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Race to New Papers Mountain
Great heaping gobs of new papers to list...apologies if any of these are
Perrichot, V., and Giradr, V. 2009. A unique piece of amber and the complexity
of ancient forest ecosystems. Palaios 24(3):137-139. doi: 10.2110/palo.2009.S02.
Bader, K.S., Hasiotis, S.T., and Martin, L.D. 2009. Application of forensic
science techniques to trace fossils on dinosaur bones from a quarry in the
Upper Jurassic Morrison Formation, northeastern Wyoming. Palaios 24(3):140-158.
ABSTRACT: Trace fossils on sauropod skeletons from a quarry in fluvial deposits
of the Morrison Formation, Wyoming, are used to reconstruct the taphonomic
history of the dinosaur bone accumulation. Shallow pits; rosettes;
hemispherical pits; thin, curvilinear, branching grooves; and U- to V-shaped
linear grooves make up trace fossils found on sauropod skeletons. The traces
were interpreted by comparisons to traces on modern bone. Rosettes are circular
rings of modified bone and are likely an early stage in the production of
shallow pits. They are interpreted as pupation chambers constructed in dried
flesh in contact with sauropod bone. Hemispherical pits are circular with a
U-shaped cross section and interpreted as dermestid pupation chambers completed
in sauropod bone. Thin, curvilinear, branching grooves are semicircular in
cross section, form irregular dendritic or looping patterns, and are
interpreted as root etchings. U- to V-shaped linear grooves are interpreted as
theropod or crocodilian bite marks. Skeletal articulation and condition and
distribution of bone modification traces suggest the skeletons accumulated at
this site over no more than 3.5 years, with the bulk of the skeletons
contributed during the dry season in the final 3â6 months. Carcasses went
through all stages of decompositionâincluding the dry stage, represented by
shallow pits, rosettes, and hemispherical pits. Vertebrate scavengers and
necrophagous arthropods fed on the carcasses during all decomposition stages
prior to burial of the assemblage.
Dodson, P. 2009. Darwin and the dinosaurs. American Paleontologist 17(1):33-36.
Doube, M., Conroy, A.W., Christiansen, P., Hutchinson, J.R., and Shefelbine, S.
2009. Three-dimenstional geometric analysis of felid limb bone allometry. PLoS
ONE 4(3):e4742. doi: 10.1371/journal.pone.0004742.
Studies of bone allometry typically use simple measurements taken in a small
number of locations per bone; often the midshaft diameter or joint surface area
is compared to body mass or bone length. However, bones must fulfil multiple
roles simultaneously with minimum cost to the animal while meeting the
structural requirements imposed by behaviour and locomotion, and not exceeding
its capacity for adaptation and repair. We use entire bone volumes from the
forelimbs and hindlimbs of Felidae (cats) to investigate regional complexities
in bone allometry.
Computed tomographic (CT) images (16435 slices in 116 stacks) were made of 9
limb bones from each of 13 individuals of 9 feline species ranging in size from
domestic cat (Felis catus) to tiger (Panthera tigris). Eleven geometric
parameters were calculated for every CT slice and scaling exponents calculated
at 5% increments along the entire length of each bone. Three-dimensional
moments of inertia were calculated for each bone volume, and spherical radii
were measured in the glenoid cavity, humeral head and femoral head. Allometry
of the midshaft, moments of inertia and joint radii were determined. Allometry
was highly variable and related to local bone function, with joint surfaces and
muscle attachment sites generally showing stronger positive allometry than the
Examining whole bones revealed that bone allometry is strongly affected by
regional variations in bone function, presumably through mechanical effects on
bone modelling. Bone's phenotypic plasticity may be an advantage during rapid
evolutionary divergence by allowing exploitation of the full size range that a
morphotype can occupy. Felids show bone allometry rather than postural change
across their size range, unlike similar-sized animals.
Consoli, C.P., and Stilwell, J.D. 2009. Late Cretaceous marine reptiles
(Elasmosauridae and Mosasauridae) of the Chatham Islands, New Zealand.
Cretaceous Research. doi: 10.1016/j.cretres.2009.02.009.
ABSTRACT: A new marine reptile record for the Upper Cretaceous of the Chatham
Islands is described from the Takatika Grit. Incomplete mosasaur and plesiosaur
remains represent the first record of marine reptiles from the Chatham Islands
and wider New Zealand. Present among the myriad bones are elasmosaurid
plesiosaurs and mosasaurine mosasaurs. This assemblage is comparable to the New
Zealand marine reptile record and represents apex predators that flourished in
a zone of upwelling in a Late Cretaceous southern high-latitude ecosystem.
