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The Back-up New Papers



Xu, X., Zheng, X., and You, H. 2010. Exceptional dinosaur fossils show
ontogenetic development of early feathers. Nature 464:1338-1341. doi:
10.1038/nature08965.

ABSTRACT: Recent discoveries of feathered dinosaur specimens have greatly
improved our understanding of the origin and early evolution of feathers,
but little information is available on the ontogenetic development of early
feathers. Here we describe an early-juvenile specimen and a late-juvenile
specimen, both referable to the oviraptorosaur Similicaudipteryx, recovered
from the Lower Cretaceous Yixian Formation of western Liaoning, China. The
two specimens have strikingly different remiges and rectrices, suggesting
that a radical morphological change occurred during feather development, as
is the case for modern feathers. However, both the remiges and the rectrices
are proximally ribbon-like in the younger specimen but fully pennaceous in
the older specimen, a pattern not known in any modern bird. In combination
with the wide distribution of proximally ribbon-like pennaceous feathers and
elongate broad filamentous feathers among extinct theropods, this find
suggests that early feathers were developmentally more diverse than modern
ones and that some developmental features, and the resultant morphotypes,
have been lost in feather evolution.





Kim, B.S., and Huh, M. 2010. Analysis of the acceleration phase of a
theropod dinosaur based on a Cretaceous trackway from Korea.
Palaeogeography, Palaeoclimatology, Palaeoecology. doi:
10.1016/j.palaeo.2010.04.020.

ABSTRACT: Well-preserved trackways of carnivorous dinosaurs belonging to
small-sized theropods have been reported from the Cretaceous Neungju Group
in South Korea. The site at Hwasun Seoyu-ri Quarry represents the most
extensive and diverse theropod trackway ichnofauna in South Korea. Among
them, one theropod trackway is unique in that it demonstrates that theropods
were able to increase stride lengths to reach maximum speed, during the
running phase. Fossilized track evidence of the acceleration ability of
dinosaurs is scant. Despite this, the evidence shown in our findings
suggests a theropod running near the limit of its capabilities and shows
evidence of a temporary acceleration of speed while running.






Führ Dal' Bó, P.F., Basilici, G., and Simões Angelica, R. 2010. Factors of
paleosol formation in a Late Cretaceous eolian sand sheet paleoenvironment,
Marília Formation, Southeastern Brazil. Palaeogeography, Palaeoclimatology,
Palaeoecology. doi: 10.1016/j.palaeo.2010.04.021.

ABSTRACT: The Marília Formation, which crops out in southeastern Brazil, is
interpreted as a Late Cretaceous eolian sand sheet area. The sedimentary
succession, ca 110 m thick, is characterized by alternating strata of eolian
deposits and paleosols. The paleosols constitute more than 66% of the
thickness, and are an important element in the interpretation of the
paleoenvironmental controlling factors which affected the soil formation in
this eolian sand sheet. In this paper six paleosol profiles are described
and assigned to two pedotypes: Itaja and Apore. The Itaja pedotype is
constituted of a sequence of five superimposed polygenetic profiles which
show different phases of clay illuviation and carbonate precipitation, and
it has been classified as Aridisol. The Apore pedotype overlies the Itaja
pedotype. This pedotype shows an increase in leaching, CIA-K ratios,
reddening, and illuvial clay features in respect to Itaja, and has been
classified as Alfisol. The analysis of the factors which controlled the soil
formation revealed that both pedotypes formed on a stable landscape probably
covered by a community of low stature plants, in which the soils had
sufficient time to develop very mature profiles. The changes in soil-forming
processes were driven principally by variations in available soil moisture
from precipitation. Using depth-to-carbonate functions from Bk and CIA-K
proxy from Bt horizons of the Itaja pedotype, mean annual precipitation
(MAP) estimates range from 240 to 1078 mm/year, respectively. These
contrasting climatic conditions resulted in the superimposition of arid or
semi-arid with more humid climates and determined the considerable change in
the pedogenic features, with many horizons showing the interlacing of
calcite and clay features. In the Apore pedotype CIA-K proxy from Bt
horizons estimates that averaged MAP was around 900 mm/year, and the
prevalent humid conditions can be attested by soil properties and abundance
and depth of root traces. Our results show that the diversity in pedotypes
is mainly attributed to differences in paleoclimatic conditions during
Maastrichtian time, and that eolian sedimentation was restricted to periods
of harsh arid conditions, as in semi-arid climates, with MAP estimates
around 240 mm/year, the formation of soils with well developed calcic
horizons was possible.






