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Protoceratopsid track with skeleton and other new refs



From: Ben Creisler
bh480@scn.org


A number of new papers with a few not directly about dinosaurs but of
interest:

Grzegorz Niedzwiedzki, Tomasz Singer, Gerard D. Gierlinski, and Martin G.
Lockley (2011)
A protoceratopsid skeleton with an associated track from the Upper
Cretaceous of Mongolia. 
Cretaceous Research (advance online publication)
doi:10.1016/j.cretres.2011.07.001
http://www.sciencedirect.com/science/article/pii/S0195667111000966

Abstract
The Djadokhta Formation of the Gobi Desert is known for the number and
diversity of dinosaur and other vertebrate bones and skeletons found there,
but only theropod, hadrosaur and supposed ankylosaurid footprints have been
reported from this stratum. Dinosaur footprints are also noted from the
Nemegt Formation, and occur as typical dinosaur track acumulations
(tracksites). An articulated protoceratopsid skeleton - specimen ZPAL Mg
D-II/3 - was collected by the Polish-Mongolian Expedition of 1965 from the
Djadokhta Formation of Flaming Cliffs in Mongolia. Recently, the natural
cast of a tetradactyl digitigrade footprint was found underneath the pelvic
girdle while the skeleton and matrix were being prepared. This is possibly
the first find of a dinosaur track in close association with an articulated
skeleton. Although Protoceratops is an extremely common dinosaur in
Mongolia, its footprints have never previously been reported from the Late
Cretaceous of the Gobi Desert.

***
Diego Castanera, José Luis Barco, Ignacio Díaz-Martínez, Jesús Herrero
Gascón,  Félix Pérez-Lorente,  and José Ignacio Canudo (2011) 
New evidence of a herd of titanosauriform sauropods from the Lower
Berriasian of the Iberian Range (Spain). 
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online
publication)
doi:10.1016/j.palaeo.2011.07.015
http://www.sciencedirect.com/science/article/pii/S0031018211003981

Abstract
A study of the undescribed part of the Las Cerradicas tracksite in Galve
(Teruel, Spain) has revealed 6 trackways made by small sauropods showing
gregarious behaviour (parallel trackways). Las Cerradicas is located
towards the top of the Villar del Arzobispo Formation (early Berriasian).
The wide-gauge condition, the manus-pes distance, the kidney-shaped
morphology of the manus, and the subtriangular morphology of the pes (with
a big digit I that swells medially and a narrow heel oriented
posterolaterally) suggest that the sauropods in question are more similar
to Sauropodichnus giganteus than to any other sauropod ichnotaxa. Some of
the features point to the titanosauriforms as the best candidates to be the
trackmakers. Recent work in bone histology, the differences with respect to
other Iberian tracksites of similar age, and the differences with respect
to other sauropod herds of the track record, do not allow us to establish
whether the sauropods were juvenile or dwarfs. The sauropod skeletal record
and other large sauropod footprints in the Villar del Arzobispo Formation
could tip the scales in favour of the first hypothesis.

***
Mototaka Saneyoshi, Mahito Watabe, Shigeru Suzuki and Khishigjav
Tsogtbaatar (2011)
Trace fossils on dinosaur bones from Upper Cretaceous eolian deposits in
Mongolia: Taphonomic interpretation of paleoecosystems in ancient desert
environments.
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online
publication)
doi:10.1016/j.palaeo.2011.07.024
http://www.sciencedirect.com/science/article/pii/S003101821100407X

Abstract
The formation processes of trace fossils - including shallow to deep pits,
notches, borings (tunnels), and channels, particularly at the limb joints -
observed on the surfaces of Velociraptor, Protoceratops, ankylosaurid, and
Bagaceratops skeletons from Upper Cretaceous eolian deposits in the Gobi
desert, Mongolia were investigated. The median diameters of these
structures ranged from 5.25 to 7.68 mm. These structures were likely
created by insects scavenging on dinosaur carcasses. This interpretation is
corroborated by the presence of burrows of a size similar to the trace
fossils observed on the dinosaur bone surfaces at the same locality. Broad
borings (about 32 mm in diameter) created by small Mesozoic mammals have
also been discovered on the ribs and scapulae of a Protoceratops skeleton.
Dinosaur skeletons found at two localites, Tugrikin-Shireh and Khermeen
Tsav, and two formations, the Djadokhta Formation and Barun Goyot
Formation, exhibited the same type of damage to the limb joints. The high
frequency of trace fossils at the limb joints suggests that small animals
targeted the collagen in the joint cartilage of dried dinosaur carcasses as
a source of nitrogen, which was relatively scarce in the eolian
environments of the Gobi desert during the Late Cretaceous.

