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Canudo, J.I., Barco, J.L., Castanero, D., and Torcida Fernández-Baldor, F.
2010. New record of a sauropod in the Jurassic-Cretaceous transition of the
Iberian Peninsular (Spain): palaeobiogeographical implications.
Paläontologische Zeitschrift. doi: 10.1007/s12542-010-0057-x.
ABSTRACT: In recent decades a unique association of basal neosauropod and
turiasaur sauropods has been described from the Jurassic-Cretaceous
transition of Spain. In this context, a sauropod femur from the
Tithonian-Berriasian is studied for the first time. The femur in question is
an isolated specimen, recovered from the Tera Group in Tera (Soria). It
displays a unique mosaic of derived characters as yet undescribed in femora
of the Upper Jurassic and Lower Cretaceous of Spain. A prominent lateral
bulge, high eccentricity, and a lateromedially flattened proximal end link
the femur from Tera with Titanosauriformes. Moreover, it presents a
significant distal projection of the tibial condyle, a character observed in
Asiatic Titanosauriformes of the Lower Cretaceous. The femur from Tera adds
a fifth sauropod taxon to the Tithonian-Berriasian of Spain, and, for the
first time, a representative of Titanosauriformes.
Méndez, A.H., Novas, F.E., and Chatterjee, S. 2010. An abelisaurid humerus
from the Upper Cretaceous of India Paläontologische Zeitschrift. doi:
10.1007/s12542-010-0055-z.
ABSTRACT: The Lameta Formation (Upper Cretaceous, Maastrichtian) of India
has yielded abundant fossils of abelisaurid theropods, including bones from
the cranium, vertebral column, pectoral and pelvic girdles, and hindlimb.
However, the forelimbs of Indian abelisaurids remain unknown. Here we
describe an abelisaurid humerus from exposure of the Lameta Formation near
the village of Rahioli in northwestern India. This new material exhibits
derived traits that are distinctive of Abelisauridae, for example an
articular head that is hemispherical in proximal view, thus establishing the
specimen as the first abelisaurid humerus from India.
Boyer, D.M., Prasad, G.V.R., Krause, D.W., Godinot, M., Goswami, A., Verma,
O., and Flynn, L.J. 2010. New postcrania of Deccanolestes from the Late
Cretaceous of India and their bearing on the evolutionary and biogeographic
history of euarchontan mammals Naturwissenschaften. doi:
10.1007/s00114-010-0648-0.
ABSTRACT: Extant species of the supraordinal mammal clade Euarchonta belong
to the orders Primates, Scandentia, or Dermoptera. The fossil record of
euarchontans suggests that they underwent their initial radiation during the
Paleocene (65-55 Ma ago) in North America, Eurasia, and Africa. The time and
place of origin is poorly resolved due to lack of definitive fossils of
euarchontan stem taxa. We describe a fragmentary humerus and two fragmentary
ulnae from the latest Cretaceous of India that bear significantly on this
issue. The fossils are tentatively referred to Deccanolestes cf. hislopi due
to their small size and the fact that Deccanolestes is the only eutherian
dental taxon to have been recovered from the same locality. The new fossils
are used to evaluate the existing behavioral hypothesis that Deccanolestes
was arboreal, and the competing phylogenetic hypotheses that Deccanolestes
is a stem eutherian versus a stem euarchontan. The humerus resembles those
of euarchontans in possessing a laterally keeled ulnar trochlea, a distinct
zona conoidea, and a spherical capitulum. These features also suggest an
arboreal lifestyle. The ulnar morphology is consistent with that of the
humerus in reflecting an arboreal/scansorial animal. Detailed quantitative
comparisons indicate that, despite morphological correlates to
euarchontan-like arboreality, the humerus of Deccanolestes is
morphologically intermediate between those of Cretaceous "condylarthran"
mammals and definitive Cenozoic euarchontans. Additionally, humeri
attributed to adapisoriculids are morphologically intermediate between those
of Deccanolestes and definitive euarchontans. If adapisoriculids are
euarchontans, as recently proposed, our results suggest that Deccanolestes
is more basal. The tentative identification of Deccanolestes as a basal stem
euarchontan suggests that (1) Placentalia began to diversify and Euarchonta
originated before the Cretaceous-Tertiary boundary and (2) the Indian
subcontinent, Eurasia, and Africa are more likely places of origin for
Euarchonta than is North America.
Li, Q., Gao, K.-C., Vinther, J., Shawkey, M.D., Clarke, J.A., D'Alba, L.,
Meng, Q., Briggs, D.E.G., Miao, L., and Prum, R.O. 2010. Plumage color
patterns of an extinct dinosaur. Science. doi: 10.1126/science.1186290.