Clemente, C.J., Thompson, G.G., and Withers, P.C. 2009. Evolutionary
relationships of sprint speed in Australian varanid lizards. Journal of
Zoology. doi: 10.1111/j.1469-7998.2009.00559.x.
ABSTRACT: Ecomorphological studies often seek to link morphology and
performance to relevant ecological characteristics. Varanid lizards are unique
in that species can vary in body size by almost four orders of magnitude within
a single genus, and a question of considerable interest is whether similar
ecomorphological relationships exist when constraints on body size are reduced.
We studied sprint speed in relation to size, shape and ecology for 18 species
of varanid lizards. Maximal speed scaled positively with mass0.166 using least
squares regression, and mass0.21 using reduced major-axis regression. However,
a curvilinear trend better described this relationship, suggesting an optimal
mass of 2.83 kg with respect to speed. Including data for the komodo dragon
Varanus komodoensis moves the optimum mass to 2.23 kg. We use this relationship
to predict the sprint speed of the Komodo's giant extinct relative Varanus
(Megalania) prisca to be 2.6â3 m sâ1 similar to that of extant freshwater
crocodiles Crocodylus johnstoni. When differences in speed were compared to
ecological characteristics, species from open habitats were significantly
faster than species from semi-open or closed habitat types, and remained so
after correction for size and phylogeny. Thus, despite large variation in body
size, varanids appear to share similar associations between performance and
ecology as seen in other lizard groups. Varanids did, however, differ in
morphological relationships with sprint speed. Differences in relative speed
were not related to relative hindlimb length, as is commonly reported for other
lizard groups. Instead, size-free forefoot length was negatively related to
speed as was the size-free thoraxâabdomen length. While shorter forefeet were
thought to be an adaptation to burrowing, and thus open habitats, rather than
speed per se, the reduction in the thoraxâabdomen length may have significant
advantages to increasing speed. Biomechanical models predicting this advantage
are discussed in relation to !
Rich, T.H., Vickers-Rich, P., Flannery, T.F., Kear, B.P., Cantrill, D.J.,
Komarower, P., Kool, L., Pickering, D., Trusler, P., Morton, S., van Klaveren,
N., and Fitzgerald, E.M.G. 2009. An Australian multitubercular and its
palaeobiogeographic implications. Acta Palaeontologica Polonica 54(1):1-6.
ABSTRACT: A dentary fragment containing a tiny left plagiaulacoid fourth lower
premolar from the Early Cretaceous (Aptian) of Victoria provides the first
evidence of the Multituberculata from Australia. This unique specimen
represents a new genus and species, Corriebaatar marywaltersae, and is placed
in a new family, Corriebaataridae. The Australian fossil, together with meagre
records of multituberculates from South America, Africa, and Madagascar,
reinforces the view that Multituberculata had a cosmopolitan distribution
during the Mesozoic, with dispersal into eastern Gondwana probably occurring
prior to enforcement of climatic barriers (indicated by marked differentiation
in regional floras) in the Early Cretaceous.
Butler, R.J., and Sullivan, R.M. 2009. The phylogenetic position of the
ornithischian dinosaur Stenopelix valdensis from the Lower Cretaceous of
Germany: implications for the early fossil record of Pachycephalosauria. Acta
Palaeontologica Polonica 54(1):21-34.
ABSTRACT: The holotype of Stenopelix valdensis is the most completely known
dinosaur specimen from the âWealdenâ (Lower Cretaceous) of northwestern
Germany, but its phylogenetic position has remained highly controversial. Most
recent authors have suggested affinities with the ornithischian clade
Marginocephalia, and most commonly to the marginocephalian subclade
Pachycephalosauria. A pachycephalosaurian identity would make Stenopelix the
only confirmed preâLate Cretaceous member of this clade, breaking up an
extensive ghost lineage which extends to the inferred origin of
Pachycephalosauria in the MiddleâLate Jurassic. Based upon reâexamination
of the holotype we here review the characters that have previously been used to
assign Stenopelix to either Pachycephalosauria or Ceratopsia. All of these
characters are problematic, being based upon inaccurate anatomical
interpretations, or having more widespread distributions within Ornithischia
than previously realised. We conclude that although the overall anatomy of
Stenopelix is consistent with marginocephalian affinities, there is
insufficient evidence to support referral to either Pachycephalosauria or
Ceratopsia; we consider Stenopelix ?Marginocephalia. A brief review indicates
that there is no compelling fossil evidence for pachycephalosaurs prior to the
Barrett, P.M., Butler, R.J., Wang, X.-L., and Xu, X. 2009. Cranial anatomy of
the iguanodontoid ornithopod Jinzhousaurus yangi from the Lower Cretaceous
Yixian Formation of China. Acta Palaeontologica Polonica 54(1):35-48.
