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Re: Ornithoms, Parrots, and others
From: Adam Yates <A.Yates@zoo.latrobe.edu.au><"'email@example.com '"@usc.edu>
Subject: RE: Ornithoms, Parrots, and others
>>I'll accept that prediction, and add in its stead that the next decade
>likely see the following in Jurassic rocks: basal oviraptorosaurs, basal
>dromaeosaurs, basal bullatosaurs (if this remains a distinct clade
>Maniraptoriformes: if not, both proto-troodonts and
>and basal tyrannosaurids.
>Well, some might squeeze in post-Archae; pre-Archae is really the deal.
>Frankly, I'm surprised you're willing to go for it.
>There is one recent paper in Palaontologische Zeitschrift that I am
>no-one has mentioned in this discussion - perhaps the journal is real hard
>to find in the US ;)
>Anyway Jens Zinke describes the theropod fauna from the Guimarota
>microvertebrate locality in Portugal.It is dated as early Kimmeridgian so
>is pre - Solnhofen (just). Only teeth are known but they include
>Archaeopteryx, Compsognathus,a velociraptorine, a dromaeosaurine,a probable
>troodontid, a probable tyrranosaurid, a probable allosaurid and something
>akin to Richardoestia. Now I know some might say teeth. If you don't
>believe in tooth identifications you would have to explain why the tooth
>characters that can be used to diagnose K coelurosaur groups suddenly no
>longer diagnose these groups when you dip below the J-K boundary. Another
>interesting point is that Archaeopteryx and Compsognathus are by far the
>most common taxa in the assemblage. This suggests that the paltry handfull
>of theropod skeletons in the Solnhoffen are only the most common elements
>a more diverse small theropod fauna running around the late Jurassic of
>Europe. Perhaps one day we will find a troodontid or velociraptorine at
>The ref is:
>Zinke, J. 1998. Small theropod teeth from the Upper Jurassic coal mine of
>Guimarota (Portugal). Palaontologische Zeitschrift 72: 179-189.
>In conclusion I'd say that Tom is backing a winner.
>There is also a paper by Galton and Van Heerden redescribing Blikanosaurus
>in the same volume.
Thanks for the info, Adam!
Hmmm! So at least we now know exactly why Tom was so confident. However,
the mention of coal mines reminds me of the Iguanodons in Belgium. Hadn't
they all fallen down into an earlier strata? Does the paper mention this
possibilty? Is the paper in English? This is the point at which I should
really call a raise, since I find it odd that this complex site should hold
the first trace of so many types. The frequency difference between the well
known Solnhoffen types and the others may be a clue here. Also the fact
that is was only micro stuff makes it even more doubtful. A carnivore tooth
*in* the skeleton of a good victim would have been pretty convincing.
Of course, I could stoop to the old BAMM trick and say "the
ancestors/descendants time reversal doesn't matter" but I don't think Archae
lasted long. A supernvoa species.
I think teeth can sometimes be almost as reliable as reasonable skeletons,
but they can wander, can't they. I'll need multiple bones with at least
some kind of connection.