Ben Creisler | 21 Oct 18:41 2014
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Allosaurus "thagomized" in pubic boot by Stegosaurus + other news

Ben Creisler
bcreisler <at> gmail.com

Some recent news and blog items:

Allosaurus "thagomized" in pubic boot by Stegosaurus tail spike

http://phys.org/news/2014-10-kung-fu-stegosaur.html

from:
https://gsa.confex.com/gsa/2014AM/webprogram/Paper247355.html

STEGOSAURIAN MARTIAL ARTS: A JURASSIC CARNIVORE STABBED BY A TAIL
SPIKE, EVIDENCE FOR DYNAMIC INTERACTIONS BETWEEN A LIVE HERBIVORE AND
A LIVE PREDATOR

BAKKER, Robert T., ZOEHFELD, K. Weidner, and MOSSBRUCKER, Matthew T.

Were carnivorous dinosaurs active predators, killing their own prey,
or scavengers depending upon carcasses found dead, or a mixture of
both? Today, large herbivores -- buffalo, rhinos, hippos -- often
fight back, damaging the attackers. Many dinosaurian herbivores
carried horns or spikes or other potentially dangerous weapons. Such
armament may have functioned in defense, courtship displays and
intraspecific combat. If dinosaurian predators regularly attacked
well-armed herbivores, we would expect to find predator skeletons with
wounds that can be attributed to particular herbivores.
We have analyzed an adult allosaur skeleton from the Brushy Basin
Member of the Morrison Formation, Late Jurassic, Albany County,
Wyoming. A stab wound penetrated through the lower pubis, piercing the
(Continue reading)

Ben Creisler | 21 Oct 17:20 2014
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Tyrannosauridae and Carnotaurinae (Theropoda) forelimb evolution and malformations in teratology

Ben Creisler
bcreisler <at> gmail.com

A recent online paper:

Geoffrey Guinard (2014)
Introduction to Evolutionary Teratology, with an Application to the
Forelimbs of Tyrannosauridae and Carnotaurinae (Dinosauria:
Theropoda).
Evolutionary Biology (advance online publication)
DOI: 10.1007/s11692-014-9296-1
http://link.springer.com/article/10.1007/s11692-014-9296-1

Conceptualisation of evolution requires new inclusions, as evidenced
by contributions brought by evolutionary developmental biology—the
evo-devo connection. Integration of teratology in an evolutionary
framework fits in this continuity. It highlights the production of
developmental anomalies (more or less drastic) over evolutionary
times, which become integral parts of groups and taxa. Originating in
Étienne Geoffroy Saint-Hilaire’s work, the contemporary independent
formulation of evolutionary teratology allows a better understanding
of some anatomical structures. The limbs of tetrapods are a promising
field of study as some changes in their shapes, proportions and
compositions are close to malformations observed in teratology. The
forelimbs condition of Tyrannosauridae and Carnotaurinae is a good
example. They are theropod dinosaurs characterised by different
anterior micromelias, codified following an anatomical nomenclature.
An association with the knowledge from developmental biology helps to
discern possible productive mechanisms of such micromelias, including
the influence of developmental rates, Hox genes, growth factors and
(Continue reading)

Ben Creisler | 21 Oct 00:52 2014
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Jehol Biota food-web models + Middle Jurassic Daohugou plants + more papers

Ben Creisler
bcreisler <at> gmail.com

A number of recent mainly non-dino papers that may be of  interest:

Masaki Matsukawa, Kenichiro Shibata, Kenta Sato, Xu Xing and Martin G.
Lockley (2014)
The Early Cretaceous terrestrial ecosystems of the Jehol Biota based
on food-web and energy-flow models.
Biological Journal of the Linnean Society 113(3): 836–853
DOI: 10.1111/bij.12368
http://onlinelibrary.wiley.com/doi/10.1111/bij.12368/abstract