ABSTRACT: The Yixian Formation (Lower Cretaceous) of Liaoning Province, China,
is justifiably famous for its exceptionally preserved fauna, which includes a
remarkable diversity of nonâavian dinosaurs. Here, we provide the first
detailed description of the cranial skeleton of the iguanodontian ornithopod
Jinzhousaurus yangi. Many previously unrecorded features have been recognised,
permitting a new and more robust diagnosis for this taxon, which is based on a
suite of autapomorphic features. Jinzhousaurus and an unnamed sauropod
represent the largest, but some of the least abundant, animals in the Jehol
Biota, a situation that contrasts with many other Lower Cretaceous faunas in
which large dinosaurs are common faunal components. This rarity may be due to
either palaeoenvironmental constraints or taphonomic bias, although it is not
possible to choose between these alternatives on the basis of current data.
Hirasawa, T. 2009. The ligamental scar in the costovertebral articulation of
the tyrannosaurid dinosaurs. Acta Palaeontologica Polonica 54(1):49-59.
ABSTRACT: The costovertebral articulation is integral to constrain the thoracic
kinematics and to infer the breathing mechanism in the respect with costal
aspiration. However, the structure of the costovertebral articulation in
nonâavian theropods has not been studied in great detail before. This study
highlights the Tyrannosauridae, which is represented by numerous complete
specimens. Costovertebral articulations of ten tyrannosaurid specimens,
including two nearly inâsitu articulated fossils, were investigated and
compared with those in extant Archosauria. For extant archosaurs, dissections
were conducted to rationalize the soft tissue anatomy in tyrannosaurids. This
study shows that the rib articulates ventrally or posteroventrally with the
distal end of the corresponding vertebral transverse process in the
tyrannosaurid ribcage. A ligament (ligamentum costotransversarium) can be
reconstructed to connect the rib tuberculum to the transverse process in each
articulation. The scar for lig. costotransversarium is recognizable in many
theropod skeletons, and this rugosity can be used to identify the rotational
axis for the rib. This result provides a cornerstone for exploring the
evolution of the ribcage and breathing mechanisms across the theropod lineage
leading to birds.
Diedrich, C. 2009. The vertebrates of the Anisian/Ladinian boundary (Middle
Triassic) from Bissendorf (NW Germany) and their contribution to the anatomy,
palaeoecology, and palaeobiogeography of the Germanic Basin reptiles.
Palaeogeography, Palaeoclimatology, Palaeoecology 273(1-2):1-16. doi:
ABSTRACT: Systematically excavated bones are described from Bissendorf
(OsnabrÃcker Bergland, north-western Germany). The bone bed in the compressus
zone of the Ceratitenschichten (MeiÃner Fm, Upper Muschelkalk,
Anisian/Ladinian boundary, Middle Triassic) was dated by ceratites.
Sedimentologically, it is a bioclastic rudstone built mainly from Coenothyris
vulgaris brachiopods, which were heavily compressed into a 3 mm thin layer.
Parts of the bone bed and the following 15 cm of autochthonous mud were
partially eroded synsedimentary by the compressus storm event. The material of
the not-rich bone bed in the Germanic Upper Muschelkalk consists of isolated
teeth or fin spines from five well-known shark species: Hybodus longiconus
Agassiz, 1843, Acrodus lateralis Agassiz, 1837, Acrodus gaillardoti Agassiz,
1837, Palaeobates angustissimus Agassiz, 1838 and Polyacrodus polycyphus
Agassiz, 1837. Teeth and scales from the teleosteans Gyrolepis sp, Dollopterus
sp., Colobodus maximus, Quenstedt, 1835, C. frequens, Dames [Dames, W., 1888.