Vickaryous, M.K., and Hall, B.K. 2010. Comparative development of the
crocodylian interclavicle and avian furcula, with comments on the homology
of dermal elements in the pectoral apparatus. Journal of Experimental
Zoology 314B:196-207. doi: 10.1002/jez.b.21326.

ABSTRACT: The pectoral apparatus (shoulder girdle plus sternum) of amniotes
plesiomorphically includes an unpaired element of dermal origin. In
crocodylians, lepidosaurs, and nontherian synapsids (monotremes and their
ancestors) this element is identified as the interclavicle, in Testudines
(turtles and tortoises) as the entoplastron, and in Aves as the furcula. We
investigated embryonic development of the interclavicle in Alligator
mississippiensis (American alligator) and of the furcula in Gallus gallus
(domestic chicken). The interclavicle and furcula are among the first
skeletal elements to ossify, beginning at Ferguson stage 19 (Alligator) and
Hamburger and Hamilton stage 33 (Gallus). Both elements: occupy a similar
mid-ventral position within the pectoral apparatus; develop from paired
(bilateral) cell condensations; never coexist at anytime during ontogeny or
in the adult; and undergo intramembranous (i.e., direct) ossification. For
both the interclavicle and the furcula, the initial onset of ossification is
concomitant with mineralization of elements of the dermatocranium, and
occurs in advance of mineralization of the replacement bones (e.g., scapula,
metacoracoid) of the pectoral apparatus. Shortly after the initiation of
ossification the paired condensations of both elements fuse. For each of
Alligator and Gallus, only one pair of skeletogenic condensations is present
during embryonic development. Based on these data and a review of the
evolution and development of dermal elements in the pectoral apparatus, we
conclude that the interclavicle is equally parsimonious as a homolog of the
furcula.








Haddoumi, H., Charrière, A., and Mojon, P.-O. 2010. Stratigraphie et
sédimentologie des Couches rouges continentales du Jurassique-Crétacé du
Haut Atlas central (Maroc): implications paléogéographiques et géodynamiques
Geobios. doi: doi:10.1016/j.geobios.2010.01.001.

ABSTRACT: In several synclines of the central High Atlas, the ?Redbeds?
following the closure of the marine Tethyan Atlasic trough during the Middle
Jurassic are constituted by three successive formations or units of
continental deposits dated recently with biostratigraphical elements. Some
micropaleontological markers, mainly charophytes and ostracods, allow to
precise the stratigraphy in agreement with a Bathonian-?Callovian assignment
for the lower unit (Guettioua Formation) and in dating the middle and upper
units. The Upper Jurassic, mainly the Kimmeridgian, is developed in the
lower part of the middle unit (Iouaridene Formation). The Barremian has been
recognized in this middle unit and in the upper unit (Jbel Sidal Formation).
The Jurassic/Cretaceous boundary is thus delimited for the first time with
micropaleontological data. These new data are very significant for the
Atlasic history during the Mesozoic. The basaltic flows inserted in the
continental Jurassic-Cretaceous deposits of the central High Atlas result
from two separate events in the Middle Jurassic and in the Barremian. The
tectogenesis in the basins is characterized by a polyphase process including
notably a synsedimentary tectonic activity conspicuous in the Barremian. The
evidence of marine to brackish intercalations allows moreover to date the
first Cretaceous transgressive event on the NW boundary of the High Atlas
during the Lower Barremian and to consider an Atlantic paleogeographical
interaction. SW margin of the Tethyan trough in the Lower and Middle
Jurassic, the central High Atlas is merged with the margin of the central
Atlantic Ocean during the Lower Cretaceous.






Mannion, P.D., Upchurch, P., Carrano, M.T., and Barrett, P.M. 2010. Testing
the effect of the rock record on diversity: a multidisciplinary approach to
elucidating the generic richness of sauropodomorph dinosaurs through time.
Biological Reviews. doi: 10.1111/j.1469-185X.2010.00139.x.

