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There Will Be New Papers
I'm baaaaaaa-aaaaack...and I've brought some new references with me!
Kundrát, M., Cruickshank, A.R.I., Manning, T.W., and Nudds, J. 2008. Embryos
of therizinosauroid theropods from the Upper Cretaceous of China: diagnosis
and analysis of ossification patterns. Acta Zoologica 88. doi:
ABSTRACT: Exceptionally complete, in ovo dinosaur embryos from the Upper
Cretaceous of China are analysed. Ossification patterns of these embryos
suggest that they died during the final third of their development. The
therizinosauroid identity of the embryos follows from: (1) an edentulous
premaxilla with a sharp downturned edge; (2) dentary with a lateral shelf;
(3) teeth with fan-shaped crowns, with a few marginal cusps; (4) humerus
with a massive deltopectoral crest extending proximally, with a pointed
proximomedial tuberosity; (5) ilium with an expanded and hooked
preacetabular process; (6) strongly curved hypertrophied manual unguals
tapering to sharp points. These embryos are closest to two Chinese
therizinosauroids, Neimongosaurus yangi Zhang et al. 2001 and Erliansaurus
bellamanus Xu et al. 2002. An elongated narial opening, reduced
basipterygoid process, low cervical neural spines, a transversely narrow
pubic apron, and a pubic foot expanded anteriorly are found in these embryos
and are synapomorphies uniting the Therizinosauroidea and the
Oviraptorosauria. Fusion of cervical and caudal neural arches and centra,
complete ossification of thoracic ribs and ilium, possible co-ossification
of tibia and fibula, fused pubes, complete meta- and acropodial elements,
together with small portions of unossified epiphyses of long bones suggest
an advanced precociality of these embryos.
Martin, J.E., and Benton, M.J. 2008. Crown clades in vertebrate
nomenclature: correcting the definition of Crocodylia. Systematic Biology
57(1):173-181. doi: 10.1080/10635150801910469.
Advocates using Crocodylia for what is now the Crocodyliformes (e.g.,
_Protosuchus_ on up -- all crocodylomorphs except the Sphenosuchia). I
don't agree; I think Jim Clark et al.'s use as a crown-clade only is too
Lockley, M.G., Kim, J.Y., Kim, K.S., Kim, S.H., Matsukawa, M., Rihui, L.,
Li, J., and Yang, S.-Y. 2008. Minisauripus -- the track of a diminutive
dinosaur from the Cretaceous of China and South Korea: implications for
stratigraphic correlation and theropod foot morphodynamics. Cretaceous
Research 29(1):115-130. doi: 10.1016/j.cretres.2007.04.003.
ABSTRACT: The diminutive (2.5?3.0 cm long), Cretaceous dinosaur track
ichnogenus Minisauripus, previously known only from the type ichnospecies,
M. chuanzhuensis, from a single locality in Sichuan Province China, is here
reported from two new localities in South Korea and one in China. Material
from the new Chinese locality is assigned to the new ichnospecies M.
zhenshuonani on the basis of its distinctive morphology. Most of the new
material is well-preserved, revealing narrow asymmetric tracks with claw
traces, long step and phalangeal formula (2-3-4 for digits II, III and IV,
respectively), suggesting a theropod track maker rather than an
ornithischian, as originally inferred for the Chinese type material.
The South Korean samples (eight tracks), from two localities in the
Haman Formation, are considered Early Cretaceous (Aptian-Albian) in age,
whereas the Chinese type material (21 specimens) has been assigned both an
Early and Late Cretaceous age. The former age is probably correct as
suggested by a new Minisauripus locality (5 specimens) from the Early
Cretaceous (Barremian-Albian) of Shandong Province, China.
Other diminutive tracks from the Sichuan fauna include Aquatilavipes
sinensis (2.5 cm long, a possible junior synonym of Koreanoris hamanensis),
Grallator emeiensis (2 cm long) and Velociraptorichnus sichuanensis (10?11
cm), which occur, in various combinations, with Minisauripus at both the new
Korean and Chinese localities.
