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Re: Protoavis is part pterosauromorph, no details about Novacaesareaia, etc.



Jaime A. Headden wrote-

<Thankfully, Jaime realizes that he has also formed opinions based on written
and illustrated data instead of personal examination and presented them on his
website.>


My observations are not limited to publications, actually, but while I have
viewed some specimens personally, most are treated from photos viewed
personally. So yes, I have personally examined several fossils.

Surprisingly enough, I also "personally view" photos for information quite often (I suppose the alternative would be to have photos described to me?). And like you, I've personally examined several fossils as well.


Since the website in question (http://qilong.8m.com/) has a disclaimer
about the utility of the data and my sources and all references used are
listed, I am also on stable ground as to changing data. Similarly, unlike
Mickey, I do not have "opinions" formed on these data, but follow data until
there is no more data; hopefully, I will be dead before there is an end to data
that can be gleaned from the fossils I hope to study.

My website also has a disclaimer and I also list all references used. Twist semantics however you wish, you and I gather and disseminate data in the same way.


<Where were you to chew out Scott for using the term 'silesaurid'?
http://dml.cmnh.org/2005Aug/msg00175.html>

Offlist, actually. Though admittedly in my reply to Scott Hartman publically
on this topic (http://dml.cmnh.org/2005Aug/msg00232.html) I used "silesaurid"
once in quotes and once without. Scott is aware of my sticklership and I felt
he was professional enough to slide (especially as the Science Director for the
Wyoming Dinosaur Museum). If any taxon is applied of late with a stem like -id
on the end, this usually applies to an -idae, yet neither does one exist nor
does it seem reasonable yet to use it until such a clade is diagnosed to allow
reference of taxa to this group.

Seems we're both guilty of the same slip-up of not putting "silesaurid" in quotes then. You'll note I never even refer to Silesaurus nor any taxon based on it on my website, except to place it in the ex-theropod cladogram in an unnamed clade with Eucoelophysis.


<In any case, I agree with Irmis, Nesbitt et al. that Eucoelophysis is a
'silesaurid' after comparing the photos in its description with the figures of
Silesaurus. The femur is especially convincing, as Silesaurus shares
Eucoelophysis' supposedly apomorphic proximal groove and is nearly identical in
shape.>

*snip*
But since this is
all based on two papers, and not on personal examination, this is all very
speculative, and we have not seen Nesbitt et al.'s data on the subject, but
until then, the proximal groove doesn't resolve the position of two taxa in my
book without a more extensive comparison and supportive data between two or
more taxa. The rest of the data that I can see to refute this argument seem to
support a plesiomoprhic use for the proximal groove.

You make some good points, several of which I noticed myself when comparing the material. However, the figures of Silesaurus are either small illustrations or reconstructed composites, similar to Madsen's (1976) Allosaurus monograph. They may not represent its true morphology accurately. The dorsals of Eucoelophysis are not illustrated. The lack of a fibular crest argues against a theropod identity for Eucoelophysis, and its presence in Silesaurus is a local apomorphy of the taxon. Coelophysoid and ceratosaur trochanter morphology is sexually(?) dimorphic, and this could extend further down the dinosauromorph line to complicate matters of femoral comparison. Much of the proximal end of pubis AMNH 2706 (not a paratype of Coelophysis longicollis, but referred later by Cope) is reconstructed in plaster. Oddly, the distal femur and proximal tibia are in some ways more similar in Silesaurus and Coelophysis than either is to Eucoelophysis. Nesbitt et al.'s eventual publication should be quite interesting.


Mickey Mortimer