ABSTRACT: The accurate reconstruction of palaeobiodiversity patterns is
central to a detailed understanding of the macroevolutionary history of a
group of organisms. However, there is increasing evidence that diversity
patterns observed directly from the fossil record are strongly influenced by
fluctuations in the quality of our sampling of the rock record; thus, any
patterns we see may reflect sampling biases, rather than genuine biological
signals. Previous dinosaur diversity studies have suggested that
fluctuations in sauropodomorph palaeobiodiversity reflect genuine biological
signals, in comparison to theropods and ornithischians whose diversity seems
to be largely controlled by the rock record. Most previous diversity
analyses that have attempted to take into account the effects of sampling
biases have used only a single method or proxy: here we use a number of
techniques in order to elucidate diversity. A global database of all known
sauropodomorph body fossil occurrences (2024) was constructed. A taxic
diversity curve for all valid sauropodomorph genera was extracted from this
database and compared statistically with several sampling proxies (rock
outcrop area and dinosaur-bearing formations and collections), each of which
captures a different aspect of fossil record sampling. Phylogenetic
diversity estimates, residuals and sample-based rarefaction (including the
first attempt to capture 'cryptic' diversity in dinosaurs) were implemented
to investigate further the effects of sampling. After 'removal' of biases,
sauropodomorph diversity appears to be genuinely high in the Norian,
Pliensbachian?Toarcian, Bathonian?Callovian and Kimmeridgian?Tithonian (with
a small peak in the Aptian), whereas low diversity levels are recorded for
the Oxfordian and Berriasian?Barremian, with the Jurassic/Cretaceous
boundary seemingly representing a real diversity trough. Observed diversity
in the remaining Triassic?Jurassic stages appears to be largely driven by
sampling effort. Late Cretaceous diversity is difficult to elucidate and it
is possible that this interval remains relatively under-sampled. Despite its
distortion by sampling biases, much of sauropodomorph palaeobiodiversity can
be interpreted as a reflection of genuine biological signals, and
fluctuations in sea level may account for some of these diversity patterns.






Bordy, E.M., Sztanó, O., Rubidge, B.S., and Bumby, A. 2010. Early Triassic
vertebrate burrows from the Katberg Formation of the south-western Karoo
Basin, South Africa. Lethaia. doi: 10.1111/j.1502-3931.2010.00223.x.

ABSTRACT: Very large (~30?35 cm), uniform diameter cylindrical burrows were
found at two localities, ~100?110 m above Permo-Triassic boundary in the
fluvial Katberg Formation (main Karoo Basin, South Africa). Analysis of
their morphology and stratigraphical distribution allows us to improve both
the understanding of the ethology of burrowing, and also the reconstruction
of the earliest Triassic ecosystems. These burrows have a single opening
that leads, via a large, uniform diameter, semi-horizontal tunnel, to a
rounded terminus. These 3-m-long structures descend at angles of ~30° to a
maximum of 1.5 m depth. They are devoid of chambers, branching,
cross-cutting, coiling or spiralling. Filled with coarse sediments, some
have a <5-mm clay lining, and most have subtle indentations and various
scratch marks. These burrows were possibly excavated as resting, hiding or
aestivating shelters, and are tentatively attributed to dicynodonts (i.e.
Lystrosaurus murrayi and L. declivis). Data suggest that burrowing was
widespread after the P/Tr boundary event, when in this part of Gondwana,
dryland fluvial systems had large fluctuations in flow with extended
low-flow periods or drought punctuated by high-discharge periods. We
hypothesize that these constructed refuges played a role in the biodiversity
recovery and maintenance in the Early Triassic (Induan) ecosystem.





Paik, I.S., Kim, H.J., and Huh, M. 2010. Impressions of dinosaur skin from
the Cretaceous Haman Formation in Korea. Journal of Asian Earth Sciences.
doi: 10.1016/j.jseaes.2010.02.015.