ABSTRACT: As long as dinosaurs have been known, there has been speculation
about their appearance. Fossil feathers can preserve the morphology of
color-imparting melanosomes, which allows color patterns in feathered
dinosaurs to be reconstructed. Here, we map feather color patterns in a Late
Jurassic basal paravian theropod dinosaur. Quantitative comparisons with
melanosome shape and density in extant feathers indicate that the body was
gray and dark and the face had rufous speckles. The crown was rufous, and
the long limb feathers were white with distal black spangles. The evolution
of melanin-based within-feather pigmentation patterns may coincide with that
of elongate pennaceous feathers in the common ancestor of Maniraptora,
before active powered flight. Feathers may thus have played a role in sexual
selection or other communication.
Lü, J., Xu, L., Jiang, X., Jia, S., Li, M., Yuan, C., Zhang, X., and Ji, Q.
2009. A preliminary report on the new dinosaurian fauna from the Cretaceous
of the Ruyang Basin, Henan Province of central China. Journal of the
Paleontological Society of Korea 25(1):43-56.
ABSTRACT: A new dinosaur fauna, the Ruyang Gigantic Sauropod Dinosaurian
Fauna from the early Late Cretaceous of the Ruyang Basin is named. The new
dinosaurian fauna is dominated by large-sized sauropod dinosaurs, companying
with theropod dinosaurs, such as ornithomimid, oviraptorid, spinosaurid and
carcharodontosaurid dinosaurs. Two new taxa are erected, they are a
oviraptorid dinosaur Luoyanggia liudianensis gen. et sp. nov., and a
sauropod Xianshanosaurus shijiagouensis gen et sp. nov. The dinosaur
assemblage from the Ruyang Basin indicates that the dinosaur-bearing
deposits are Cenomanian in age.
Lockley, M.G., and Harris, J.D. 2010. On the trail of early birds: a review
of the fossil footprint record of avian morphological and behavioral
evolution; pp. in Ulrich, P.K. and Willett, J.H. (eds.), Trends in
Ornithology Research. Nova Publishers, Hauppauge. (OPEN ACCESS:
https://www.novapublishers.com/catalog/product_info.php?products_id=14144)
ABSTRACT: Fossil footprints provide important evidence regarding the
morphology, behavior, distribution, and ecology of ancient animals. In
recent years, the ichnological record (pertaining to fossils other than
skeletal or body parts, most familiarly and commonly tracks) of major
tetrapod clades has been studied intensively. The body fossil record amply
demonstrates that the origin of birds lies within the theropod dinosaur
lineage (making birds extant dinosaurs, in an evolutionary sense), but the
ichnological record contributes much valuable information concerning
behavioral shifts during both this evolutionary transition and the early
diversification of birds. Here, for the first time, we review the entire
avian track record, including its specialized ichnotaxonomy, from the
Mesozoic (the "Age of Reptiles," 250-65 million years ago) and Cenozoic (the
"Age of Mammals and Birds," 65 million years ago through the present,
including the Holocene) and consider how the evidence impacts the
understanding of avian evolution and ecology.
Fossil footprints provide important evidence regarding the morphology,
behavior, distribution, and ecology of ancient animals. In recent years, the
ichnological record (pertaining to fossils other than skeletal or body
parts, most familiarly and commonly tracks) of major tetrapod clades has
been studied intensively. The body fossil record amply demonstrates that the
origin of birds lies within the theropod dinosaur lineage (making birds
extant dinosaurs, in an evolutionary sense), but the ichnological record
contributes much valuable information concerning behavioral shifts during
both this evolutionary transition and the early diversification of birds.
Here, for the first time, we review the entire avian track record, including
its specialized ichnotaxonomy, from the Mesozoic (the "Age of Reptiles,"
250-65 million years ago) and Cenozoic (the "Age of Mammals and Birds," 65
million years ago through the present, including the Holocene) and consider
how the evidence impacts the understanding of avian evolution and ecology.
Growing evidence from both the skeletal and track records indicates
that the initial avian taxonomic, morphological, and ecological radiations
took place around the Jurassic-Cretaceous boundary (about 145 million years
ago). Tracks similar to, and in some cases indistinguishable from, those
made by modern shorebirds (Charadriiformes), small ducks (Anseriformes),
small herons (Ciconiidae), and even roadrunners (Cuculiformes) appeared, and
were even regionally abundant only 15-20 million years thereafter. In
contrast, the oldest body fossil records of anseriforms and possibly
charadriiforms occur very close to the end of the Cretaceous (roughly 70
million years ago), and later still for ciconiiforms and cuculiforms. This
strongly implies that the early track makers were members of extinct, early
avian lineages with which later taxa converged in foot morphology. Feeding
traces associated with some of these tracks demonstrate that behaviors
reminiscent of extant herons and spoonbills had also evolved by this time.