The ancient terrestrial ecosystems of the Lower Cretaceous Yixian
Formation and the Jiufotang Formation, consecutive components of the
Jehol Group in Northeast China were reconstructed using an energy-flow
and food-web model. This model can be used to quantitatively estimate
population densities for ancient terrestrial vertebrates based on food
webs, net primary productivity, and three categories of
energy-transfer efficiency. The results indicate that densities
reached 866 individuals km−2 and 4122 individuals km−2 in two
ecosystems, respectively. The main component of the vertebrate fauna
of the Yixian Formation consisted of large herbivorous dinosaurs,
while much smaller avians dominated the Jiufotang fauna. The model
also indicates a temporal transition in the dinosaur fauna from the
Yixian fauna to the Jiufotang fauna in which theropods decreased and
ceratopsids became more abundant. We then compared these estimates of
biodiversity with the Early Cretaceous Choyr fauna of Mongolia, and
Tetori fauna of Japan using Simpson's diversity indices. Those
indices, based on biomass, indicate that the biodiversities of the
(Continue reading)

Ben Creisler | 20 Oct 20:26 2014
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Amber found with dinosaurs in Canada + other news

Ben Creisler
bcreisler <at> gmail.com

Some recent news items:

Amber found with Late Cretaceous dinosaurs

http://phys.org/news/2014-10-secrets-dinosaur-ecology-fragile-amber.html

from:

https://gsa.confex.com/gsa/2014AM/webprogram/Paper249774.html

AMBER ASSOCIATED WITH LATE CRETACEOUS DINOSAUR BONEBEDS IN WESTERN CANADA.
MCKELLAR, Ryan C., ENGEL, Michael S., TAPPERT, Ralf, WOLFE, Alexander
P., TAPPERT, Michelle C., and MUEHLENBACHS, Karlis.

The first report of inclusion-bearing amber in direct association with
a dinosaur bonebed was made in 2004. Subsequently, a range of fossil
deposits within the Late Cretaceous strata of Alberta and Saskatchewan
have been found to contain at least trace amounts of amber.
Improvements in processing techniques have allowed us to examine many
of these ambers for inclusions, in addition to conducting bulk
chemical analyses (Fourier-transform Infrared spectroscopy) to
establish source tree identity, and stable isotope analyses (of C and
H) to investigate both ecological conditions and events within the
paleo-forest. Here we will discuss preliminary findings from the Danek
Bonebed near Edmonton, Alberta (Horseshoe Canyon Formation,
Maastrichtian); Dinosaur Provincial Park, Alberta (Dinosaur Park
Formation, Campanian); Pipestone Creek Pachyrhinosaurus Bonebed near
(Continue reading)

Ben Creisler | 20 Oct 19:41 2014
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Habitat preference of mosasaurs indicated by rare earth elements

Ben Creisler
bcreisler <at> gmail.com

A new online paper:

T.L. Harrell and A. Pérez-Huerta (2014)
Habitat preference of mosasaurs indicated by rare earth element (REE)
content of fossils from the Upper Cretaceous marine deposits of
Alabama, New Jersey, and South Dakota (USA).
Netherlands Journal of Geosciences (advance online publication)
DOI: http://dx.doi.org/10.1017/njg.2014.29
http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9388902&fulltextType=RA&fileId=S0016774614000298

Knowledge of habitat segregation of mosasaurs has been based on
lithology and faunal assemblages associated with fossil remains of
mosasaurs and stable isotopes (δ13C). These approaches have sometimes
provided equivocal or insufficient information and, therefore, the
preference of habitat by different mosasaur taxa is still suboptimally
constrained. The present study is focused on the analysis of rare
earth element (REE) ratios of mosasaur fossils from the Upper
Cretaceous formations of western Alabama, USA. Results of the REE
analysis are used to infer the relative paleobathymetry associated
with the mosasaur specimens and then to determine if certain taxonomic
groups showed a preference for a particular water depth. Comparisons
are then made with mosasaur specimens reported in the literature from
other regions of North America from different depositional
environments. Results indicate that Mosasaurus, Platecarpus and
Plioplatecarpus may have preferred more restricted habitats based on
water depth whereas Tylosaurus and Clidastes favoured a wider range of
environments. Results also suggest that Plioplatecarpus lived in a
(Continue reading)

Ben Creisler | 20 Oct 17:35 2014
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Proterosuchus (Triassic archosauriform) revised taxonomy

Ben Creisler
bcreisler <at> gmail.com

A new online paper:

Martín D. Ezcurra and Richard J. Butler (2014)
Taxonomy of the proterosuchid archosauriforms (Diapsida:
Archosauromorpha) from the earliest Triassic of South Africa, and
implications for the early archosauriform radiation.
Palaeontology (advance online publication)
DOI: 10.1111/pala.12130
http://onlinelibrary.wiley.com/doi/10.1111/pala.12130/abstract