ABSTRACT: The occurrences and features of two specimens of fossil dinosaur
skin from Cretaceous Haman formation in South Korea, including a new type of
skin texture (development of micropolygons within scales) are described here
for the first time, and several types of sedimentological aberrations of
inorganic origin that are similar in appearance to fossil skin and therefore
have the potential to be misidentified as fossil skin. The features and
origins of fossil dinosaur skin found in South Korea with those of a diverse
range of geological aberration structures resembling fossil skin are also
compared.
     It is interpreted that dry climate, the presence of torn skin, and
episodic sheetflood on an alluvial plain were related with the preservation
of the Haman skin fossils. The preservation condition of the Haman skin
fossils suggests that sheetflood deposits on a floodplain to mudflat
environment under dry climatic condition are potential candidates for
dinosaur skins to be found. The results of this study not only provide
additional information that is helpful in understanding dinosaur skin, but
also are useful in discriminating between true fossil skin and enigmatic
sedimentological aberration structures resembling skin.






Gangloff, R.A., and Fiorillo, A.R. 2010. Taphonomy and paleoecology of a
bonebed from the Prince Creek Formation, North Slope, Alaska. Palaios
25(5):299-317.

ABSTRACT: The late Campanian?Maastrichtian Liscomb Bonebed is the richest
source of dinosaur remains thus far documented in the polar regions. This
bed is formally defined herein and assigned to the upper part of the Prince
Creek Formation; the bonebed and several other organic-rich beds are part of
a 178 m sequence of fluvial and volcaniclastic deposits. The Liscomb Bonebed
is a mudstone rich in clay, comminuted plant remains, and palynomorphs with
a total organic carbon (TOC) of 6.80%?10.55%. It contains a multitaxic,
low-diversity, dinosaur assemblage, dominated by Edmontosaurus sp., which is
primarily represented by late juveniles. Four theropod taxa are almost
exclusively represented by isolated teeth. With >6000 specimens collected,
the assemblage is characterized by a Minimum Number of Individuals (MNI) of
36, dominance of Voorhies Groups I and II, and an underrepresentation of
teeth, skulls, and girdles. Bones are highly fragmented and exhibit low
weathering and abrasion indices. Bite marks occur on slightly more than 1%
of elements. The densest accumulations of bone are typically found in the
middle third of the bed with the largest bones at the bottom. The Liscomb
Bonebed assemblage resulted from mass mortality associated with overbank
floods that formed floodplain mires and ponds. Data from the current study
clearly establish the Alaskan Arctic as the year-round residence of a rich
dinosaur fauna and add further support to the hypotheses that even
high-latitude hadrosaurids were gregarious and formed social groups.






Smith, D.L., and Hayward, J.L. 2010. Bacterial decomposition of avian
eggshell: a taphonomic experiment. Palaios 25(5):318-326.

ABSTRACT: Dinosaurs, like modern birds, produced enormous quantities of
eggshell as part of the reproductive process. Sometimes this eggshell was
fossilized but most commonly was destroyed by weathering. The degree to
which bacteria may have contributed to this weathering process has not been
explored. In this study, fresh glaucous-winged gull (Larus glaucescens)
eggshell fragments were collected from the surface of a breeding colony in
Washington, sterilized, and buried in sterile soil. The soil surrounding
replicate experimental fragments was inoculated with a culture of one of
five species of soil bacteria isolated from other eggshell fragments
collected on the colony surface. Replicate control fragments received the
same treatment minus the bacteria. Weekly changes in protein concentration
and fragment mass, as well as in soil pH and calcium concentration, were
measured for experimental and control fragments over 10 weeks. The presence
of all five types of bacteria degraded the eggshell and produced corrosion
patterns similar to those seen in naturally weathered eggshell. On the basis
of the results we postulate that bacterial decomposition of the eggshell
protein matrix produces organic acids, which, in turn, dissolve the CaCO3 of
the shell. The dissolved CaCO3 and NH3 from protein degradation increase the
pH of the surrounding sediment. These results and interpretations are
discussed in view of dinosaur eggshell fossilization. This paper provides
the first evidence that bacteria significantly impact eggshell preservation.







Bourquin, S., Eschard, R., and Hamouche, B. 2010. High-resolution sequence
stratigraphy of Upper Triassic succession (Carnian - Rhaetian) of the
Zarzaitine outcrops (Algeria): a model of fluvio-lacustrine deposits Journal
of African Earth Sciences. doi: 10.1016/j.jafrearsci.2010.04.003.

