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Where The New Papers Are
Upchurch, P., and Mannion, P.D. 2009. The first diplodocid from Asia and its
implications for the evolutionary history of sauropod dinosaurs. Palaeontology.
ABSTRACT: An isolated anterior caudal vertebra from the Qingshan (= Ch'ing
shan) Formation (Early Cretaceous) of Shandong Province, China, is redescribed
and shown to be an advanced diplodocid sauropod. This specimen possesses
several derived character states that are typically observed in advanced
diplodocoids or diplodocids, including the following: a mildly procoelous
centrum; a deep pit-like pneumatic fossa immediately below the caudal rib;
wing- or fan-shaped caudal ribs; and complex lamination of the neural spine.
The neural spine is apomorphically short and the centrum is short relative to
its height compared to those of other diplodocids, which, when coupled with the
specimen's unique geographical location and stratigraphical age, suggests that
it probably represents a new taxon. This caudal vertebra provides the first
convincing evidence that diplodocids were present in Asia, perhaps as a result
of the dispersal of neosauropod lineages from Europe and/or North America
during the Early Cretaceous. The discovery of a member of the Diplodocidae in
the Early Cretaceous also indicates that this clade did not become extinct at
the Jurassic/Cretaceous boundary as previously supposed.
Benson, R.B.J., Carrano, M.T., and Brusatte, S.L. 2009. A new clade of archaic
large-bodied predatory dinosaurs (Theropoda: Allosauroidea) that survived to
the latest Mesozoic. Naturwissenschaften. doi: 10.1007/s00114-009-0614-x.
ABSTRACT: Non-avian theropod dinosaurs attained large body sizes, monopolising
terrestrial apex predator niches in the JurassicâCretaceous. From the Middle
Jurassic onwards, Allosauroidea and Megalosauroidea comprised almost all
large-bodied predators for 85 million years. Despite their enormous success,
however, they are usually considered absent from terminal Cretaceous
ecosystems, replaced by tyrannosaurids and abelisaurids. We demonstrate that
the problematic allosauroids Aerosteon, Australovenator, Fukuiraptor and
Neovenator form a previously unrecognised but ecologically diverse and globally
distributed clade (Neovenatoridae, new clade) with the hitherto enigmatic
theropods Chilantaisaurus, Megaraptor and the Maastrichtian Orkoraptor. This
refutes the notion that allosauroid extinction pre-dated the end of the
Mesozoic. Neovenatoridae includes a derived group (Megaraptora, new clade) that
developed long, raptorial forelimbs, cursorial hind limbs, appendicular
pneumaticity and small size, features acquired convergently in bird-line
theropods. Neovenatorids thus occupied a 14-fold adult size range from 175 kg
(Fukuiraptor) to approximately 2,500 kg (Chilantaisaurus). Recognition of this
major allosauroid radiation has implications for Gondwanan paleobiogeography:
The distribution of early Cretaceous allosauroids does not strongly support the
vicariant hypothesis of southern dinosaur evolution or any particular
continental breakup sequence or dispersal scenario. Instead, clades were nearly
cosmopolitan in their early history, and later distributions are explained by
sampling failure or local extinction.
Moratalla, J.J. 2009. Sauropod tracks of the Cameros Basin (Spain):
identification, trackway patterns and changes over the Jurassic-Cretaceous.
Geobios. doi: 10.1016/j.geobios.2009.06.006.
ABSTRACT: Sauropod tracks make up only about 2% of the Cameros Basin
ichnocenosis, but they are present over the entire time span represented by the
Cameros sediments. The makers of these tracks are identified in terms of their
associated trackway pattern as either wide or narrow-gauge morphotypes.
Narrow-gauge trackways dominate the Tithonian-Berriasian interval. Wide-gauge
trackways become notably more common after the Berriasian, although
narrow-gauge trackways are still present and dominate the Cameros ecosystems
even during the Aptian. At this time an interesting equilibrium between
titanosauriform and non-titanosauriform sauropod trackways is evident, although
the latter are somewhat more common.
A review of the Iberian sauropod bone record suggests that Turiasauria +
Euhelopidae, Rebbachisauridae and Titanosauriformes are the three groups mainly
responsible for the Cameros Basin sauropod ichnocenosis.
D'Amore, D.C., and Blumenschine, R.J. 2009. Komodo monitor (Varanus
komodoensis) feeding behavior and dental function reflected through tooth marks
on bone surfaces, and the application to ziphodont paleobiology. Paleobiology
35(4):525-552. doi: 10.1666/0094-8373-35.4.525.
ABSTRACT: Most functional interpretations of ziphodont dentition are based on
limited morphometric, behavioral, and taphonomic studies, but few are based on
controlled observations of a modern ziphodont consumer. The purpose of this
study is to determine through controlled feeding observations if the behaviors
indicative of a ziphodont consumer are reflected by tooth marks left on bone
surfaces by Varanus komodoensis, the Komodo monitor. We document feeding
behavior, expand upon dental function, and correlate these aspects with tooth
mark production. We also discuss the significance and limits of applying these
data to fossil assemblages.
Goat carcasses were fed to 11 captive individuals. V. komodoensis modifies
bone surfaces extensively. Individuals exhibit a âmedial-caudal arcâ when
defleshing, followed by inertial swallowing. Bone crushing was not observed.
