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New Papers in Rodanthe



Mateus, O., Overbeeke, M., and Rita, F. 2008. Dinosaur frauds, hoaxes and
'Frankensteins': how to distinguish fake and genuine vertebrate fossils.
Journal of Paleontological Techniques 2:1-5.

ABSTRACT: Dinosaurs and other fossils have been artificially enhanced, or
totally forged, to increase their commercial value. The most problematic
forgeries to detect are based on original fossils that are artificially
assembled. Several techniques are suggested for detecting hoaxes: detailed
visual examination, chemical analysis, Xray or CT-scan, and ultraviolet
light.
     It is recommended that museums and paleontological researchers do not
purchase and/or trade fossils lacking clear provenience information.
Exceptions to that general rule should be closely examined using techniques
described herein.

     (available free at
www.jpaleontologicaltechniques.org/pasta3/JPT%20N2/Pdf/JPT_n002_Jul.pdf)



Boutakiout, M., Hadri, M., Milhi, A., Nouri, J., Díaz-Martínez, I., and P
érez-Lorente, F. 2008. Icnitas terópodos y saurópodos del Bajociense en
Ifgh. (Norte de Msemrir. Alto Atlas Central. Marruecos). Geo-Temas
10:1249-1252.

ABSTRACT: In the Bajocian Hight Atlas calcareous beds of Ifgh (norhern
Msemerir) are dinosaur footprints reported to theropod and sauropod
ichnites. The described neightbouring sites are in Arhbalou and Taoudaat (at
NE) and Adrar-n-Ouglagal (SW),in addition to another non studied in the same
Msemerir area. The site has peculiar trackways and footprints of theropod
type (semiplantigrades alternated with digitigrades) and irregular groups of
sauropod footprints too in some of wich manus only marks are mainly. Among
other things its probably that sauropods were swimming and there are
evidences in order to say that one of the dinosaurs had semiplantigrade
optional gait. Dinosaurs made his traks in an algae laminated bed which is
traversed and deformed by their feet. Therefore, although there are so much
direct structures, most of the outline footprints are undertracks and not
true footprints.



Gasca, J.M., Moreno-Azanza, M., and Canudo, J.I. 2008. Dientes de
dinosaurios terópodos espinosáuridos de la Formación El Castellar (Cretá
cico Inferior, Teruel). Palaeontologica Nova. SEPAZ.




Harshman, J., Braun, E.L., Braun, M.J., Huddleston, C.J., Bowie, R.C.K.,
Chojnowski, J.L., Hackett, S.J., Han, K.-L., Kimball, R.T., Marks, B.D.,
Miglia, K.J., Moore, W.S., Reddy, S., Sheldon, F.H., Steadman, D.W.,
Steppan, S.J., Witt, C.C., and Yuri, T. 2008. Phylogenomic evidence for
multiple losses of flight in ratite birds. Proceedings of the National
Academy of Sciences 105(36):13462-13467. doi: 10.1073/pnas.0803242105.

ABSTRACT: Ratites (ostriches, emus, rheas, cassowaries, and kiwis) are
large, flightless birds that have long fascinated biologists. Their current
distribution on isolated southern land masses is believed to reflect the
breakup of the paleocontinent of Gondwana. The prevailing view is that
ratites are monophyletic, with the flighted tinamous as their sister group,
suggesting a single loss of flight in the common ancestry of ratites.
However, phylogenetic analyses of 20 unlinked nuclear genes reveal a
genome-wide signal that unequivocally places tinamous within ratites, making
ratites polyphyletic and suggesting multiple losses of flight. Phenomena
that can mislead phylogenetic analyses, including long branch attraction,
base compositional bias, discordance between gene trees and species trees,
and sequence alignment errors, have been eliminated as explanations for this
result. The most plausible hypothesis requires at least three losses of
flight and explains the many morphological and behavioral similarities among
ratites by parallel or convergent evolution. Finally, this phylogeny demands
fundamental reconsideration of proposals that relate ratite evolution to
continental drift.





Seiler, W.M., and Chan, M.A. 2008. A wet interdune dinosaur trampled surface
in the Jurassic Navajo Sandstone, Coyote Buttes, Arizona: rare preservation
of multiple track types and tail traces. Palaios 23(10):700-710. doi:
10.2110/palo.2007.p07-082r.