ABSTRACT: The detailed facies analysis of the Zarzaitine outcrops (Illizi
Basin in the In Amenas area of Algeria) allows the depositional environment
of the Upper Triassic succession to be defined: braided rivers within an
arid and humid alluvial plain, low sinuosity rivers within a humid alluvial
plain, lake deposits and marginal sabkha. The description of the outcrops
helps to define three types of genetic units from a proximal to a distal
depositional environment: fluvial, fluvial-lacustrine and lacustrine. The
spatial and temporal evolutions of the genetic unit were characterised by
five specific stages from dry to humid climate conditions, inducing sediment
supply and lake-level variations. During the first two stages (stage 1 and
2) under a dry climate, the lake level was low and sediments mostly
by-passed and poorly preserved. During stages 3 and 4, an increase in
humidity and rainfall induced a rise in the lake-level and the development
of vegetation, as well as a decrease in the sediment supply, although the
sediment preservation were then at its maximum. The last stage (stage 5)
marked the beginning of a decrease in the humidity, the minimum of sediment
supply and the maximum of the lake level. Therefore, the recognition and the
description of genetic units within this fluvial-lacustrine environment help
to demonstrate the interaction between climate, sediment supply and
lake-level variation, at the scale of these units.
     Six stratigraphic cycles have been recognised in the vertically stacked
genetic units and can be grouped in three megacycles (denoted as I, II and
III). The first megacycle, attributed to Carnian to early Norian,
corresponds to the base of braided river systems with some ephemeral
channels developed in an arid environment where some aeolian deposits were
preserved. It evolved trough time to humid conditions favouring the
development of extensive floodplain, associated with hydromorphic soils, and
perennial lake environments. During the Carnian times and Norian, the
Zarzaitine area was not connected to the Berkine basin northward, a
Hercynian unconformity palaeorelief forming a drainage divide. According to
the directions of the palaeocurrents, the sediment provenances were mostly
from the southwest and the north. The connection with the Berkine basin only
occurred during the upper part of the megacycle II deposition, characterised
by fluvio-lacustrine environments. The maximum flooding of the megacycle I,
Norian in age, could be correlated with the early Norian maximum flooding
observed on the Saharan platform. The late Norian-Rhaetian second megacycle
was mostly a lacustrine environment associated with extensive floodplain,
with the development of a hydromorphic palaeosol with root imprints
attributed to a warm and humid climate. The maximum flooding episode of this
second megacycle could be attributed to the major marine trangression
recorded in Algeria, during the Rhaetian, and could be correlated with a
relative sea-level rise. A dolomitic level, attributed to sabkha
environments, marks the beginning of the retrogradational trend of the third
cycle, attributed to the Rhaetian-Liassic. The palaeocurrent of the upper
part of megacycle II and of the megacycle III were always oriented toward
the northeast, attesting that the relief was located to the southwest.






Vullo, R., and Néraudeau, D. 2010. Additional dinosaur teeth from the
Cenomanian (Late Cretaceous) of Charentes, southwestern France. Comptes
Rendus Palevol. doi: 10.1016/j.crpv.2010.03.001.

ABSTRACT: Some isolated teeth of theropod and sauropod dinosaurs from the
Cenomanian (Late Cretaceous) of Charentes are described. Two new teeth of
Troodontidae confirm the presence of this theropod family, previously based
on a single specimen. New dental morphotypes are recognized within
Dromaeosauridae and Brachiosauridae in comparison with those already known
from Charentes. Lastly, a very small tooth is tentatively assigned to an
embryonic or neonatal sauropod. The palaeobiogeographical history of
European hadrosauroids is briefly discussed. This history was probably more
complex than it appears, involving exchanges with both North America and
Asia as early as the mid-Cretaceous (Albian?Cenomanian).






Butler, R.J., Barrett, P.M., Penn, M.G., and Kenrick, P. 2010. Testing
coevolutionary hypotheses over geological timescales: interactions between
Cretaceous dinosaurs and plants. Biological Journal of the Linnean Society
100(1):1-15. doi: 10.1111/j.1095-8312.2010.01401.x.

