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Fantastic Mr. New Papers



Sereno, P.C., and Brusatte, S.L. 2009. Comparative assessment of
tyrannosaurid interrelationships. Journal of Systematic Palaeontology. doi:
10.1017/S1477201909990034.

ABSTRACT: We employ a new comparative method to four cladistic analyses of
tyrannosaurid dinosaurs to identify root causes for differences between
phylogenetic results. The comparative method is a three-step procedure that
(1) adjusts competing hypotheses so they share equivalent taxonomic scope,
(2) isolates the character data relevant to the common problem, and (3)
divides relevant character data into shared and novel partitions. It is then
possible to quantify the degree of similarity between character data using
three indices (ancestor similarity index, character similarity index and
character state similarity index).
     The most parsimonious cladograms generated by the four analyses of
tyrannosaurids appear fairly congruent, with two subclades present in all
four analyses (Albertosaurus and Gorgosaurus versus Daspletosaurus,
Tarbosaurus and Tyrannosaurus). A comparative examination of the underlying
character data, however, highlights striking differences in character
selection and significant differences in character state scores. Character
selection and differences in scoring are root causes for phylogenetic
incongruence. Comparative analysis reveals the existence of many data-level
differences that remain largely obscured when comparison is limited to the
most parsimonious cladograms.






Costa, F.R., and Kellner, A.W.A. 2009. On two pterosaur humeri from the
Tendaguru beds (Upper Jurassic, Tanzania). Anais da Academia Brasileira de
Ciências 81(4):813-818. doi: 10.1590/S0001-37652009000400017.

ABSTRACT: Jurassic African pterosaur remains are exceptionally rare and only
known from the Tendaguru deposits, Upper Jurassic, Tanzania. Here we
describe two right humeri of Tendaguru pterosaurs from the Humboldt
University of Berlin: specimens MB.R. 2828 (cast MN 6661-V) and MB.R. 2833
(cast MN 6666-V). MB.R. 2828 consists of a three-dimensionally preserved
proximal portion. The combination of the morphological features of the
deltopectoral crest not observed in other pterosaurs suggests that this
specimen belongs to a new dsungaripteroid taxon. MB.R. 2833 is nearly
complete, and because of a long and round proximally placed deltopectoral
crest it could be referred to the Archaeopterodactyloidea. It is the
smallest pterosaur from Africa and one of the smallest flying reptiles ever
recorded. These specimens confirm the importance of the Tendaguru deposits
for the Jurassic pterosaur record. This potential, however, has to be fully
explored with more field work.

(available free at
http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0001-37652009000400
017&lng=en&nrm=iso)





Wang, X., Kellner, A.W.A., Jiang, S., and Meng, X. 2009. An unusual
long-tailed pterosaur with elongated neck from western Liaoning of China.
Anais da Academia Brasileira de Ciências 81(4):793-812. doi:
10.1590/S0001-37652009000400016.

ABSTRACT: A new long-tailed pterosaur, Wukongopterus lii gen. et sp. nov, is
described based on an almost complete skeleton (IVPP V15113) representing an
individual with an estimated wing span of 730 mm. The specimen was
discovered in strata that possibly represent the Daohugou Bed (or Daohugou
Formation) at Linglongta, Jianchang, Liaoning Province, China. Wukongopterus
lii is a non-pterodactyloid pterosaur diagnosed by the first two pairs of
premaxillary teeth protruding beyond the dentary, elongated cervical
vertebrae (convergent with Pterodactyloidea), and a strongly curved second
pedal phalanx of the fifth toe. The specimen further has a broken tibia that
indicates an injury occurred while the individual was still alive.
Taphonomic aspects provide indirect evidence of an uropatagium, supporting
the general hypothesis that at least all non-pterodactyloid pterosaurs show
a membrane between the hind limbs. A phylogenetic analysis including most
non-pterodactyloid pterosaurs shows that Wukongopterus lii gen. et sp. nov.
lies outside the Novialoidea, being cladistically more primitive than the
Rhamphorhynchidae and Campylognathoides. This analysis differs from previous
studies and indicates that more work is needed before a stable picture of
non-pterodactyloid pterosaur relationships is achieved.

(available free at
http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0001-37652009000400
016&lng=en&nrm=iso)





Liang, X., Wen, S., Yang, D., Zhou, S., and Wu, S. 2009. Dinosaur eggs and
dinosaur egg-bearing deposits (Upper Cretaceous) of Henan Province, China:
occurrences, palaeoenvironments, taphonomy and preservation. Progress in
Natural Science 19(11):1587-1601. doi: 10.1016/j.pnsc.2009.06.012.