However, despite significant skeletal and footprint finds, there is little
correspondence between the records - few footprints match the feet of birds
represented by skeletal remains. In short, the familiar morphologies and
behaviors of many modern birds actually evolved convergently with many of
their extinct, Mesozoic relatives. Footprints thus have the dual benefits of
providing an important, and unexpected, complementary record of early avian
morphological and ecological diversity while highlighting the importance of
morphological and behavioral convergence.
Although the skeletal record suggests an avian taxonomic shift at the
"dinosaur-killing" Cretaceous-Paleogene (K-Pg) boundary extinction event,
the track record provides insufficient evidence to support or refute such a
shift because the dominance of shorebird-like tracks continues uninterrupted
from Mesozoic to Cenozoic. Early Paleogene tracks provide evidence of large,
Diatryma- or Gastornis-like, ground dwelling birds in addition to typical
shorebirds and waterbirds like the Eocene anseriform Presbyornis. Neogene
tracks include those of a few large ratites and a turkey-like species;
Holocene tracks include those of several species of moa. Unlike its Mesozoic
counterpart, the Cenozoic avian body fossil and ichnological records
correspond much more closely.
Tracks of perching birds, raptors, and other groups that do not
habitually frequent wet shorelines - the most suitable environment for track
preservation - are rare. Indeed, the avian track record is dominated by the
footprints of shorebirds, with a minor component attributable to large
flightless and cursorial forms. Nevertheless, the body of literature on
fossil bird tracks is still relatively small (~200 reports), describing
about 6 ichnofamilies, comprising about 38 named ichnogenera and 65
ichnospecies.
Zhao, L.-J., Sato, T., Liu, J., Li, C., and Wu, X.-C. 2010. A new skeleton
of Miodentosaurus brevis (Diapsida: Thalattosauria) with a further study of
the taxon. Vertebrata PalAsiatica 48(1):1-10.
ABSTRACT: A new thalattosaurian skeleton from the Upper Triassic Wayao
Member of the Falang Formation, Guanling area, Guizhou Province, China can
be referred to Miodentosaurus brevis. The postcranial skeleton of the
specimen is well-preserved and so complete that it is worthy to be
described. This new specimen provides a full knowledge of the osteology of
the thalattosaurian, especially the anatomy of the pectoral girdle and both
the fore- and hind-limbs. The presence of a few teeth restricted to the
anterior ends of both the upper and lower jaws and dorsoventrally flattened
ungual phalanges indicate that M. brevis is not a pure carnivore. With new
information, some individual variations are recognized and the digital
formula (2-3-4-5-5) of the pes can be identified as one of the diagnostic
features for the thalattosaurian.
Zhang, S.-K., and Wang, Q. 2010. A new oospecies of ovaloolithids from
Turpan Basin in Xinjiang, China. Vertebrata PalAsiatica 48(1):71-75.
Benton, M.J., Csiki, Z., Grigorescu, D., Redelstorff, R., Sander, P.M.,
Stein, K., and Weishampel, D.B. 2010. Dinosaurs and the island rule: The
dwarfed dinosaurs from Haţeg Island. Palaeogeography, Palaeoclimatology,
Palaeoecology. doi: 10.1016/j.palaeo.2010.01.026.
ABSTRACT: Islands are fascinating natural laboratories of evolution. One
much debated theme among evolutionary ecologists is whether there is an
'island rule', the observation that large animals tend to become smaller and
small animals larger. Franz Nopcsa was the first, in 1914, to suggest that
the latest Cretaceous dinosaurs from Haţeg, Romania were an island fauna,
based on its low diversity and apparently unbalanced composition, and the
basal position ("primitiveness") of many of the included taxa within their
respective clades. In turn, the small size of the taxa compared to their
relatives from other landmasses in conjunction with the proposed island
setting were used to support the presence of the island rule and size
reduction (dwarfing; nanism) among the Haţeg dinosaurs. In Nopcsa's day,
palaeontologists had seen the same phenomenon many times in the Pliocene,
Pleistocene, and Holocene mammals of the Mediterranean islands. Although
often quoted as a key Mesozoic example of the island rule, the supposedly
dwarfed Haţeg dinosaurs have never been investigated thoroughly. Here we
review a wealth of new data, from tectonics and regional geology to limb
proportions and dinosaur bone histology, which support Nopcsa's original
claim of insularity of the Haţeg fauna. Current evolutionary studies confirm
that the island rule applies in many, if not all, modern cases, as well as
to the Mediterranean island mammals. Geological evidence confirms that Haţeg
was probably an island in the Late Cretaceous, and phylogenetic, ecological,
and bone histological evidence shows that at least two of the Haţeg
dinosaurs, the sauropod Magyarosaurus and the ornithopod Telmatosaurus, as
well as possibly the ornithopod Zalmoxes, were dwarfs by progenesis, a form
of paedomorphosis.