In Minisauripus, digit III is very short in comparison with other
theropods and provides a striking contrast to G. emeinsis. This difference
has significant implications for standard assumptions about theropod track
allometry. Based on the classic Early Jurassic forms Grallator and
Eubrontes, it has long been inferred that relative digit III length shrank
with increasing size (up to foot lengths of 30?40 cm). The reiteration of
reduction in relative length of digit III in specimens in the size range of
2?3 cm indicates that the allometric or morphodynamic ?program? that
influenced development in large theropod clades reiterated fractally in
theropod clades a full order of magnitude smaller. This shows that a given
allometry can be size-dependent in one clade and size-independent in
another. Thus, the developmental program appears ?contracted? or
morphologically miniaturized by heterochrony to manifest paedomorphically in
some clades and peramorphically in others. This strongly suggests that
?formal? developmental ?programs operated? along similar morphodynamic lines
in quite different clades.
Ponton, F., Montes, L., Castanet, J., and Cubo, J. 2007. Bone histological
correlates of high-frequency flapping flight and body mass in the furculae
of birds: a phylogenetic approach. Biological Journal of the Linnean Society
91(4):729-738. doi: 10.1111/j.1095-8312.2007.00836.x.
ABSTRACT: A parsimony optimization of the presence of high-frequency
flapping flight onto a phylogeny of 29 species of birds shows that this is a
derived character state that has been acquired at least four independent
times: by the last common ancestor of Alcidae, that of Podicipedidae, that
of Anatidae, and that of Rallidae. Cineradiographic analysis has shown that
the furculae of birds underwent extraordinary deformations during the
wingbeat cycle. Cyclical deformations are known to produce microfractures in
the bone tissue, which may be a stimulus for Haversian remodelling, a
mechanism of resorption and reconstruction of bone tissue that may repair
bone microdamage. In the present study, we performed a comparative analysis
in a phylogenetic context to test the effect of the frequency of cyclical
deformations and body mass on the rate of Haversian remodelling in the
furculae of birds. A variation partitioning analysis showed that the type of
flight (high-frequency flapping flight vs. other kinds of flight of lower
wing beat frequency) and body mass explained a significant portion of
Haversian bone density (the outcome of Haversian remodelling) and that the
phylogeny also explained a significant part of this variation. This
phylogenetic signal on Haversian bone density variation may be the outcome
of phylogenetic signal on the proximate causes producing Haversian
Sano, S.-I., Kubota, K., and Yabe, A. 2008. ?The Cretaceous Tetori biota in
Japan and its evolutionary significance for terrestrial ecosystems in Asia?
[Cretaceous Research 27 (2006) 199?225]?Discussion. Cretaceous Research
27(1):168-173. doi: 10.1016/j.cretres.2006.12.008.
ABSTRACT: Matsukawa et al. present a new interpretation of the age and
geological correlation within the Tetori Group. Comparison of their data
with our own studies and literatures, we comment on some problems remain
unsolved in their paper, such as (1) stratigraphy of the Takinamigawa area,
where various fossils including dinosaurs were recovered; (2) recognition of
the Akaiwa and Tamodani floras, constituents of the Tetori-type flora; (3)
geological correlation of the Tetori Group between the Mt. Hakusan and
Kuzuryugawa regions. Further combination of lithostratigraphy and other
correlation methods is required to improve the understanding of the
stratigraphy of the Tetori Group.
Matsukawa, M., Ito, M., Nishida, N., Marín, Koarai, K., and Lockley, M.
2008. Reply to the Discussion of Sano et al. Cretaceous Research
27(1):174-181. doi: 10.1016/j.cretres.2006.11.007.
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
"There's a saying that goes 'people who live in glass houses shouldn't throw
stones'... OK. How about...NOBODY should throw stones. That's crappy
behavior! My policy is 'no stone-throwing regardless of housing situation.'
There's an exception, though. If you're TRAPPED in a glass house...and you
have a stone, then throw it! What are you, an idiot? It's really 'ONLY
people in glass houses should throw stones'... provided they're trapped, in
a house... with a stone. It's a little longer, but you know..."
--- Demetri Martin