***

Jimmy A. McGuire and Robert Dudley  (2011)
The Biology of Gliding in Flying Lizards (Genus Draco) and their Fossil and
Extant Analogs. 
Integrative & Comparative Biology (advance online publication)
doi: 10.1093/icb/icr090 
http://icb.oxfordjournals.org/content/early/2011/07/28/icb.icr090.abstract

Abstract
The flying lizards of the genus Draco are among the most remarkable and
successful clades of gliding vertebrates. Here, we evaluate the evolution
of gliding in Draco and other lizards, describe the suite of morphological
innovations that characterize Draco, discuss the ecological context of
gliding in this genus, describe functions of their patagial membranes that
are not related to gliding, and summarize the interspecific allometry of
the Draco gliding apparatus, as well as the corresponding consequences for
their now empirically quantified gliding performance. Several fossil
reptilian lineages had morphologies similar to that of modern Draco, with
patagial membranes supported by elongated ribs or rib-like dermal
structures. Using Draco's snout-vent length/mass relationships, we provide
improved estimates of wing loading for three of these fossil gliders
(Icarosaurus seifkeri, Kuehneosaurus sp., Coelurosauravus elivensis) and
then estimate absolute gliding performance for each taxon by extrapolating
from Draco's wing loading/glide performance relationship. We find that I.
seifkeri likely represented the best nonflapping terrestrial vertebrate
glider yet described, whereas the larger Kuehneosaurus and Coelurosauravus
probably required high descent velocities to achieve sufficient lift for
gliding, with commensurately greater height loss with each glide. 

***
Gerald Mayr (2011)
Cenozoic mystery birds ? on the phylogenetic affinities of bony-toothed
birds (Pelagornithidae).
Zoologica Scripta (advance online publication)
DOI: 10.1111/j.1463-6409.2011.00484.x
http://onlinelibrary.wiley.com/doi/10.1111/j.1463-6409.2011.00484.x/abstract

Abstract
The extinct Cenozoic bony-toothed birds (Pelagornithidae) are characterized
by the occurrence of unique spiky projections of the osseous jaws and are
among the most distinctive neornithine taxa. Earlier authors considered
these marine birds to be most closely related to ?Pelecaniformes? or
Procellariiformes, but recent phylogenetic analyses resulted in a sister
group relationship to Anseriformes. This latter hypothesis was, however,
coupled with a non-monophyly of galloanserine or even neognathous birds,
which is not supported by all other current analyses. The character
evidence for anseriform affinities of pelagornithids is thus reassessed,
and it is detailed that the alleged apomorphies cannot be upheld.
Pelagornithids lack some key apomorphies of galloanserine birds, and
analysis of 107 anatomical characters did not support anseriform
affinities, but resulted in a sister group relationship between
Pelagornithidae and Galloanseres. By retaining a monophyletic Galloanseres,
this result is in better accordance with widely acknowledged hypotheses on
the higher-level phylogeny of birds. The (Pelagornithidae + Galloanseres)
clade received, however, only weak bootstrap support, and some characters,
such as the presence of an open frontoparietal suture, may even support a
position of Pelagornithidae outside crown-group Neognathae.

***
Matthew G. Jackson & Richard W. Carlson (2011) 
An ancient recipe for flood-basalt genesis.
Nature (advance online publication)
doi:10.1038/nature10326 
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10326.html

Abstract
Large outpourings of basaltic lava have punctuated geological time, but the
mechanisms responsible for the generation of such extraordinary volumes of
melt are not well known1. Recent geochemical evidence suggests that an
early-formed reservoir may have survived in the Earth?s mantle for about
4.5 billion years (ref. 2), and melts of this reservoir contributed to the
flood basalt emplaced on Baffin Island about 60 million years ago. However,
the volume of this ancient mantle domain and whether it has contributed to
other flood basalts is not known. Here we show that basalts from the
largest volcanic event in geologic history--the Ontong Java plateau--also
exhibit the isotopic and trace element signatures proposed for the
early-Earth reservoir. Together with the Ontong Java plateau, we suggest
that six of the largest volcanic events that erupted in the past 250
million years derive from the oldest terrestrial mantle reservoir. The
association of these large volcanic events with an ancient primitive mantle
source suggests that its unique geochemical characteristics?it is both
hotter (it has greater abundances of the radioactive heat-producing
elements) and more fertile than depleted mantle reservoirs?may strongly
affect the generation of flood of flood basalts.






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