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How to Train Your New Papers



Paul, G.S., and Carpenter, K. 2010. Allosaurus Marsh, 1877 (Dinosauria,
Theropoda): proposed conservation of usage by designation of a neotype for
its type species Allosaurus fragilis Marsh, 1877. Bulletin of Zoological
Nomenclature 67(1):53-56.




Smith, S.A., Beaulieu, J.M., and Donoghue, M.J. 2010. An uncorrelated
relaxed-clock analysis suggests an earlier origin for flowering plants.
Proceedings of the National Academy of Sciences 107(13):5897-5902. doi:
10.1073/pnas.1001225107.

ABSTRACT: We present molecular dating analyses for land plants that
incorporate 33 fossil calibrations, permit rates of molecular evolution to
be uncorrelated across the tree, and take into account uncertainties in
phylogenetic relationships and the fossil record. We attached a prior
probability to each fossil-based minimum age, and explored the effects of
relying on the first appearance of tricolpate pollen grains as a lower bound
for the age of eudicots. Many of our divergence-time estimates for major
clades coincide well with both the known fossil record and with previous
estimates. However, our estimates for the origin of crown-clade angiosperms,
which center on the Late Triassic, are considerably older than the
unequivocal fossil record of flowering plants or than the molecular dates
presented in recent studies. Nevertheless, we argue that our older estimates
should be taken into account in studying the causes and consequences of the
angiosperm radiation in relation to other major events, including the
diversification of holometabolous insects. Although the methods used here do
help to correct for lineage-specific heterogeneity in rates of molecular
evolution (associated, for example, with evolutionary shifts in life
history), we remain concerned that some such effects (e.g., the early
radiation of herbaceous clades within angiosperms) may still be biasing our
inferences.




Sulej, T. 2010. The skull of an early Late Triassic aetosaur and the
evolution of the stagonolepidid archosaurian reptiles. Zoological Journal of
the Linnean Society 158(4):860-881. doi: 10.1111/j.1096-3642.2009.00566.x.

ABSTRACT: Disarticulated bones of several individuals recovered from the
Late Triassic fluvial and lacustrine deposits at Krasiejów, Poland, are here
described, allowing the restoration of the skull structure of a new
aetosaurian archosaur: Stagonolepis olenkae sp. nov. The Krasiejów deposits
probably correspond in age to the Lehrberg Beds (late Carnian) of
Baden-Württemberg, Germany. The stratigraphical position of the new taxon
combined with other available evidence is used to propose a model of
aetosaurian evolution. The proposed phylogenetic position of Aetosaurus
ferratus (Norian, Germany) as the basal aetosaurid is refuted and this
species is instead proposed to be the most derived member of the
Stagonolepis?Aetosaurus  evolutionary lineage. Gradual change in several
morphological characters can be observed from Stagonolepis robertsoni,
through the new species from Krasiejów, to the stratigraphically youngest
Aetosaurus ferratus. These changes include a decrease in the number of teeth
and a decrease in the convexity of the ventral profile of the maxilla. The
anterior elongation of the maxilla is associated with the expansion of the
anterior tip of the maxilla towards the naris. In S. robertsoni and S.
olenkae, the maxilla extends to middle of the naris, whereas in Aetosaurus,
it reaches the anterior half of the naris.





Young, M.T., Brusatte, S.L., Ruta, M., and Brandalise de Andrade, M. 2010.
The evolution of Metriorhynchoidea (Mesoeucrocodylia, Thalattosuchia): an
integrated approach using geometric morphometrics, analysis of disparity,
and biomechanics. Zoological Journal of the Linnean Society 158(4):801-859.
doi: 10.1111/j.1096-3642.2009.00571.x.

ABSTRACT: Metriorhynchoid crocodylians represent the pinnacle of marine
specialization within Archosauria. Not only were they a major component of
the Middle Jurassic?Early Cretaceous marine ecosystems, but they provide
further examples that extinct crocodilians did not all resemble their modern
extant relatives. Here, we use a varied toolkit of techniques, including
phylogenetic reconstruction, geometric morphometrics, diversity counts,
discrete character disparity analysis, and biomechanical finite-element
analysis (FEA), to examine the macroevolutionary history of this clade. All
analyses demonstrate that this clade became more divergent, in terms of
biodiversity, form, and function, up until the Jurassic?Cretaceous boundary,
after which there is no evidence for recovery or further radiations. A clear
evolutionary trend towards hypercarnivory in Dakosaurus is supported by
phylogenetic character optimization, morphometrics, and FEA, which also
support specialized piscivory within Rhacheosaurus  and Cricosaurus. Within
Metriorhynchoidea, there is a consistent trend towards increasing marine
specialization, with the hypermarine Cricosaurus exhibiting numerous
convergences with other Mesozoic marine reptiles (e.g. loss of the
deltopectoral crest and retracted external nares). In addition,
biomechanics, morphometrics, and character-disparity analyses consistently
distinguish the two newly erected metriorhynchid subfamilies. This study
illustrates that together with phylogeny, quantitative assessment of
diversity, form, and function help elucidate the macroevolutionary pattern
of fossil clades.





Habib, M.B. 2010. The structural mechanics and evolution of aquaflying
birds. Biological Journal of the Linnean Society 99(4):687-698. doi:
10.1111/j.1095-8312.2010.01372.x.

ABSTRACT: Mass-specific bone strength was examined in the forelimb and
hindlimb of 64 species of birds to determine if aquaflying birds (which
utilize the wings for propulsion underwater) differ in their skeletal
strength compared with other avian taxa. Long bone strengths were estimated
from cross-sectional measurements. Compared with the expectation from
geometric similarity, humeral section modulus in volant birds scales nearly
isometrically, while femoral strength scales with significant positive
allometry. Penguin mass-specific humeral strength is greatly elevated, but
the average humeral strength in species that are propelled by the wings in
both air and water do not differ from the values calculated in non-diving
taxa. However, amphibious flyers have gracile femora. Comparative analyses
using independent contrasts were utilized to examine the impact of
phylogenetic signal. The residual measured for the penguin?procellariiform
humeral strength contrast was larger in magnitude (residual of 2.14) than at
any other node in the phylogeny. The data strongly indicate that the
transition from an amphibious flight condition to a fully aquatic condition
involves greater changes in mechanical factors than the transition from
purely aerial locomotion to amphibious wing use. There remains the
possibility that a historical effect, such as ancestral body size, has
impacted the mechanical scaling of penguins.







~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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