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My Sister's New Papers
Apologies again if any of these are duplicates, but I don't think any of these
have been specifically mentioned on the list yet...
Renesto, S., Spielmann, J.A., and Lucas, S.G. 2009. The oldest record of
drepanosaurids (Reptilia, Diapsida) from the Late Triassic (Adamanian Placerias
Quarry, Arizona, USA) and the stratigraphic range of the Drepanosauridae. Neues
Jahrbuch fÃr Geologie und PalÃontologie Abhandlungen 252(3):315-325. doi:
ABSTRACT: Previous detailed descriptions of relatively complete drepanosaurid
material make it possible to recognize isolated drepanosaurid elements from
other localities. The identification of isolated elements from the USA and
Great Britain extended the geographical distribution of the group and
encouraged a review of Triassic collections for characteristic elements of this
family. In this paper, isolated vertebrae previously described as problematic
reptiles from the famous Placerias Quarry, near St. Johns, Arizona, USA are
re-identified as drepanosaurids. These specimens represent the oldest
occurrence of this family, which is earliest Adamanian.
Prieto-MÃrquez, A., and Wagner, J.R. 2009. Pararhabdodon isonensis and
Tsintaosaurus spinorhinus: a new clade of lambeosaurine hadrosaurids from
Eurasia. Cretaceous Research. doi: 10.1016/j.cretres.2009.06.005.
ABSTRACT: We present new anatomical information showing that Koutalisaurus
kohlerorum, from the Maastrichtian of Lleida Province, northeastern Spain, is
most probably the junior synonym of Pararhabdodon isonensis from the same
region. Dentary and maxillary characters previously considered as
autapomorphies of K. kohlerorum and P. isonensis, respectively, are shown to be
synapomorphies uniting the latter with Tsintaosaurus spinorhinus from the
Campanian of the Wangshi Group, Shandong Province, China. This study provided
conclusive evidence of the presence of the Lambeosaurinae in Europe.
Tsintaosaurus spinorhinus and Pararhabdodon isonensis were inferred to form a
clade of basal lambeosaurines characterized by a maxilla with an elevated
articular facet for the jugal (continuous with the ectopterygoid ridge) and an
extremely medially projected symphyseal region of the dentary. This clade
originated in Asia during the middle or late Campanian. Pararhabdodon isonensis
or its ancestors migrated from Asia to the Iberian island of the European
archipelago. Reconstruction of ancestral areas by Fitch parsimony attributes
the European occurrence of P. isonensis to a single dispersal event from Asia
no later than middle to late Campanian.
Buffetaut, E., and Morel, N. 2009. A stegosaur vertebra (Dinosauria:
Ornithischia) from the Callovian (Middle Jurassic) of Sarthe, western France.
Comptes Rendus Palevol. doi: 10.1016/j.crpv.2009.05.001.
ABSTRACT: A dinosaur vertebra found in the course of road works in the âChevain
Marlsâ (marine Callovian) of the Vermont outlier, near the village of BÃthon
(Sarthe, Pays-de-la-Loire, western France) is described and referred to a
stegosaur (cf. Lexovisaurus). It is the first record of a dinosaur in the
Middle Jurassic of that area. The specimen was probably derived from the
floating carcass of an animal that had lived on the emerged areas of the
Armorican Massif, near which the Chevain Marls were deposited. This fossil is
an addition to the short list of stegosaur remains reported from France.
Klembara, J., and Welman, J. 2009. The anatomy of the palatoquadrate in the
Lower Triassic Proterosuchus fergusi (Reptilia, Archosauromorpha) and its
morphological transformation within the archosauriform clade. Acta Zoologica
90(3):275-284. doi: 10.1111/j.1463-6395.2008.00358.x.
ABSTRACT: The anatomy of the palatoquadrate ossifications of the Lower Triassic
archosauromorph Proterosuchus fergusi from South Africa is described. It
consists of two ossifications, the epipterygoid and the quadrate, which were
joined by cartilage in life. The margins of the cartilage are clearly indicated
by ridges and grooves on the dorsal surface of the pterygoid. The epipterygoid
ossification consists of two structures: the anteroposteriorly expanded basal
portion and, dorsally from it, an extending, slender, ascending process. From
the anterior margin of the basal portion of the epipterygoid, a plate-like
structure, herein called the lamina epipterygoidea anteromedialis, extends
anteromedially to form the anterolateral wall of the cavum epiptericum.
