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



"T. Mike Keesey" <tmk@dinosauricon.com> wrote:
> On 24 Jun 2001 archosaur@usa.net wrote:
> 
> > It is shown that a small group of dinosaurs had feathers, or possibly
some
> > other proto-feathery stuff, but the majority of dino finds still show them
to
> > be scaled.
> 
> Of course all dinosaurs are scaled -- many just have feathery integument
> as well -- just like today's dinosaurs (neornithean birds). Of course, I
> suppose you meant "scaly all over".
> 
> As I mentioned in another post, that "small group" is at LEAST
> Clade(_Sinosauropteryx_ + _Passer_), which is hardly small.

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

Compared to the rest of Dinosauria, I'd call it pretty darn small.


________________________________


And the group may be as large as _Tetanurae_, or even larger if certain
all-scaled large forms are secondarily so. 

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

Again, unless scutes are derived feathers, I don't see any reason to believe
that a group of animals that were feathered, would do a complete reversal
instead of just losing the feathers and sticking with skin.

__________________________________


> Impressions showing scales all over the body are
> known only from certain large cerapods (ceratopsids and hadrosaurids), a
> few sauropods (_Tehuelchesaurus_, ?_Camarasaurus_, embryonic            >
titanosaurs), and two carnotaurine abelisaurs (_Aucasaurus_ and         >
_Carnotaurus_). Someone please let me know if I missed anything.) For  > the
vaaast majority of fossil dinosaurs, we have no data about the skin.

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

Tyrannosaurs too, until shown otherwise.

As for the vast majority, is this not also true for most of the animals within
the clade _Sinosauropteryx_ + _Passer_. Now if we want to play cladistics with
it and assume that those scaled animals are indicative of all the rest of the
dinosaurs within those clades, wouldn't that then mean that scales are basal
to Dinosauria and, hence, the default dinosaur skin type (at least up till
maniraptors)?


Jura


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