Die Ganoiden des Deutschen Muschelkalkes. Palaeontologische Abhandlungen 4,
133â180] and Saurichthys sp. have been proved. Found were mostly vertebra
centra and ribs, but also teeth and some other postcranial bones from the small
pachypleurosaurs Anarosaurus sp. as well as mostly Neusticosaurus sp. These
originated from adult and juvenile animals which indicates the primary habitat
and populations of this region. Large marine nothosaur reptiles found include
Nothosaurus cf. mirabilis MÃnster, 1834, and N. giganteus MÃnster, 1834.
Proof of two placodonts is given thanks to Placodus gigas Agassiz, 1833 and
Cyamodus sp. Finally, a tooth from the terrestrial lepidosaur Tanystrophaeus
longibardicus (Bassani, 1866) is the northerly most sample found. The recorded
fauna is well-known with complete skeletons of the described species from the
northern Tethys (Mte. San Giorgio, Switzerland). The reptile skeletons are
presented here in reconstruction. The bone bed composition in Bissen!
in the younger and more terrestrial mixed as well as the age difference in bone
beds of northern (enodis/posseckeri zone) and southern Germany (dorsoplanus
zone). At Bissendorf, only nearly complete marine vertebrates occur within the
maximum high stand. High marine ichthyosaurs seem to be absent, indicating a
shallow marine position in the western Germanic Basin.
Vullo, R., BernÃrdez, E., and Buscalioni, A.D. 2009. Vertebrates from the
middle?âlate Cenomanian La CabaÃa Formation (Asturias, northern Spain):
Palaeoenvironmental and palaeobiogeographic implications. Palaeogeography,
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2009.03.004.
ABSTRACT: The Asturian La CabaÃa Formation, middle?âlate Cenomanian in age,
has yielded a rich and diverse assemblage of vertebrate microremains. The fauna
consists of both marine and continental forms, including chimaeroids, various
selachians and actinopterygians, chelonians, crocodilians, plesiosaurs,
pterosaurs, sauropod dinosaurs, and marine squamates. This mixed assemblage of
autochthonous (coastal) and allochthonous (continental) elements comes mainly
from a transgressive lag occurring near the base of the formation. It also
contains some remains which are probably reworked from older middle Cenomanian
deposits. Palaeontological, taphonomic, and sedimentologic data indicate a
shallow platform and marine lagoon, with addition of some continental elements.
A comparison with the late Cenomanian vertebrate assemblage of Charentes
(southwestern France) shows numerous similarities between both areas. Some
taxa, only known from Asturias and Charentes (e.g., the aigialosaur
Carentonosaurus), suggest that the opening Bay of Biscay may have constituted a
palaeobiogeographic area characterized by endemism during the mid-Cretaceous.
Ruban, D.A., Zerfass, H., and Pugatchev, V.I. 2009. Triassic synthems of
southern South America (southwestern Gondwana) and the Western Caucasus (the
northern Neotethys), and global tracing of their boundaries. Journal of South
American Earth Sciences. doi: 10.1016/j.jsames.2009.03.003.
ABSTRACT: Global tracing of the key surfaces of Triassic deposits may
contribute significantly to the understanding of the common patterns in their
accumulation. We attempt to define synthems â disconformity-bounded
sedimentary complexes â in the Triassic successions of southern South America
(southwestern Gondwana, Brazil and Argentina) and the Western Caucasus (the
northern Neotethys, Russia), and then to trace their boundaries in the adjacent
regions and globally. In southern South America, a number of synthems have been
recognized - the Cuyo Basin: the RÄÂo Mendoza-Cerro de las Cabras Synthem
(Olenekian-Ladinian) and the Potrerillos-Cacheuta-RÄÂo Blanco Synthem
(Carnian-Rhaetian); the Ischigualasto Basin: the Ischichuca-Los Rastros Synthem
(Anisian-Ladinian) and the Ischigualasto-Los Colorados Synthem
(Carnian-Rhaetian); the Chaco-ParanÃ Basin: the Sanga do Cabral Synthem
(Induan), the Santa Maria 1 Synthem (Ladinian), the Santa Maria 2 Synthem
(Carnian), and the Caturrita Synthem (Norian); western Argentina: the Talampaya
Synthem (Lower Triassic) and the Tarjados Synthem (Olenekian?). In the Western
Caucasus, three common synthems have been distinguished: WC-1 (Induan-Anisian),
WC-2 (uppermost Anisian-Carnian), and WC-3 (Norian-lower Rhaetian). The lower
boundary of WC-1 corresponds to a hiatus whose duration seems to be shorter
than previously postulated. The synthem boundaries common to southwestern
Gondwana and the Western Caucasus lie close to the base and top of the
Triassic. The Lower Triassic, Ladinian, and Upper Triassic disconformities are
traced within the studied basins of southern South America, and the first two
are also established in South Africa. The Upper Triassic disconformity is only
traced within the entire Caucasus, whereas all synthem boundaries established
in the Western Caucasus are traced partly within Europe. In general, the
synthem boundaries recognized in southern South America and the Western
Caucasus are correlated to the global Triassic sequence boundaries and!