Comparisons with the similarly constructed embryonal and adult epipterygoid
components of Sphenodon punctatus show that the anteromedial lamina of the
epipterygoid of P. fergusi is an additional component of the epipterygoid of
this species and that this lamina is absent in the former species. However, a
structure in a topologically similar position to the anteromedial lamina of the
epipterygoid of P. fergusi is present in the palatoquadrate of Alligator
mississippiensis. In the latter species, the structure is called the lamina
palatoquadrati anterior; it ossifies in membrane and forms the dorsolateral
cover of the huge trigeminal ganglion. It is hypothesized here that the
anteromedial lamina of the epipterygoid of P. fergusi and the anterior lamina
of the palatoquadrate of A. mississippiensis are most probably homologous
structures and are present in both the basal and one of the crown taxa of the
archosauromorph clade, respectively.
Martin, A.J. 2009. Dinosaur burrows in the Otway Group (Albian) of Victoria,
Australia, and their relation to Cretaceous polar environments. Cretaceous
Research. doi: 10.1016/j.cretres.2009.06.003.
ABSTRACT: Three enigmatic structures in an outcrop of the Otway Group (Albian)
of Victoria, Australia, compose the first known evidence suggestive of dinosaur
burrows outside of North America and the oldest from the fossil record. The
most complete of the Otway structures nearly matches the size and morphology of
a burrow attributed to the only known burrowing dinosaur, Oryctodromeus
cubicularis from the Upper Cretaceous (Cenomanian) of Montana (USA). The
suspected burrows cross-cut alluvial facies and overlie nearby strata
containing dinosaur tracks. The structures contain identical sand fills in
their upper portions, implying a near-synchronous origin and filling; graded
bedding in the most complete structure also indicates passive filling of an
originally open structure. This probable burrow is a 2.1 m long, gently
descending, semi-helical tunnel, with a near-constant diameter (about 30 cm)
that connects with an enlarged terminal chamber. The structures are unlikely to
have been caused by physical or chemical sedimentary processes, and hence are
considered as biogenic structures; moreover, their size and morphology imply
tetrapod tracemakers. Burrow allometry indicates tracemakers with a mass of
10-20 kg, matching size estimates for small ornithopods from the Otway Group.
Burrowing behavior in hypsilophodontid-grade dinosaurs, which compose most of
the dinosaurian assemblage in the Lower Cretaceous of Victoria, was proposed
previously as an adaptation for surviving formerly polar conditions in
southeastern Australia. This paradigm is explored in detail, particularly
through actualistic examples of tetrapod burrowing in cold climates. These
structures may provide the first clues of ornithopod burrowing in these extreme
environments, while also establishing search images for similar structures in
other Lower Cretaceous outcrops in Victoria.
Pol, D., Turner, A.H., and Norell, M.A. 2009. Morphology of the Late Cretaceous
crocodylomorph Shamosuchus djadochtaensis and a discussion of neosuchian
phylogeny as related to the origin of Eusuchia. Bulletin of the American Museum
of Natural History 324:1-103.
ABSTRACT: We describe a new specimen of the fossil crocodyliform taxon
Shamosuchus djadochtaensis from the Late Cretaceous Djadokhta Formation. The
new specimen consists of an almost complete skull found in association with
postcranial material. Because it is considerably more complete than the
holotype, the new specimen permits proper diagnosis of Shamosuchus
djadochtaensis and offers new information for exploring its phylogenetic
The phylogenetic analysis conducted here improves taxon sampling of
neosuchian crocodyliforms with respect to previous approaches to crocodyliform
systematics and reveals that Shamosuchus djadochtaensis bears important
information toward an understanding of the relationships of advanced
neosuchians and the evolutionary origin of Eusuchia. Shamosuchus djadochtaensis
is found to be the sister group of Rugosuchus nonganensis, comprising an Asian
clade diagnosed by the presence of a sagittal ridge on the dorsal surface of
the frontal, confluent openings for the exit of cranial nerves IXâXI, a
posterior region of the palatine bar between suborbital fenestra that is flared
posteriorly, and a longitudinal ridge on the lateral surface of the angular.
This clade is inferred to be the sister group of Eusuchia, to the exclusion of
Bernissartia fagesii and the Glen Rose form, based on the absence of an acute
anterior tip of the frontal that wedges between the nasals, the presence of
rodlike neural spines in the posterior cervical vertebrae, procoelous cervical
vertebrae, and the presence of hypapophyses in the three anteriormost dorsal
Incorporating the new information into the phylogenetic analysis indicates
the decoupled nature of the evolutionary history of procoely in different
regions of the vertebral column and the eusuchian type of palate, both
traditionally considered as diagnostic of Eusuchia. All these features have
complex evolutionary histories with several cases of convergences and
reversals. Finally, a review of all the available evidence on the diversity of
advanced neosuchians suggests this group achieved a worldwide distribution and
a remarkable morphological diversity, pushing their evolutionary origins back
to the Jurassic.
