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Caveat (was:Re: SAUROPOD FEATHERS)



At 14.41 16/02/02 -0800, you wrote
 Cosesaurus
has a "dorsal frill", Sharovipterx has scales on the tail and snout, but
smooth neck skin.

and David Marjanovic wrote:

> Sharovipterx has scales on the tail and snout, but
> smooth neck skin.
Really? Cool.

Dear all
Not strictly on topic (dino feathers): but I feel that something like "according to...." should be added to statements about these two critters. In fact there are lots of divergent opinions . The first describer, Ellemberger, saw "feather-like" impressions in Cosesaurus ( he thought it was a *bird* ancestor), subsequently David Peters saw "dorsal frills" and other similar structures (he considers it as a *pterosaur*-related taxon) while others (Sanz, for instance) saw "nothing" at all (they think it is simply a prolacertiform). . As far as I know and have seen, the preservation is quite peculiar and it is extremely difficult to state what there really is, and I for one, would share the third group (this does not mean I dismiss Dave Peters hypothesis), to me, the impressions if ever present, are of nothing else than sedimentary structures. For what concerns Sharovipteryx, Unwin et al. wrote : "The integument covering the skull ,NECK (emphasis is mine) trunk .... bore small tubercular or keeled scales". On the other hand Dave Peters has a different opinion (AFAIK he is working on this, thus I cannot tell more) . I do not know the reference for the naked neck (?), and having not seen Sharovipteryx first hand I do not have any personal opinion.
What I mean here, however, is this: while we have lots of hypotheses on these animals, the revidence is really scarce or at least highly controversial, thus it might be advisable to be dubitative when quoting about their features or using them to support any assumption.
All the best,


                                        Silvio Renesto


_ "The Wise Man is like a bamboo tree; simple, upright, and useful, but hollow inside"

                                                Lao Tzu

Silvio Renesto

Dipartimento di Scienze della Terra
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