Proterosuchidae is one of the first clades of Archosauriformes
(archosaurs and closely related species) to appear in the fossil
record, with the richest sample of the group coming from the
Lystrosaurus Assemblage Zone (earliest Triassic) of South Africa. Four
nominal proterosuchid species were described from South Africa during
the twentieth century (Proterosuchus fergusi, Chasmatosaurus
vanhoepeni, Chasmatosaurus alexanderi and Elaphrosuchus rubidgei), but
interpretations of their taxonomy have been widely disparate. The most
recent taxonomic revision concluded that P. fergusi is the only valid
species and that the other nominal species are junior subjective
synonyms of this taxon. This proposal was based on the interpretation
that anatomical differences between the nominal species could be
explained as a result of ontogenetic changes and/or post-mortem
deformation. The recent discoveries of multiple new South African
proterosuchid specimens provide an impetus to revisit their taxonomy.
Based upon a comprehensive re-examination of all known specimens, as
well as examination of other proterosuchid taxa in collections
(Continue reading)

Ben Creisler | 18 Oct 18:28 2014
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Microraptor aerodynamics and arboreal flight

Ben Creisler
bcreisler <at> gmail.com

In the new Biological Journal of the Linnean Society:

Colin Palmer (2014)
The aerodynamics of gliding flight and its application to the arboreal
flight of the Chinese feathered dinosaur Microraptor.
Biological Journal of the Linnean Society 113 (3): 828–835
Special Issue: Celebrating Dinosaur Island
DOI: 10.1111/bij.12328
http://onlinelibrary.wiley.com/doi/10.1111/bij.12328/abstract

The evolution of avian flight is contentious and while it is now well
established that modern birds are descended from theropod dinosaurs
and that the presence of feathers predates the ability to fly, the
process of transition from feathered, ground based dinosaurs to their
feathered, flight capable descendants is less clear. While the
evolutionary and behavioural aspects have been considered in detail,
much less attention has been paid to the morphologies required to
sustain flight, even in the simple case of gliding flight – the likely
locomotory mode of the Chinese feathered dinosaur, Microraptor. Basic
aerodynamic principles are used to define the minimum requirements for
flight in terms of the necessary flight surfaces and flight stability.
The results are applied to the interpretation of wind tunnel tests on
a full scale model of the Chinese feathered dinosaur, Microraptor and
show that complex aerodynamic surfaces offer no clear advantages for
gliding flight in an arboreal environment.

(Continue reading)

Ben Creisler | 18 Oct 18:27 2014
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Dinosaurs on the Isle of Wight

Ben Creisler
bcreisler <at> gmail.com

In the new special issue of Biological Journal of the Linnean Society:

H. S. Torrens (2014)
The Isle of Wight and its crucial role in the ‘invention’ of dinosaurs.
Biological Journal of the Linnean Society 113 (3): 664–676
Special Issue: Celebrating Dinosaur Island
DOI: 10.1111/bij.12341
http://onlinelibrary.wiley.com/doi/10.1111/bij.12341/abstract

Dinosaurs were 'invented' in April 1842. Any history, before this,
must separate periods of pre-history. The first covers the period
before 1824 (when the first dinosaur genus Megalosaurus was
described). Here the Isle of Wight discloses a forgotten pioneer in
natural history, the stone mason/sculptor James Hay (c. 1748–1821) who
may well have included, by 1818, such dino-to-be material in his
remarkable Portsmouth museum. This was described on his death as ‘the
best private collection in the kingdom’. Sadly, his material is lost,
and no accurate diagnosis is possible. The second period extends from
1824 to 1842. The significant figure here is the Russia and East
Indies merchant James Vine (1774–1837), who first revealed how
Iguanodon bones occurred in abundance in the Island's south-west
coastal outcrops. One, between September 1841 and April 1842, revealed
to Richard Owen his long-sought fossil sacrum of an Iguanodon. This
was in the private London museum of the political radical W. D. Saull
(1783–1855). The discovery of this single fossil enabled Owen to
‘invent’ dinosaurs. He later wrote of this historic specimen how ‘the
characters of the order Dinosauria were mainly founded on this
(Continue reading)