Jablonski, D., and Finarelli, J.A. 2009. Congruence of morphologically-defined
genera with molecular phylogenies. Proceedings of the National Academy of
Sciences 106(20):8262-8266. doi: 10.1073/pnas.0902973106.
ABSTRACT: Morphologically-defined mammalian and molluscan genera (herein
âmorphogeneraâ) are significantly more likely to be monophyletic relative to
molecular phylogenies than random, under 3 different models of expected
monophyly rates: â63% of 425 surveyed morphogenera are monophyletic and 19% are
polyphyletic, although certain groups appear to be problematic (e.g.,
nonmarine, unionoid bivalves). Compiled nonmonophyly rates are probably extreme
values, because molecular analyses have focused on âproblemâ taxa, and
molecular topologies (treated herein as error-free) contain contradictory
groupings across analyses for 10% of molluscan morphogenera and 37% of
mammalian morphogenera. Both body size and geographic range, 2 key
macroevolutionary and macroecological variables, show significant rank
correlations between values for morphogenera and molecularly-defined clades,
even when strictly monophyletic morphogenera are excluded from analyses. Thus,
although morphogenera can be imperfect reflections of phylogeny, large-scale
statistical treatments of diversity dynamics or macroevolutionary variables in
time and space are unlikely to be misleading.
Mateus, O., Dyke, G.J., Motchurova-Dekova, N., Kamenov, G.D., and Ivanov, P.
2009. The first record of a dinosaur from Bulgaria. Lethaia. doi:
ABSTRACT: A portion of a left humerus from the Upper Maastrichtian of Vratsa
district (NW Bulgaria) is shown to be from a non-avian theropod dinosaur: this
is the first record of a dinosaur from Bulgaria. We describe this bone, suggest
that it most likely pertains to an ornithomimosaur, and discuss the fossil
record of other similar taxa of Late Cretaceous age that have been reported
from Europe. To investigate the taphonomy of this fossil, rare earth element
(REE) analysis is combined with strontium (Sr) isotope data to confirm that
this Bulgarian dinosaur bone was initially fossilized in a terrestrial
environment, then later re-worked into late Maastrichtian marine sediments.
Bleweiss, R. 2009. The tail end of hummingbird evolution: parallel flight
system development in living and ancient birds. Biological Journal of the
Linnean Society. doi: 10.1111/j.1095-8312.2009.01240.x.
ABSTRACT: Evolutionary innovations are central to debates about biological
uniformitarianism because their very novelty implies a distinct evolutionary
dynamic. Traditional scenarios for innovations in the development of avian
powered flight exemplify the kinds of distinctions considered to occur at
different times during the history of innovations. Thus, the progressive change
of the wing stroke mechanism early in its evolution is considered to have
imposed strong functional and historical constraints on tail shape diversity,
whereas attainment of the modern flight stroke mechanism is considered to have
liberated the tail to radiate into a wide variety of other functions and forms.
Detailed analyses of living hummingbirds revealed that these highly aerial
birds actually expressed many parallel functional constraints and historically
progressive patterns observed earlier in avian history: (1) more basal lineages
had relatively weak wing muscles (patagial muscles and tendons, TPB), convex to
square tails, and more linear flight employed in nonterritorial foraging; (2)
more derived lineages had a stronger TPB, forked tails, accentuated growth of
tail fork, and more manoeuvrable and agile flight employed in territorial
foraging; and (3) the most derived lineage had the strongest TPB, greatly
reduced tails, and mainly bee-like flight. These associations make functional
sense because convex tails increase stability and efficiency in linear flight,
concave tails augment lift for turning flight in territorial defence, and tails
become aerodynamically disadvantageous if the wings provide sufficient lift.
Derived hummingbird lineages also demonstrated the same expansion of tail shape
and taxonomic diversity associated with perfection of the modern wing stroke
mechanism earlier in avian history. Thus, living hummingbirds are a microcosm
of overall avian flight evolution. Other living avian ('aerial courser') and
extinct reptilian (Pterosaur) clades with extraordinary flight abilities
provide evidence for similar p!
followed by later radiation) at the limits of the flight performance envelope
throughout vertebrate history. Correlated evolution of TPB and tail form
suggests that natural selection on an integrated flight system was the
principal mechanism fostering the avian patterns, although strengthening of
wing muscles in derived lineages may have facilitated expansion of caudal
morphological diversity through a balance between natural and sexual selection
on males. These findings suggest that wing muscles, locomotor integration, and
phylogenetic patterns are essential for understanding function and adaptation
of tails in living as well as ancient birds.
