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Godzilla vs. New Papers



Sadleir, R., Barrett, P.M., and Powell, H.P. 2008. The anatomy and
systematics of Eustreptospondylus oxoniensis, a theropod dinosaur from the
Middle Jurassic of Oxfordshire, England. Monograph of the Palaeontographical
Society (Publication No. 627) 160:1-82.

ABSTRACT: Recent work on theropod phylogeny has concentrated on the
interrelationships of taxa that lie close to the ancestry of birds
(coelurosaurs), whereas only a small number of studies have investigated the
evolution of more primitive theropods (e.g. basal tetanurans). Ghost
lineages implied by theropod phylogenies suggest that the Middle Jurassic
was an important time in tetanuran evolution, witnessing the initial
radiation and diversification of the clade. However, Middle Jurassic
theropod specimens are rare and often incomplete.
     The holotype specimen of Eustreptospondylus oxoniensis, from the Middle
Oxford Clay (upper Callovian) of Oxfordshire, England, represents the most
complete Middle Jurassic theropod specimen from Europe. This taxon therefore
has the potential to shed much needed light on basal tetanuran evolution at
a critical time in the clade's history. Although several previous authors
considered the anatomy and systematics of Eustreptospondylus, none of these
accounts provided a comprehensive description and their utility is therefore
limited.
     Here, we provide a detailed redescription of Eustreptospondylus and
confirm its phylogenetic position as a basal member of Spinosauroidea. The
taxon exhibits several anatomical features that appear to be incipient
versions of the highly specialized character states found in more derived
members of the clade (e.g. development of the premaxillary/maxillary
embayment). The results of this work also suggest that Spinosauroidea may
have originated in the Middle Jurassic of Europe, later dispersing to
Gondwana.




Bonde, J.W., Varricchio, D.J., Jackson, F.D., Loope, D.B., and Shirk, A.M.
2008. Dinosaurs and dunes! Sedimentology and paleontology of the Mesozoic in
the Valley of Fire State Park; pp. 249-262 in Duebendorfer, E.M. and Smith,
E.I. (eds.), Field Guide to Plutons, Volcanoes, Faults, Reefs, Dinosaurs,
and Possible Glaciation in Selected Areas of Arizona, California, and
Nevada. Geological Society of America Field Guide 11.

ABSTRACT: This field trip covers sedimentological and paleontological
research being conducted on the Jurassic Aztec Sandstone and Lower
Cretaceous Willow Tank Formation in Valley of Fire State Park. Valley of
Fire State Park is located in southern Nevada, just outside of the town of
Overton. The Jurassic Aztec Sandstone is equivalent to the Navajo and Nugget
Sandstones; these formations together record an aerially large erg complex
along the western margin of North America during the time of deposition.
Invertebrate and vertebrate ichnofossils are not uncommon in portions of
these Jurassic formations.
     The Willow Tank Formation is composed of the deposits of both a braided
and anastomosed fluvial system. This system drained off the paleohigh of the
Sevier fold and thrust front to the west, during Early Cretaceous time.
Recently a diverse vertebrate assemblage has been discovered from this
formation. The fauna of the Willow Tank Formation are similar to other Early
Cretaceous faunas from western North America. The vertebrate remains
recovered include three taxa of fish, three to four taxa of turtle,
crocodilian, iguanodontian, thyreophoran, dromaeosaur, tyrannosauroid, two
theropod ootaxa, and a titanosauriform. In addition to the vertebrate
elements, two fern morphotypes have been found. Through the course of this
field trip participants will see extensive exposures of Aztec Sandstone,
including vertebrate ichnofossils. Participants will also hike to vertebrate
bearing beds of the Willow Tank Formation.




Snively, E., and Cox, A. 2008. Structural mechanics of pachycephalosaur
crania permitted head-butting behavior. Palaeontologia Electronica
11(1):3A:1-17.

ABSTRACT: Pachycephalosaurian dinosaurs have dorsally thickened crania and
uniquely shaped frontoparietal domes in some genera, suggested as evidence
for head- or flank-butting behavior. Trabeculae thought to have resisted
impact compression are present as only one histological zone of some
pachycephalosaur domes, and are surrounded superficially or replaced by
thick compacta in adults. The capabilities of pachycephalosaurian crania for
head-butting are testable by finite element analysis (FEA). FEA of 2- and
3-D dorsal skull shapes of adult Homalocephale and Pachycephalosaurus reveal
that the domes could withstand considerable impact force at certain closing
speeds, and that stress and strain would dissipate efficiently throughout
the dorsal portion of the skull before reaching the brain. Greater vaulting
of the dome permitted higher impact forces. An analysis restricted to the
frontoparietal dome of a subadult pachycephalosaurine, with material
properties corresponding to histological zones, shows higher compressive
strain (not less) in the trabecular region. The trabecular zone, if present,
would not have rigidly resisted compression but rather have allowed slight
elastic compression and rebound. Modeled keratinous coverings of varying
depth indicate reductions in force and energy transmission to underlying
bone. FEA therefore leaves open the possibility of head-butting in both
flat- and dome-headed pachycephalosaurs, especially at low collision speeds.


And, of course, the new ish of JVP:


Delfino, M., Codrea, V., Folie, A., Dica, P., Godefroit, P., and Smith, T.
2008. A complete skull of Allodaposuchus precedens Nopcsa, 1928 (Eusuchia)
and a reassessment of the morphology of the taxon based on the Romanian
remains. Journal of Vertebrate Paleontology 28(1):111-122. 

Ali, F., Zelenitsky, D.K., Therrien, F., and Weishampel, D.B. 2008. Homology
of the 'ethmoid complex' of tyrannosaurids and its implications for the
reconstruction of the olfactory apparatus of non-avian theropods. Journal of
Vertebrate Paleontology 28(1):123-133. 

Horner, J.R., and Goodwin, M.B. 2008. Ontogeny of cranial epi-ossifications
in Triceratops. Journal of Vertebrate Paleontology 28(1):134-144. 

de Valais, S., and Melchor, R.N. 2008. Ichnotaxonomy of bird-like
footprints: an example from the Late Triassic-Early Jurassic of northwest
Argentina. Journal of Vertebrate Paleontology 28(1):145-159. 

Hammer, W.R., and Smith, N.D. 2008. A tritylodont postcanine from the Hanson
Formation of Antarctica. Journal of Vertebrate Paleontology 28(1):269-273. 


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
 and     dinogami@gmail.com
http://cactus.dixie.edu/jharris/

"There's a saying that goes 'people who live in glass houses shouldn't throw
stones'... OK. How about...NOBODY should throw stones. That's crappy
behavior! My policy is 'no stone-throwing regardless of housing situation.'
There's an exception, though. If you're TRAPPED in a glass house...and you
have a stone, then throw it! What are you, an idiot? It's really 'ONLY
people in glass houses should throw stones'... provided they're trapped, in
a house... with a stone. It's a little longer, but you know..."
                                 --- Demetri Martin