The vast majority of tooth marks are scores, with pits being significantly less
common. Tooth furrows and punctures are rare. âEdge marksâ are produced on flat
elements. Marks are elongate and narrow, with variable lengths and curvature.
Over one-third of the marks occur within parallel clusters. Striations are
evident on 5% of all marks.
Both feeding behavior and tooth marks indicate that ziphodont crowns are
ideal for defleshing by being drawn distally through a carcass. Crowns are
poorly built for crushing, and within-bone nutrients are acquired through
swallowing. Mark production is a by-product of the distal crown movement during
the flesh removal process. Scores are the consequence of apical dragging. Edge
marks and striated scores result respectively from distal and mesial carinae
contact. Mark curvature is the consequence of arcing motions. Parallel clusters
may result from repetitive defleshing strokes and/or from multiple crown
contacts during a stroke.
These observations can be used to draw functional, behavioral, and
taphonomic interpretations from fossil assemblages. When they are provisionally
applied to theropod tooth marks, similar crown function and defleshing behavior
with little bone crushing is apparent. Differences occur concerning mark
frequency and curvature, relating potentially to taphonomic biases and rostral
Ji, Q., Ji, S.-A., and Zhang, L.-J. 2009. First large tyrannosauroid theropod
from the Early Cretaceous Jehol Biota in northeastern China. Geological
Bulletin of China 28(10):1369-1374.
(âerects _Sinotyrannus kazuoensis_ from the Jiufotang Formation)
Xing, L.-D., Dong, H., Peng, G.-Z., Shu, C.-K., Hu, X.-D., and Jiang, H. 2009.
A scapular facture in Yangchuanosaurus hepingensis (Dinosauria: Theropoda).
Geological Bulletin of China 28(10):1390-1395.
Jourdan, F., Renne, P.R., and Reimold, W.U. 2009. An appraisal of the ages of
terrestrial impact structures. Earth and Planetary Science Letters
286(1-2):1-13. doi: 10.1016/j.epsl.2009.07.009.
ABSTRACT: There are 174 confirmed impact structures known on Earth (e.g.,
http://www.unb.ca/passc/ImpactDatabase/; late 2008) but a far smaller number of
impact structures has yielded a well-constrained age. Precise and accurate age
constraints are crucial for (1) correlating causes and effects on the bio- and
geosphere of catastrophic processes, (2) better constraining the impactor flux
through geological time and evaluation of potential impact periodicity, (3)
calibrating the absolute chronostratigraphic time scale, (4) calibrating the
age of within-crater continental sedimentary deposits (e.g., for regional
paleo-climatic analysis), and (5) correlating impact events and distal impact
Of these 174 listed impact structures only a few have precisely
constrained ages (mostly obtained using radio-isotopic techniques, e.g. U/Pb
and 40Ar/39Ar), with only 25 ages having a stated precision better than Â 2%,
and a mere 16 ages with a precision better than Â 1%. Yet, even the accuracy of
some of these ages can be challenged and probably improved based on more
detailed interpretations and statistically more rigorous data analysis.
Although geochronologists are often circumspect and advise caution in accepting
calculated ages, these ages tend to propagate into the literature without
further critical evaluation, are considered ârobustâ, and become widely
accepted ages. A review of the age data for the 25 short-listed structures
suggests that 11 ages are accurate, 12 are at best ambiguous and should not be
reported with any uncertainty, and 2 are not well characterized at all. We
report detailed examples of misleading ages and/or age uncertainties (e.g.,
poor stratigraphic constraints, data over-interpretations, ambiguity due to
inconsistent results), and highlight the robustness of the 11 well-defined
ages. Based on observations and modeling, suggestions are made on how to obtain
better ages by carrying out adequate sample preparation. We also indicate how
to interpret ages for non-geochronologists. This brief review should be
interpreted as a call for immediate, drastic qualitative and quantitative
improvements of the ages of terrestrial impact structures.
Godefroit, P., Codrea, V., and Weishampel, D.B. 2009. Osteology of Zalmoxes
shqiperorum (Dinosauria, Ornithopoda), based on new specimens from the Upper
Cretaceous of NÄlaÅ-Vad (Romania). Geodiversitas 31(3):525-553.
ABSTRACT: NÄlaÅ-Vad is a new fossil locality discovered in 2002 in the SÄnpetru
Formation (Maastrichtian, Late Cretaceous) of the HaÅeg Basin (Transylvania,
Romania). This site has, among others, yielded the most complete skeleton that
can be referred to the ornithopods dinosaur Zalmoxes shqiperorum Weishampel,
Jianu, Cziki & Norman, 2003, but also isolated elements belonging to both
juveniles and adult individuals. This material provides new information about
the anatomy of Z. shqiperorum, and about the inter- and intraspecific
variability within Zalmoxes. Zalmoxes robustus (Nopsca, 1902) and Z.
shqiperorum were apparently sympatric species in Transylvania by latest
Cretaceous time. The co-existence in the same locality of two closely-related
species is not an isolated case among ornithopod dinosaurs.
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
"Education is the only thing people
shell out a lot of money for...and
then do everything possible to avoid
getting their money's worth."