Grigorescu, D. 2010. The Latest Cretaceous fauna with dinosaurs and mammals
from the Haţeg Basin - a historical overview Palaeogeography,
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2010.01.030.
ABSTRACT: Research on the uppermost Cretaceous continental deposits with
dinosaur remains from the Haţeg Basin has behind it a history of more than
110 years. The first studies were by Franz Nopcsa (1877-1933) who published
between 1897 and 1929 a series of notes and papers on this fauna, including
five monographs dedicated to the Haţeg dinosaurs. Nopcsa described 10
vertebrate taxa, including dinosaurs, crocodilians and turtles, from the
Haţeg Basin, out of which 6 are still valid. He recognized the primitiveness
and the small size of most of the taxa from the Haţeg palaeofauna,
characters that he related to the isolated island environment within which
this fauna lived for a long time span.
After Nopcsa, systematic research on the Haţeg fauna was interrupted
for many decades, being resumed after 1977 when D. Grigorescu, leading a
small group of students in Geology started to explore the deposits
outcropping along the Sibişel valley, near Sânpetru village, from where
Nopcsa made most of his collection of fossil bones. Since then the fieldwork
continued every summer until now, numerous remains of dinosaurs, crocodiles
and turtles being unearthed. The list of the Maastrichtian fauna from Haţeg
currently includes 56 taxa from all vertebrate classes. More than half of
the recorded taxa were discovered in micropalaeontological samples through
screen-washing. The most spectacular discoveries made after 1977 include a
large variety of small theropods, several sites with dinosaur egg clutches,
one of these also yielding hatchling remains, one of the largest pterosaurs
in the world, representing a new genus and species, Hatzegopteryx thambema,
and several taxa of multituberculate mammals.
Studies of the Haţeg fauna were not restricted to systematic
palaeontology, but also covered all the fields that contribute together to
an accurate reconstruction of the environment within which the Maastrichtian
fauna existed. This overview includes a list of contributors to the actual
knowledge on the Haţeg fauna, during the last 30 years, divided by fields of
scientific interest.
Clarke, A., and Pörtner, H.-O. 2010. Temperature, metabolic power and the
evolution of endothermy. Biological Reviews. doi:
10.1111/j.1469-185X.2010.00122.x.
ABSTRACT: Endothermy has evolved at least twice, in the precursors to modern
mammals and birds. The most widely accepted explanation for the evolution of
endothermy has been selection for enhanced aerobic capacity. We review this
hypothesis in the light of advances in our understanding of ATP generation
by mitochondria and muscle performance. Together with the development of
isotope-based techniques for the measurement of metabolic rate in
free-ranging vertebrates these have confirmed the importance of aerobic
scope in the evolution of endothermy: absolute aerobic scope, ATP generation
by mitochondria and muscle power output are all strongly
temperature-dependent, indicating that there would have been significant
improvement in whole-organism locomotor ability with a warmer body. New data
on mitochondrial ATP generation and proton leak suggest that the thermal
physiology of mitochondria may differ between organisms of contrasting
ecology and thermal flexibility. Together with recent biophysical modelling,
this strengthens the long-held view that endothermy originated in smaller,
active eurythermal ectotherms living in a cool but variable thermal
environment. We propose that rather than being a secondary consequence of
the evolution of an enhanced aerobic scope, a warmer body was the means by
which that enhanced aerobic scope was achieved. This modified hypothesis
requires that the rise in metabolic rate and the insulation necessary to
retain metabolic heat arose early in the lineages leading to birds and
mammals. Large dinosaurs were warm, but were not endotherms, and the
metabolic status of pterosaurs remains unresolved.
Catalano, S.A., Goloboff, P.A., and Giannini, N.P. 2010. Phylogenetic
morphometrics (I): the use of landmark data in a phylogenetic framework.
Cladistics. doi: 10.1111/j.1096-0031.2010.00302.x.