falls. Although regional peculiarities are superimposed on the appearance of
global events in the Triassic synthem architecture, the successful global
tracing suggests that planetary-scale mechanisms of synthem formation existed
and that they were active in regions dominated by both marine and non-marine
O'Connor, J.K., Wang, X., Chiappe, L.M., Gao, C., Meng, Q., Cheng, X., and Liu,
J. 2009. Phylogenetic support for a specialized clade of Cretaceous
enantiornithine birds with information from a new species. Journal of
Vertebrate Paleontology 29(1):188-204.
ABSTRACT: A new species of enantiornithine bird from the Lower Cretaceous
Yixian Formation of northeastern China is reported. The new taxon, Shanweiniao
cooperorum, possesses several enantiornithine synapomorphies as well as the
elongate rostral morphology (rostrum equal to or exceeding 60% the total length
of the skull) of the Chinese early Cretaceous enantiornithines, Longipteryx
chaoyangensis and Longirostravis hani. The discovery of this new specimen
highlights the existence of a diverse clade of trophically specialized
enantiornithines, Longipterygidae, for which we present phylogenetic support in
a new comprehensive cladistic analysis of Mesozoic birds. Shanweiniao provides
new information on the anatomy of longipterygids, and preserves a rectricial
morphology previously unknown to enantiornithines, with at least four tail
feathers closely arranged. This supports the hypothesis that enantiornithines
were strong fliers and adds to the diversity of known tail morphologies of
these Cretaceous birds.
Kellner, A.W.A., Pinheiro, A.E.P., Azevedo, S.A.K., Henriques, D.D.R., de
Carvalho, L.B., and Oliveira, G.R. 2009. A new crocodyliform from the
AlcÃntara Formation (Cenomanian), Cajual Island, Brazil. Zootaxa 2030:49-58.
ABSTRACT: A new mesoeucrocodylian (Crocodyliformes) is described from the Laje
do Coringa site, earliest Late Cretaceous (early Cenomanian) of the SÃo LuÃs
Basin, northeastern Brazil. Due to the likely hetorodonty indicated by distinct
alveoli shapes, Coringasuchus anisodontis gen. et sp. nov. is tentatively
referred to the Notosuchia and distinguished from other members of this clade
by the presence of obliquely implanted teeth with the main axis directed
anterolingually-toposterolabially and the presence of alveoli that are
distinctively raised above the level of the dorsal margin of the dentary. The
material further confirms the interpretation that the fossil concentration of
the Laje do Coringa site is the result of multiple reworking events from
previous deposits, but the degree of time-averaging was possibly higher than
Vargas, A.O., and Wagner, G.P. 2009. Frame-shifts of digit identity in bird
evolution and Cyclopamine-treated wings. Evolution & Development 11(2):163-169.
ABSTRACT: A highly conserved spatio-temporal pattern of cartilage formation
reveals that the digits of the bird wing develop from positions that become
digits 2, 3, and 4 in other amniotes. However, the morphology of the digits of
early birds like Archaeopteryx corresponds to that of digits 1, 2, and 3 of
other archosaurs. A hypothesis is that a homeotic "frame-shift" occurred, such
that in the bird wing, digits 1, 2, and 3 develop from the embryological
positions of digits 2, 3, and 4. Experimental homeotic transformations of
single digits are well-documented, but frame-shifts of more than one digit are
not. We investigated the pattern of cartilage formation in the development of
Cyclopamine-treated wings. When Cyclopamine was applied between stages 18 and
21, morphologies that normally develop from positions 2 and 3 developed from
positions 3 and 4. The serial shift of digit identity toward posterior confirms
a mechanistic possibility that was previously inferred from the evolutionary
history of birds.
Schmitt, S. 2009. Haeckel, un darwinien allemand? Comptes Rendus Biologies
332(2-3):110-118. doi: 10.1016/j.crvi.2008.07.006.