ABSTRACT: A distinctive, disturbed surface with numerous soft-sediment
impressions occurs within a wet interdune interval of Jurassic Navajo
Sandstone at the Coyote Buttes along the Arizona-Utah border. These
high-density impressions are interpreted as footprints that comprise a
dinosaur trampled surface. This surface displays an unusual combination of
multiple overlapping track types and sizes, distinct to modified footprint
features that include claws and toes and rare tail traces. The trampled
surface covers 3000 m2 with an average density of 12 impressions/m2 in its
main extent. Although modern water collection and biofilms typical of
weathering potholes or pits are superimposed on this surface, the primary
origin of the impression features are trace fossil structures formed prior
to lithification. Four criteria distinguish the impressions as vertebrate in
origin: (1) large―up to several tens of centimeters―repeating identifiable
foot morphologies; (2) impression floors surrounded by soft-sediment
marginal ridges; (3) impressions that are rarely flat and are typically
oriented at an angle into the sediment (media) and indicate a clear
direction of travel; and (4) multiple in situ ichnofossils on a moist
interdune surface that resulted in soft-sediment deformation. At least three
ichnogenera―cf. Eubrontes, cf. Anchisauripus, cf. Grallator ― and the
tracks attributed to a sauropodomorph appear as regular to asymmetric
penetrations into the media with digitate features, commonly accompanied by
soft-sediment marginal ridges of displaced sand preserved in the sandstone.
The trampled surface provides paleoecologic and paleoclimatologic proxies
that suggest a pluvial climate shift likely induced groundwater saturation
of an eolian interdune that attracted dinosaurs to the area. The trampled
surface provides valuable data for refining ecologic and climatic
sensitivities recorded in Early Jurassic eolian deposits.






Manning, P.L., Ott, C., and Falkingham, P.L. 2008. A probable tyrannosaurid
track from the Hell Creek Formation (Upper Cretaceous), Montana, United
States. Palaios 23(10):645-647. doi: 10.2110/palo.2008.p08-030r.

ABSTRACT: Large theropod tracks have previously been attributed to
Tyrannosaurus rex. Most identifications however, have not been supported by
either clear comparison with T. rex osteology or the stratigraphic position
of the track. There is a conspicuous absence of tracks in the Upper
Cretaceous (Maastrichtian) Hell Creek, Lance, Scollard, Frenchman, and
Denver Formations (Lancian, North American Land Mammal Age), where T. rex
body fossils have been found. A large tridactyl track is described here from
the Hell Creek Formation of Carter County, Montana, United States. This find
constitutes the first record of a large theropod track from the Hell Creek
Formation, which could have potentially been made by T. rex or another large
theropod, based on the track morphology and stratigraphic position.





Farke, A.A. 2008. Frontal sinuses and head-butting in goats: a finite
element analysis. Journal of Experimental Biology 211(19):3085-3094. doi:
10.1242/jeb.019042.

ABSTRACT: Frontal sinuses in goats and other mammals have been hypothesized
to function as shock absorbers, protecting the brain from blows during
intraspecific combat. Furthermore, sinuses are thought to form through
removal of `structurally unnecessary' bone. These hypotheses were tested
using finite element modeling. Three-dimensional models of domesticated goat
(Capra hircus) skulls were constructed, with variable frontal bone and
frontal sinus morphology, and loaded to simulate various head-butting
behaviors. In general, models with sinuses experienced higher strain energy
values (a proxy for shock absorption) than did models with unvaulted frontal
bones, and the latter often had higher magnitudes than models with solid
vaulted frontal bones. Furthermore, vaulted frontal bones did not reduce
magnitudes of principal strain on the surface of the endocranial cavity
relative to models with unvaulted frontal bones under most loading
conditions. Thus, these results were only partially consistent with sinuses,
or the bone that walls the sinuses, acting as shock absorbers. It is
hypothesized that the keratinous horn sheaths and cranial sutures are
probably more important for absorbing blows to the head. Models with sinuses
did exhibit a more `efficient' distribution of stresses, as visualized by
histograms in which models with solid frontal bones had numerous unloaded
elements. This is consistent with the hypothesis that sinuses result at
least in part from the removal of mechanically unnecessary bone.





