it
>> might seem likely), but wouldn't the more exact analogy be
>> claiming that bone itself evolved as a "display mechanism"?
>
>
> I wouldn't have thought so.  It's the selection pressure that's common here, 
> not the mechanism by which structures are engendered.
>
>
> In general, and as others have alluded to, finding support for the hypothesis 
> that feathers originally evolved for display (and not thermoregulation) is 
> going to be tricky.  The presence of feathers on some parts of the body (like 
> a midline crest, or on the tail) and not others is not enough evidence by 
> itself.  The absence of feathers on most of the body will have to be shown to 
> be real, and not a preservational (taphonomic) artifact.  For example, there 
> will have to be integument preserved *instead* of feathers, such as scales.
>
>
> Cheers
>
> Tim
>
>
>
>