ABSTRACT: German biologist Ernst Haeckel (1834â1919) is often considered the
most renowned Darwinian in his country since, as early as 1862, he declared
that he accepted the conclusions Darwin had reached three years before in On
the Origin of Species, and afterwards, he continuously proclaimed himself a
supporter of the English naturalist and championed the evolutionary theory.
Nevertheless, if we examine carefully his books, in particular his General
Morphology (1866), we can see that he carries on a tradition very far from
Darwin's thoughts. In spite of his acceptance of the idea of natural selection,
that he establishes as an argument for materialism, he adopts, indeed, a
conception of evolution that is, in some respects, rather close to Lamarck's
views. He is, thus, a good example of the ambiguities of the reception of
Darwinism in Germany in the second part of the 19th century.
de RicqlÃs, A., and Padian, K. 2009. Quelques apports Ã la thÃorie de
l'Ãvolution, de la "SynthÃse orthodoxe" Ã la "Super synthÃse Ãvo-dÃvo?
1970-2009: un point de vue. Comptes Rendus Palevol 8(2-3):341-364. doi:
ABSTRACT: The âModern Synthesisâ of evolutionary biology coalesced and
revitalized evolutionary theory beginning in the 1930s. It stressed the
explanatory power of natural selection and gradual change to account for the
processes that govern natural populations today, as well as patterns in the
history of life. In the past 40 years, the synthesis has been challenged on
various fronts ranging from paleontology to developmental biology, systematics,
biogeography, and molecular and developmental biology. Several of its central
propositions have been modified and expanded as a result. How well the
synthesis continues to be effective will depend on its continued ability to
test its central propositions and the efficacy of its central mechanisms,
particularly on the basis of new evidence from emerging fields of study.
Badlangana, N.L., Adams, J.W., and Manger, P.R. 2009. The giraffe (Giraffa
camelopardalis) cervical vertebral column: a heuristic example in understanding
evolutionary processes? Zoological Journal of the Linnean Society
155(3):736-757. doi: 10.1111/j.1096-3642.2008.00458.x.
ABSTRACT: The current study considers the osteological morphology of the
giraffe (Giraffa camelopardalis) vertebral column, with emphasis on evaluating
both the adaptive and constraining features compared with other ungulates as a
heuristic example in understanding evolutionary processes. Vertebral columns of
giraffes varying in age from calf to adult were studied in order to understand
the potential evolutionary scenarios that might have led to the modern
phenotype. Data from the giraffe sample were then compared with the results
from several other ungulate species, including the okapi and two species of
camelids that also have visibly elongated necks. Our results show that the
elongated neck of the modern giraffe appears to specifically result from
evolutionary changes affecting the seven cervical vertebrae, independent of the
remainder of the vertebral column. The cervical vertebrae comprise over half of
the length of the total vertebral column in the giraffe. The increases in
cervical vertebrae lengths also appear to be allometrically constrained, with
alterations in the overall length of the neck resulting from the elongation of
the entire cervical series, rather than from a single vertebra or subset of
vertebrae. We place our results in the context of hypotheses concerning the
origin and evolution of the giraffe neck, and the evolution of long necks in a
White, M.A. 2009. The subarctometatarsus: intermediate metatarsus architecture
demonstrating the evolution of the arctometatarsus and advanced agility in
theropod dinosaurs. Alcheringa 33(1):1-21. doi: 10.1080/03115510802618193.
ABSTRACT: The subarctometatarsus is a plesiomorphic form of arctometatarsus.
Five individual subarctometatarsalian specimens are examined in this study
including Microraptor gui, Sinornithosaurus millenii, Sinovenator changii,
Sinovenator sp. and Sinornithoides youngi. Bivariate analysis illustrates a
closer relationship between subarctometatarsalians and small theropods
possessing the plesiomorphic theropod metatarsus (e.g. Compsognathidae and
Archaeopteryx). Reduced major axis (RMA) analysis supported this conclusion but
also indicates a distinct statistical difference between the three categories
of theropod metatarsus. Additionally, development of the subarctometatarsus is
inferred to have been linked to advanced cursoriality as implicated for the
arctometatarsus. Structural similarity between the subarctometatarsus and the
arctometatarsus portrays a common mechanical function of being able to
withstand the forces of high impact with the substrate. Phylogenetic analysis
reveals five independent origins of the arctometatarsus.
Zhang, Z.-Q., Gao, C., Meng, Q., Liu, J., Hou, L., and Zheng, G. 2009.