Codron, D., Brink, J.S., Rossouw, L., Clauss, M., Codron, J., Lee-Thorp,
J.A., and Sponheimer, M. 2008. Functional differentiation of African grazing
ruminants: an example of specialized adaptations to very small changes in
diet. Biological Journal of the Linnean Society 94(4):755-764. doi:
10.1111/j.1095-8312.2008.01028.x.

ABSTRACT: We assess whether interspecific differences in craniodental
morphology within a single ruminant feeding guild, the grazers, represent
anatomical adaptations to subtle differences in diet. Differences in
craniodental anatomy follow a distinct taxonomic pattern that is paralleled
by dietary niche differentiation recorded in species' stable carbon (δ13C)
and nitrogen isotope (δ15N) compositions, strongly supporting a hypothesis
for functional divergence within the grazers. We propose that the
evolutionary origin of grazers were multifold; at least two and up to four
different types of grazing can be discerned within the 11 taxa studied here
alone. However, correspondence between craniodental adaptations and isotopic
differences across species are not found when only δ13C data are considered
(i.e. morphological differences do not reflect varying proportions of C3
browse to C4 grass consumed). This implies that alternate anatomical
adaptations to grazing are not related to differences between variable
(part-time browsing) and obligate grazers, as previously predicted. Rather,
anatomical differences correlate strongly with changes in δ15N, which we
infer to reflect functional responses to changes in diet quality associated
with the degree of feeding selectivity and short-, medium-, or tall-grass
grazing.





Sadleir, R.W., and Makovicky, P.J. 2008. Cranial shape and correlated
characters in crocodilian evolution. Journal of Evolutionary Biology. doi:
10.1111/j.1420-9101.2008.01602.x.

ABSTRACT: Crocodilians show a high degree of cranial variation and
convergence throughout their 80 million-year fossil record that complicates
their phylogenetic reconstruction. Conflicting phylogenetic results from
different data partitions and character homoplasies typify crocodilian
phylogeny, and differences between molecular and morphological phylogenetic
hypotheses are believed to be associated with the slender-snout skull shape
of Gavialis gangeticus and Tomistoma schlegelii. Slender-snout skulls are
one of five identified eusuchian cranial ecomorph shape categories (ESCs)
thought to reflect functional or ecological specialization. This paper
tested the effect of transitions among general, blunt and slender ESCs on
cranial character-state distributions in phylogeny using the concentrated
changes test. In addition, 'tree-free' character compatibility analysis of
character independence was conducted on the morphological character matrix
to determine if character correlations are observed independent of specific
tree topologies. Results suggest cranial ESCs do affect cranial
character-state gains in phylogeny. Concentrated changes identify a broad
suite of character-state changes that significantly correlate with
transitions to slender, general and blunt ESCs on morphological, molecular
and combined-data tree topologies, but numbers of correlated characters for
each category differ according to topology. Character compatibility analysis
results do not mirror the concentrated changes test results and reflect
hierarchically distributed support throughout the data. As cranial ESCs
affect character-state transitions, it is possible that nonphylogenetic
variables could affect inferences of crocodilian phylogeny by affecting
cranial morphology.




Zorina, S.O., Dzyuba, O.S., Shurygin, B.N., and Ruban, D.A. 2008. How global
are the Jurassic-Cretaceous unconformities? Terra Nova 20(5):341-346. doi:
10.1111/j.1365-3121.2008.00826.x.

ABSTRACT: The reality of the global-scale sedimentation breaks remains
controversial. A compilation of data on the Jurassic?Cretaceous
unconformities in a number of regions with different tectonic settings and
character of sedimentation, where new or updated stratigraphic frameworks
are established, permits their correlation. Unconformities from three large
reference regions, including North America, the Gulf of Mexico, and Western
Europe, were also considered. The unconformities, which encompass the
Jurassic-Cretaceous, the Lower?Upper Cretaceous and the Cretaceous?
Palaeogene transitions are of global extent. Other remarkable unconformities
traced within many regions at the base of the Jurassic and at the Santonian
?Campanian transition are not known from reference regions. A correlation
of the Jurassic?Cretaceous global-scale sedimentation breaks and eustatic
curves is quite uncertain. Therefore, definition of global sequences will
not be possible until eustatic changes are clarified. Activity of mantle
plumes is among the likely causes of the documented unconformities.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/

"I have made this letter longer
than usual because I lack the
time to make it shorter."
                      -- Blaise Pascal