Motani, R. 2009. The evolution of marine reptiles. Evolution: Education and
Outreach 2(2):224-235. doi: 10.1007/s12052-009-0139-y.
ABSTRACT: Reptiles have repeatedly invaded marine environments despite their
physiological constraints as air breathers. Marine reptiles were especially
successful in the Mesozoic as major predators in the sea. There were more than
a dozen groups of marine reptiles in the Mesozoic, of which four had more than
30 genera, namely sauropterygians (including plesiosaurs), ichthyopterygians,
mosasaurs, and sea turtles. Medium-sized groups, such as Thalattosauria and
Thalattosuchia, had about ten genera, whereas small groups, such as Hupehsuchia
and Pleurosauridae, consisted of only two genera or less. Sauropterygia and
Ichthyopterygia were the two longest surviving lineages, with 185 and 160
million years of stratigraphic spans, respectively. Mesozoic marine reptiles
explored many different swimming styles and diets. Their diet included fish,
cephalopods, other vertebrates, and hard-shelled invertebrates, whereas no
herbivore is known at this point. Sauropterygians and ichthyopterygians gave
rise to cruising forms that probably invaded outer seas. Intermediate forms
that led to the cruising species are known in Ichthyopterygia but not as much
in Sauropterygia. Discovery of new fossils should eventually reduce the gap in
the fossil record.
Clark, J.M., and Xu, X. 2009. Evolutionary transitions among dinosaurs:
examples from the Jurassic of China. Evolution: Education and Outreach
2(2):236-247. doi: 10.1007/s12052-009-0137-0.
ABSTRACT: Dinosaurs have captured the popular imagination more than any other
extinct group of organisms and are therefore a powerful tool in teaching
evolutionary biology. Most students are familiar with a wide variety of
dinosaurs and the relative suddenness of their extinction, but few are aware of
the tremendous longevity of their time on Earth and the richness of their
fossil record. We first review some of the best-known groups of dinosaurs and
discuss how their less-specialized relatives elucidate the path through which
each evolved. We then discuss our recent discovery of Yinlong downsi, a distant
relative of Triceratops, and other fossils from Jurassic deposits in China to
exemplify how the continuing discovery of fossils is filling out the dinosaur
Turner, A.H., Nesbitt, S.J., and Norell, M.A. 2009. A large alvarezsaurid from
the Late Cretaceous of Mongolia. American Museum Novitates 3648:1-14.
ABSTRACT: We report a new alvarezsaurid, Kol ghuva, from the Late Cretaceous of
Mongolia that demonstrates that the clade was not restricted to small taxa
(3â15 kg). The specimen was found at the Ukhaa Tolgod locality, which has
previously produced only a single diminutive alvarezsaurid, Shuvuuia deserti.
Although known only from a well-preserved right foot, the new taxon is
diagnosable by the following combination of characters: extensor grooves on
digit IV phalanges; robust flexor tubercle on pedal unguals; MT III does not
reach ankle; accessory dorsomedial flange absent on the medial side of the
distal end of the MT II; MT II shorter than MT IV; and MT III extends higher
proximally than other alvarezsaurids (more than Â total metatarsus length). The
new taxon provides additional insight into the diversity of this clade and the
dinosaurian assemblage of Ukhaa Tolgod.
Balanoff, A.M., Xu, X., Kobayashi, Y., Matsufune, Y., and Norell, M.A. 2009.
Cranial osteology of the theropod dinosaur Incisivosaurus gauthieri (Theropoda:
Oviraptorosauria). American Museum Novitates 3651:1-35.
ABSTRACT: We provide a description of the holotype skull of the unusual
oviraptorosaur Incisivosaurus gauthieri. Previous phylogenetic analyses have
placed this taxon firmly within Oviraptorosauria near the base of the clade;
however, until now only a cursory description of this important specimen was
available. The presence of many primitive characteristics (e.g., maxillary and
dentary teeth as well as an extended palate and rostrum) indicates that the
observed similarities between avians and derived oviraptorids are convergences
rather than shared derived characters. In addition, we clarify previous
descriptions of several ambiguous anatomical features, most notably of the
palate. We also employ computed tomographic (CT) analysis, which allows for a
more complete description of the braincase and the reconstruction of an
endocranial endocast. CT imagery reveals features that were before
unobtainable, such as the presence of a replacement tooth behind the large
rodentiform incisor in the premaxilla. This arrangement indicates that although
the incisiform teeth of I. gauthieri are morphologically distinct they are
replaced in typical archosaurian fashion.
Jerry D. Harris
Director of Paleontology
Dixie State College
225 South 700 East
St. George, UT 84770 USA
Phone: (435) 652-7758
Fax: (435) 656-4022
"Experience is what you get when
you didn't get what you wanted."