Ben Creisler | 18 Oct 18:24 2014
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New birds from China: Eopengornis (enantiornithine genus) + Jeholornis curvipes (basal species)

Ben Creisler
bcreisler <at> gmail.com

In the new issue of Biological Journal of the Linnean Society devoted
to the Isle of Wight:

Ulysse Lefèvre, Dongyu Hu, François Escuillié, Gareth Dyke andPascal
Godefroit (2014)
A new long-tailed basal bird from the Lower Cretaceous of north-eastern China.
Biological Journal of the Linnean Society 113 (3): 790–804
Special Issue: Celebrating Dinosaur Island
DOI: 10.1111/bij.12343
http://onlinelibrary.wiley.com/doi/10.1111/bij.12343/abstract

A new basal Avialae, Jeholornis curvipes sp. nov., from the Yixian
Formation (Lower Cretaceous) of Liaoning Province (north-eastern
China) is described. A revision of long-tailed birds from China and a
phylogenetic analysis of basal Avialae suggest that Jeholornithiformes
were paraphyletic, with Jixiangornis orientalis being the sister-taxon
of pygostylia. The phylogenetic analysis also recovered that the tail
reduction is a unique event in the evolution of birds. Jeholornis
species were cursorial, nonperching, and seed-eating birds. © 2014 The
Linnean Society of London, Biological Journal of the Linnean Society,
2014, 113, 790–804.

***
Xiaoli Wang, Jingmai K. O'Connor, Xiaoting Zheng, Min Wang, Han Hu and
Zhonghe Zhou (2014)
Insights into the evolution of rachis dominated tail feathers from a
new basal enantiornithine (Aves: Ornithothoraces).
(Continue reading)

Ben Creisler | 18 Oct 17:39 2014
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Sauropod tracks in Brazil being eroded by hydroelectric project

Ben Creisler
bcreisler <at> gmail.com

A new online paper:

S.D.E. Valais , C.R. Candeiro, L.F. Tavares, Y.M. Alves & C. Cruvinel (2014)
Current situation of the ichnological locality of São Domingos from
the Corda Formation (Lower Cretaceous), northern Tocantins state,
Brazil.
Journal of South American Earth Sciences (advance online publication)
DOI: 10.1016/j.jsames.2014.09.023
http://www.sciencedirect.com/science/article/pii/S0895981114001357

Highlights

The São Domingos site are being eroded by the Hydroelectric Power
Plant do Estreito.
São Domingos tracks are related to basal sauropod or macronarians, or
diplodocoids.
The trackways are considered into the Parabrontopodus-like category.
These tracks are the only vertebrate record from the Early Cretaceous
Corda Formation.

Abstract

In the 80´s, Leonardi treated the presence of a vertebrate
ichnological locality from the Barremian Corda Formation, Parnaíba
Basin, on the left bank of the Tocantins river, near of the São
Domingos town, Itaguatins, State of Tocantins, Brazil. Originally, the
record was composed of at least seven in situ trackways, accounting
(Continue reading)

Ben Creisler | 18 Oct 17:35 2014
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Doratodon (notosuchian) as Gondwanan faunal link in Late Cretaceous of Europe

Ben Creisler
bcreisler <at> gmail.com

A new online paper:

Márton Rabi & Nóra Sebők (2014)
A revised Eurogondwana model: Late Cretaceous notosuchian
crocodyliforms and other vertebrate taxa suggest the retention of
episodic faunal links between Europe and Gondwana during most of the
Cretaceous.
Gondwana Research (advance online publication)
DOI: 10.1016/j.gr.2014.09.015
http://www.sciencedirect.com/science/article/pii/S1342937X14002913

Highlights

We find strong support for Gondwanan affinity in a Cretaceous European
crocodyliform.
We criticize the recently proposed “Eurogondwana” biogeographic model.
Episodic faunal interlinks characterized Europe and Africa in the Cretaceous.
The Gondwanan influence on Europe did not cease completely after the
Hauterivian.

Abstract

We describe new remains of the enigmatic Late Cretaceous crocodyliform
Doratodon carcharidens coming from the Santonian Csehbánya Formation
of Hungary. The material includes isolated upper and lower jaw
elements and teeth that represent the earliest occurrence of this
genus. Previous reports of Doratodon restricted the range of this
(Continue reading)


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