ABSTRACT: A method for the direct use of aligned landmark data (2D or 3D
coordinates of comparable points) in phylogenetic analysis is described. The
approach is based on finding, for each of the landmark points, the ancestral
positions that minimize the distance between the ancestor/descendant points
along the tree. Doing so amounts to maximizing the degree to which similar
positions of the landmarks in different taxa can be accounted for by common
ancestry, i.e. parsimony. This method requires no transformation of the
aligned data or the results: the data themselves are the x, y, z coordinates
of the landmarks, and the output of mapping a character onto a given tree is
the x, y, z coordinates for the hypothetical ancestors. In the special case
of collinear points, the results are identical to those of optimization of
(continuous) additive characters.
Valasek, P., Theis, S., Krejci, E., Grim, M., Maina, F., Shwartz, Y., Otto,
A., Huang, R., and Patel, K. 2010. Somitic origin of the medial border of
the mammalian scapula and its homology to the avian scapula blade. Journal
of Anatomy. doi: 10.1111/j.1469-7580.2009.01200.x.
ABSTRACT: The scapula is the main skeletal element of the pectoral girdle
allowing muscular fixation of the forelimb to the axial skeleton. The
vertebrate limb skeleton has traditionally been considered to develop from
the lateral plate mesoderm, whereas the musculature originates from the
axial somites. However, in birds, the scapular blade has been shown to
develop from the somites. We investigated whether a somitic contribution was
also present in the mammalian scapula. Using genetic lineage-tracing
techniques, we show that the medial border of the mammalian scapula develops
from somitic cells. The medial scapula border serves as the attachment site
of girdle muscles (serratus anterior, rhomboidei and levator scapulae). We
show that the development of these muscles is independent of the mechanism
that controls the formation of all other limb muscles. We suggest that these
muscles be specifically referred to as medial girdle muscles. Our results
establish the avian scapular blade and medial border of the mammalian
scapula as homologous structures as they share the same developmental
origin.
Joyce, W.G., and Lyson, T.R. 2010. A neglected lineage of North American
turtles fills a major gap in the fossil record. Palaeontology. doi:
10.1111/j.1475-4983.2009.00929.x.
ABSTRACT: The fossil record of the two primary subclades of softshell
turtles (Trionychidae) is exceedingly asymmetric, as a result of a ghost
range of total clade Cyclanorbinae that is estimated at 80 Ma. Herein, we
present the first phylogenetic analysis of Trionychidae that includes a
representative of the poorly studied taxon Plastomenidae, which is known
from the Campanian to Eocene of North America. The analysis reveals that
plastomenids are stem cyclanorbines, thus significantly reducing the
apparent ghost range of total group Cyclanorbinae to approximately 30 Ma.
Plastomenids are either an early branching clade of stem Cyclanorbinae, or
they represent a paraphyletic grade that gave rise to modern cyclanorbines.
Although abundant, the fossil record is still too poorly understood to
distinguish between these two primary hypotheses. The previously persistent
extremely long ghost range of total clade Cyclanorbinae appears to have been
the result of a research bias.
Mayr, G., and Smith, T. 2010. Bony-toothed birds (Aves: Pelagornithidae)
from the Middle Eocene of Belgium. Palaeontology. doi:
10.1111/j.1475-4983.2009.00930.x.
ABSTRACT: We describe well-preserved remains of the Pelagornithidae
(bony-toothed birds) from the middle Eocene of Belgium, including a sternum,
pectoral girdle bones and humeri of a single individual. The specimens are
tentatively assigned to Macrodontopteryx oweni Harrison and Walker, 1976,
which has so far only been known from the holotype skull and a referred
proximal ulna. Another species, about two times larger, is represented by an
incomplete humerus and tentatively identified as Dasornis emuinus
(Bowerbank, 1854). The fossils provide critical new data on the osteology of
the pectoral girdle of bony-toothed birds. For the first time, the sternum
of one of the smaller species is preserved, and this bone exhibits a more
plesiomorphic morphology than the recently described sternum of the giant
Miocene taxon. The coracoid resembles that of the Diomedeidae (albatrosses)
in overall morphology, but because bony-toothed birds lack apomorphies of
the Procellariiformes, the similarities are almost certainly owing to
convergence. Bony-toothed birds were often compared with the
'Pelecaniformes' by previous authors, who especially made comparisons with
the Sulidae (gannets and boobies). However, the coracoid distinctly differs
from that of extant 'pelecaniform' birds, and the plesiomorphic presence of
a foramen nervi supracoracoidei as well as the absence of a well-delimited
articulation facet for the furcula supports a position outside the Suloidea,
the clade to which the Sulidae belong.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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