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Re: [Re: [Combined answer: Feathered/scaly theropods: trying to make the point.]]



"Zoe Heraklides" <z_heraklides@hotmail.com> wrote:
>
>
> "Jura" writes:
> >
> >
> >So to rephrase: "All dinosaurs should be considered scaly by default,
> >unless
> >there is evidence to the contrary."
> >
>
>
> I think the crux of the trouble here is that the opinions expressed here are

> very strong and forceful in their presentation. Yet, the opinions are based

> on little evidence - and based more or less (mostly "more") on Jura's
> assertions about dinosaurs and the Yixian localitie(s):
> (1) all dinosaurs are the same where skin/integument is concerned, so we
> have no right to picture ANY dinosaurs were feathered unless we can prove
> they all were.
> (2) all feathred dinosaurs are found in one tiny locality, which were
> susceptibel to some freaky fungal/dendritic phenomonen which look so much
> like feathers that paleontologists  havebeen fooled into thinking they are
> feathers.
> (3) if some specimens shows preserved integument than they ALL should. In
> other words, Yixian mammals should show hair, Yixian ornithopods should show

> scutes/scales etc. (But preservation was differential according to the
> nature of the intgegument -  just like Solnhofen and Messel and Santana.)
>
> Assertions 1,2,3 are incorrect. I am not going to accuse "Jura" of being
> uninformed in this discussion/debate. I would say that the strength of the
> opinions are not matched by Jura's grasp of the topic. To say that he has
> not aware of any Yixian birds beside Confuciusornis hints at this. There are

> at least 20 species of bird so far described, and some have been described
> in major easy-to-get journals (Science, Nature).

+++++++++++++++++++++++

Most of the references to Liaoning that I got came off of the "fuzzy" dino
papers and none were particularly good. _Confusciornis_ was mentioned in
practically all of them, but I never got any good refs for it in the
citations. They either lead to a certain bird book, who's title escapes me, or
weren't mentioned at all.

_______________________


>
> Also:
> >>Check out
> >>posts regarding dino metabolism, or theropod behaviour and see how often
> >>maniraptor gets exapted to all theropods and occasionally, all dinosaurs.
>
> "Exaptation" is an evolutionary term, coined by Gould (I think in the
> 1980's). It means when an existing structure takes on a new (derived)
> function - and that new functiuon may replace the old one. I think your
> usage may not be right. Do you mean "extrapolate?"
>
>
> Regards, Zoe

+++++++++++++++++

Well my definition for exapt simply states it as another way of saying:
"extended"

In other words, maniraptor often gets extended to include all theropods and
occasionally all dinosaurs when talks of feathery integument are concerned.

Jura


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