Diversification in an Early Cretaceous avian genus: evidence from a new species
of Confuciusornis from China. Journal of Ornithology. doi:
ABSTRACT: A new species of Confuciusornis, the oldest known beaked bird, is
erected based on a nearly complete fossil from the Early Cretaceous Yixian
Formation of western Liaoning, northeast China. C. feducciai is the largest and
shows the highest ratio of the forelimb to the hindlimb among all known species
of Confuciusornis. The skeletal qualitative autapomorphies, including a
V-shaped furcula, a rectangular deltopectoral crest, the absence of an oval
foramen at the proximal end of the humerus, the very slender alular digit, a
relatively much longer ischium which is two-thirds the length of the pubis, and
the morphology of sternum, strongly suggest the new specimen is a valid
distinctive taxon. Detailed comparison with other described species provides
sound evidence for diversification in the Early Cretaceous avian genus
Confuciusornis. Anatomical features suggest an arboreal habit of the new bird.
Sullivan, C., Hone, D.W.E., Cope, T.D., Liu, Y., and Liu, J. 2009. A new
occurrence of small theropod tracks in the Houcheng (Tuchengzi) Formation of
Hebei Province, China. Vertebrata PalAsiatica 47(1):35-52.
ABSTRACT: Small theropod footprints have been known from the
Jurassic-Cretaceous boundary strata of northeastern China for several decades,
although these ichnofossils have been overshadowed by the feathered dinosaurs
and other body fossils from the Yixian Formation of Liaoning Province. This
paper describes a sample of several theropod footprints from a coarse fluvial
deposit at Nanshuangmiao, in the lowermost Houcheng (Tuchengzi) Formation of
Hebei Province. The Nanshuangmiao tracks exhibit a tridactyl, pachydactylous
morphology corresponding to classic "brontozoid" ichnites (Grallator,
Anchisauripus and Eubrontes) from the Lower Jurassic of the United States of
America. Although many brontozoid tracks from the roughly equivalent Tuchengzi
of Liaoning have been previously assigned to the small ichnogenus Grallator, as
G. ssatoi, the Nanshuangmiao tracks are larger (up to 28.8 cm total length) and
are probably referable to Anchisauripus. The Nanshuangmiao tracks were most
likely produced by small theropods travelling in a group. Of the abundant
theropod taxa known from the Yixian Formation of Liaoning, the small
oviraptorosaur Caudipteryx is the most plausible trackmaker, but this
interpretation remains uncertain because of a lack of diagnostic features in
the tracks and because of the temporal and geographic gap between the Houcheng
of Hebei and the Yixian of Liaoning.
Evans, S.E., and Wang, Y. 2009. A long-limbed lizard from the Upper
Jurassic/Lower Cretaceous of Daohugou, Ningcheng, Nei Mongol, China. Vertebrata
ABSTRACT: Lizards are now relatively well known from the Jehol Group of
northeastern China, seven taxa having been named from the group or equivalent
horizons. Here we describe a lizard specimen from a fossil horizon at Daohugou
of Ningcheng, Nei Mongol, which predates the Yixian Formation of the Jehol
Group. This is the second lizard from this locality. Comparisons with
ontogenetic series of modern lizards show that the new Daohugou lizard is a
juvenile. The specimen is notable in having a slender body and relatively long
limbs and extremities. Even allowing for immaturity, its proportions differ
markedly from those of previously described Jehol Biota lizards. Comparison
with modern lizards suggests the new Daohugou lizard may have been at least
partly scansorial. Its phylogenetic placement is problematic given its
immaturity and preservation, but skull characters and vertebral number preclude
attribution to Iguania and it may be a scleroglossan.
Wu, X.-C., Cheng, Y.-N., Sato, T., and Shan, H.-Y. 2009. Miodentosaurus brevis
Cheng et al., 2007 (Diapsida: Thalattosauria): its postcranial skeleton and
phylogenetic relationships. Vertebrata PalAsiatica 47(1):1-20.
ABSTRACT: Miodentosaurus brevis was first established on the basis of the skull
and mandible of a fairly preserved skeleton from the Triassic Falang Formation,
Guanling area, Guizhou Province. The description of the postcranial skeleton
reveals that M. brevis is also distinct in the morphology of its girdle
elements, such as the coracoid with a small embayment just posterior to the
glenoid, interclavicle becoming much narrower posteriorly than anteriorly, and
the ilium having a dorsal blade with a expanded distal end. With a further
preparation, some of the skull anatomy are redescribed. Based on new
information from both skull and the postcranial skeleton, the diagnosis of the
taxon is revised. A phylogenetic analysis suggests that M. brevis is an
askeptosauroid, closely related to Askeptosaurus from Switzerland and Italy on
the basis of two unequivocal synapomorphies, a retroarticular process broader
than long and a reduced deltopectoral crest in the humerus.