ABSTRACT: The Upper Cretaceous dinosaur egg-bearing deposits in Henan
Province, central China are divided into three formations in ascending
order: Gaogou, Majiacun and Sigou. The Gaogou Formation belongs to alluvial
fan deposits containing the fossil dinosaur egg assemblage of
Faveoloolithus, Dendroolithus, Dictyoolithus, Paraspheroolithus and
Longiteresoolithus. The Majiacun Formation is interpreted as braided stream
to meandering stream deposits with assemblage of Ovaloolithus,
Paraspheroolithus, Placoolithus, Dendroolithus, Prismatoolithus, rare
Youngoolithus and Nanhiungoolithus. The Sigou Formation is shallow
lacustrine/palustrine to low-sinuosity river sedimentary rocks with
assemblage of Macroolithus, Elongatoolithus, Ovaloolithus and
Paraspheroolithus.
     To date, 37 oospecies, 13 oogenera and 8 oofamilies of dinosaur eggs
have been distinguished. Autochthonous dinosaur eggs are preserved in the
floodplain deposits, whereas allochthonous and parautochthonous dinosaur
eggs are preserved in the alluvial fans. This suggests that river
floodplains are the best environments for the preservation of numerous
autochthonous dinosaur eggs. The preservation of most dinosaur eggs in brown
to red calcic palaeosoils, muddy siltstones or mudstones suggests that the
paleoclimate of the nesting area was semiarid. The presence of gray and
green mudstone and coal layers, however, indicates that there existed an
ephemeral subhumid climate during the middle and Late Cretaceous. It is
suggested that such a climate was favorable for the development of
meandering streams in a vegetated environment.





Xu, X., and Guo, Y. 2009. The origin and early evolution of feathers:
insights from recent paleontological and neontological data. Vertebrata
PalAsiatica 47(4):311-329.

ABSTRACT: Recent paleontological and neontological studies on feathers and
feather-like integumentary structures have improved greatly our
understanding of the origin and early evolution of feathers. New
observations on some non-avian dinosaur specimens preserving integumentary
structures, in combination with recent paleontological and neontological
data, provide additional insights into this important evolutionary issue.
Five major morphogenesis events are inferred to have occurred sequentially
early in feather evolution before the origin of the Aves, and they are: 1)
appearance of filamentous and tubular morphology, 2) formation of follicle
and barb ridges, 3) appearance of rachis, 4) appearance of planar form, and
5) formation of pennaceous barbules. These events produce several
morphotypes of feathers that are common among non-avian archosaurs but are
probably lost later in avian evolution, and they also produced several
morphotypes of feathers that are nearly identical or identical to those of
modern birds. While feathers of non-avian dinosaurs exhibit many unique
features of modern feathers, some of them also possess striking features
unknown in modern feathers. Several models of evolutionary origin of
feathers based on developmental data suggest that the origin of feathers is
a completely innovative event and the first feathers have nothing to do with
reptilian scales. We believe, however, that the defining features of modern
feathers might have evolved in an incremental manner rather than in a sudden
way. Consequently, an evolutionary model characteristic of both
transformation and innovation is more acceptable for feather evolution. The
function of the first feather is inferred to be neither related to flight
nor to insulation. Display or heat dissipation, among others, remains viable
hypotheses for initial function of feathers. An integrative study is
promising to provide much new insights into the origin of feathers.

(available free at
http://www.ivpp.cas.cn/cbw/gjzdwxb/xbwzxz/200911/P020091104362654347399.pdf)



Zhou, Z.-H., Zhang, F.-C., and Li, Z.-H. 2009. A new basal ornithurine bird
(Jianchangornis microdonta gen. et sp. nov.) from the Lower Cretaceous of
China. Vertebrata PalAsiatica 47(4):299-310.

ABSTRACT: A new genus and species of a basal ornithurine bird is reported
from the Lower Cretaceous skeleton of a sub-adult individual. It is
distinguishable from other known ornithurines by possessing a combination of
features including at least 16 small and conical teeth on the dentary,
scapula strongly curved, metacarpal I robust and wider than other
metacarpals, first manual digit long and extending beyond distal metacarpal
II, and length ratio of humerus+ulna+metacarpal II to
femur+tibiotarsus+tarsometatarsus is approximately 1.1. Phylogenetic
analysis indicates that the the new taxon is a basal ornithurine.
Jianchangornis represents the second Early Cretaceous bird with the
preservation of a predentary bone, which may further confirm that a
predentary could be a feature common to Mesozoic ornithurines. The advanced
features of the pectoral girdle, sternum and wings of the new bird indicate
its powerful flight capability, and the hindlimb bone and toe proportions as
well as the ungual morphology suggest a terrestrial locomotion similar to
those of Yanornis and Yixianornis. The associated fish fragments may
indicate a piscivorous diet consistent with the dentation of the new bird.
The discovery of a new basal ornithurine further shows that the
diversification of the Ornithurae is probably no less than the
enantiornithes and the near lakeshore adaptation had definitely played a key
role in the early ornithurine radiation.

(available free at
http://www.ivpp.cas.cn/cbw/gjzdwxb/xbwzxz/200911/t20091104_2647437.html)



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/


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