ABSTRACT: Testing coevolutionary scenarios over extended geological
timescales is fraught with difficulties. Most tests rely on comparisons of
temporal variations in taxonomic diversity for the groups of interest:
however, this approach typically excludes spatiotemporal data. Here, we
apply a quantitative method that incorporates the spatiotemporal
distributions of the proposed coevolving groups using a Geographical
Information System. Distributional data for Cretaceous dinosaur and plant
groups were mapped onto palaeogeographical reconstructions in a series of
time-slices. Within each time-slice, palaeocontinental surfaces were divided
into a series of grids, each of which was scored as present, absent or
inapplicable (unsampled) for each group. Distributions were compared
statistically to determine whether the putative coevolving groups
co-occurred within grid squares more or less frequently than expected by
chance. Pairwise comparisons were made between herbivorous dinosaur clades
and major plant groups (e.g. cycads, angiosperms) on a global scale. Only
three nonrepeated associations of marginal significance were recovered,
demonstrating that, in general, current knowledge of the spatiotemporal
distributions of these groups provides little support for coevolutionary
hypotheses. The Geographical Information System methods used are readily
applicable to many other questions whose answers are reliant on a detailed
knowledge of organismal distributions in time and space.






Kokshenev, V.B., and Christiansen, P. 2010. Salient features in the
locomotion of proboscideans revealed via the differential scaling of limb
long bones. Biological Journal of the Linnean Society 100(1):16-29. doi:
10.1111/j.1095-8312.2010.01415.x.

ABSTRACT: The standard differential scaling of proportions in limb long
bones (length against circumference) was applied to a phylogenetically wide
sample of the Proboscidea, Elephantidae and the Asian (Elephas maximus) and
African (Loxodonta africana) elephants. In order to investigate allometric
patterns in proboscideans and terrestrial mammals with parasagittal limb
kinematics, the computed slopes between long bone lengths and circumferences
(slenderness exponents) were compared with published values for mammals, and
studied within a framework of the theoretical models of long bone scaling
under gravity and muscle forces. Limb bone allometry in E. maximus and the
Elephantidae is congruent with adaptation to bending and/or torsion induced
by muscular forces during fast locomotion, as in other mammals, whereas the
limb bones in L. africana appear to be adapted for coping with the
compressive forces of gravity. Hindlimb bones are therefore more compliant
than forelimb bones, and the resultant limb compliance gradient in extinct
and extant elephants, contrasting in sign to that of other mammals, is shown
to be a new important locomotory constraint preventing elephants from
achieving a full-body aerial phase during fast locomotion. Moreover, the
limb bone pattern of African elephants, indicating a noncritical bone stress
not increasing with increments in body weight, explains why their mean and
maximal body masses are usually above those for Asian elephants. Differences
in ecology may be responsible for the subtle differences observed in vivo
between African and Asian elephants, but they appear to be more pronounced
when revealed via mechanical patterns dictated by limb bone allometry.





Suteethorn, S., Le Loeuff, J., Buffetaut, E., and Suteethorn, V. 2010.
Description of topotypes of Phuwiangosaurus sirindhornae, a sauropod from
the Sao Khua Formation (Early Cretaceous) of Thailand, and their
phylogenetic implications. Neues Jahrbuch für Geologie und Paläontologie
Abhandlungen 256(1):109-121. doi: 10.1127/0077-7749/2010/0036.

ABSTRACT: The holotype of Phuwiangosaurus sirindhornae Martin, Buffetaut and
Suteethorn 1994, a 10 % complete sauropod skeleton, was excavated in the
early 1980s by a Thai-French expedition. In 1993, the site was re-opened and
yielded two additional vertebrae: one posterior dorsal and one proximal
caudal vertebra. On the basis of the size and shape of the vertebrae and the
absence of identical bones from the type locality, we conclude that these
vertebrae belong to the same individual as the holotype of P. sirindhornae
and consider them as topotypes. A phylogenetic analysis, which for the first
time includes recently described cranial and postcranial material, indicates
that Phuwiangosaurus  is a basal member of Titanosauriformes.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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 noticed even people who
claim everything is predestined, and
that we can do nothing to change it,
look before they cross the road."

                   -- Stephen Hawking

"Prediction is very difficult,
especially of the future."

                   -- Niels Bohr