Pole, M., and Vajda, V. 2009. A new terrestrial Cretaceous-Paleogene site in
New Zealandâturnover in macroflora confirmed by palynology. Cretaceous
Research. doi: 10.1016/j.cretres.2009.02.007.
ABSTRACT: A fluvial sequence near Cave Stream (north of Castle Hill Village,
central Canterbury), New Zealand, contains organically-preserved plant
macrofossils (cuticles). The almost ubiquitous presence of Araucariaceae
macrofossils in the lower part of the section and their stratigraphic
disappearance roughly coincident with the appearance of the angiosperm leaf
Dryandra comptoniaefolia and conifer taxa only known elsewhere from sediments
of Paleogene age, indicates that the section spans the Cretaceous-Paleogene
(K-T) boundary. This was subsequently confirmed by a palynological study that
demonstrated the disappearance of Late Cretaceous index species within the
investigated exposure. The sequence supports the pattern recognized elsewhere
in New Zealand where Araucariaceae macrofossils either disappear or become very
rare in end-Cretaceous and the leaf Dryandra comptoniaefolia is an important
component in the early Cenozoic. The Cave Stream K-T boundary is one of the
very few in the world with organically-preserved plant macrofossils and
confirms the dramatic turnover in macroflora, which is known from North America.
Gastaldo, R.A., Neveling, J., Clark, C.K., and Newbury, S.S. 2009. The
terrestrial Permian-Triassic boundary event bed is a nonevent. Geology
37(3):199-202. doi: 10.1130/G25255A.1.
ABSTRACT: A unique isochronous interval in the Karoo Basin, South Africa,
previously has been interpreted to postdate vertebrate extinction at the
Permian-Triassic boundary in the Bethulie area, Lootsberg Pass, and elsewhere.
It is demonstrated that the laminated beds, or laminites, in the Bethulie
region are stratigraphically indistinct. The heterolithic interval exposed on
the Heldenmoed farm is ~8 m below the Bethel farm section, <1 km away. At
Lootsberg Pass, the laminated interval is below the Permian-Triassic boundary
as defined by vertebrate biostratigraphy, rather than overlying it. Hence, this
interval, critical to models of end-Permian mass extinction, is neither
isochronous across the basin nor unique. Rather, the lithofacies represents
avulsion channel-fill deposits within aggradational landscapes. South African
models for the response of terrestrial ecosystems to the perturbation in the
marine realm require critical reevaluation.
Andreotti, B., FourriÃre, A., Ould-Kaddour, F., Murray, B., and Claudin, P.
2009. Giant aeolian dune size determined by the average depth of the
atmospheric boundary layer. Nature 457:1120-1123. doi: 10.1038/nature07787.
ABSTRACT: Depending on the wind regime, sand dunes exhibit linear,
crescent-shaped or star-like forms resulting from the interaction between dune
morphology and sand transport. Small-scale dunes form by destabilization of the
sand bed with a wavelength (a few tens of metres) determined by the sand
transport saturation length. The mechanisms controlling the formation of giant
dunes, and in particular accounting for their typical time and length scales,
have remained unknown. Using a combination of field measurements and
aerodynamic calculations, we show here that the growth of aeolian giant dunes,
ascribed to the nonlinear interaction between small-scale superimposed dunes,
is limited by the confinement of the flow within the atmospheric boundary
layer. Aeolian giant dunes and river dunes form by similar processes, with the
thermal inversion layer that caps the convective boundary layer in the
atmosphere acting analogously to the water surface in rivers. In both cases,
the bed topography excites surface waves on the interface that in turn modify
the near-bed flow velocity. This mechanism is a stabilizing process that
prevents the scale of the pattern from coarsening beyond the resonant
condition. Our results can explain the mean spacing of aeolian giant dunes
ranging from 300 m in coastal terrestrial deserts to 3.5 km. We propose that
our findings could serve as a starting point for the modelling of long-term
evolution of desert landscapes under specific wind regimes.
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
"Life is the art of drawing
sufficient conclusions from
-- Samuel Butler