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The New Papers of Eli



Brusatte, S.L., Chure, D.J., Benson, R.B.J., and Xu, X. 2010. The osteology
of Shaochilong maortuensis, a carcharodontosaurid (Dinosauria: Theropoda)
from the Late Cretaceous of Asia. Zootaxa 2334:1-46.

ABSTRACT: Large-bodied theropod dinosaurs from the Early-mid Cretaceous of
the northern continents (Laurasia) are poorly known. One of the most
complete and intriguing theropods from this interval is Shaochilong
maortuensis Hu, 1964 from the Turonian (< 92 Ma) Ulansuhai Formation of
Inner Mongolia, China. The phylogenetic placement of Shaochilong has long
been a subject of debate, as it has been referred to several disparate
theropod groups (e.g., Megalosauridae, Allosauridae, Tyrannosauroidea,
Maniraptora). In a recent taxonomic reassessment, Shaochilong was identified
as the first Asian member of Carcharodontosauridae, a clade of allosauroid
theropods that was once thought to be restricted to Gondwana and includes
some of the largest terrestrial predators to ever live. However, the
characters supporting such a placement were only briefly discussed, and a
full anatomical description of Shaochilong has yet to be presented. We
provide a detailed osteological description of the lectotype and
paralectotype series, show that Shaochilong is a smallbodied and
short-snouted carcharodontosaurid, and highlight numerous cranial features
shared with other carcharodontosaurids. We argue that the vicariant
hypothesis of allosauroid biogeography, in which lineages split in concert
with the fragmentation of Pangaea, is poorly supported. Finally, large-scale
patterns of theropod evolution and faunal replacement are discussed, and it
is argued that allosauroids persisted as large-bodied predators later in the
Cretaceous than previously thought.





Wolff, E.D.S. 2010. The limitations of homology in vertebrate
paleopathology. Historical Biology 21(3-4):235-238. doi:
10.1080/08912960903471196.  





Beatty, B.L., and Rothschild, B.M. 2010. Paleopathologies are features of an
organism and its interaction with the environment and should not be treated
like organisms unto themselves. Historical Biology 21(3-4):229-233. doi:
10.1080/08912960903469711.

ABSTRACT: Though the history of disease has an evolutionary history in
itself, this history of pathologies, which are physical manifestations of
immune responses to disease processes, has a history that is intimately
linked to the history of the host organisms themselves. But many of these
physical manifestations of an organism's response to disease are related to
aspects of the immune system that are rooted so deeply in the phylogeny of
vertebrates, or at least amniotes, that one must exercise caution when
interpreting a pathology as novel. Here, we argue that the interpretation of
paleopathologies must be founded on the basis of disease manifestations
which relate to phylogeny, but recognise that much of this relationship is
so deeply rooted that novel paleopathologies would be rare. The former
presents an interesting speculation, but does not allow for placement of
findings within an ecological and chronological context. Likewise, the
assignment of specimens as paleopathological holotypes defeats this purpose
in attempting to narrowly define the physical manifestation of the immune
response to disease, doing nothing more than a photographic library of
paleopathologies could do, but not conveying the true nature of
paleopathologies and could lead to artificial classification schemes that
would cause more confusion than clarity. 





Isles, T.E. 2010. The socio-sexual behaviour of extant archosaurs:
implications for understanding dinosaur behaviour. Historical Biology
21(3-4): 139-214. doi: 10.1080/08912960903450505

ABSTRACT:  Dinosaur behaviour has little legacy in the fossil record and the
rarity of fossil soft tissues makes it difficult to evaluate. Indirect
evidence from bonebeds, trackways, nesting traces and in-group comparisons
with extant Archosauria suggests that the only substantive arguments to be
made for dinosaur sociality concern cranial ornamentation and herding
behaviour. There is currently no reliable method to determine gender from
skeletal remains. Dinosaur reproductive anatomy was a unique combination of
crocodilian and avian characters and extant models indicate that dinosaurs
copulated using a reptilian 'leg over back' posture. Reliable evidence for
post-hatching care in dinosaurs is lacking and extant archosaurs yield
little insight. A hypothesis is proposed that for the majority of dinosaurs
there was no post-hatching care provided which would have allowed adults
energy acquisition that would otherwise have been required for defence and
provisioning to be redirected towards growth and increased fecundity, both
traits for which there is fossil evidence. Arguments suggesting that the
more advanced aspects of extant avian care boasting an explicit
coelurosaurian theropod origin are rejected as these behaviours appear
unique to the Neornithes. Three ancestral care hypotheses are tested and
none conform in a satisfactory manner with body fossil and ichnological
evidence.






Hedman, M.M. 2010. Constraints on clade ages from fossil outgroups.
Paleobiology 36(1):16-31. doi: 10.1666/0094-8373-36.1.16.

ABSTRACT: This paper presents a method for constraining the age of a clade
with the ages of the earliest fossil specimens in that clade's outgroups.
Given a sufficiently deep, robust, well-resolved, and stratigraphically
consistent cladogram, this method can yield useful age constraints even in
the absence of specific information about the fossil preservation and
recovery rates of individual taxa. The algorithm is applied to simulated
data sets to demonstrate that this method can yield robust constraints of
clade ages if there are sufficient fossil outgroups available and if there
is a finite chance that additional outgroups may be discovered in the
future. Finally, the technique is applied to actual fossil data to explore
the origin of modern placental mammals. Using data from recently published
cladograms, this method indicates that if all Mesozoic eutherians are
regarded as outgroups of Placentalia, then the last common ancestor of
modern placental mammals and their Cenozoic allies lived between 65 and
88?98 million years ago, depending on the assumed cladogram and the number
of outgroups included in the analysis.






Abdala, F., and Ribeiro, A.M. 2010. Distribution and diversity patterns of
Triassic cynodonts (Therapsida, Cynodontia) in Gondwana. Palaeogeography,
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2010.01.011.

ABSTRACT: Cynodonts are an important component of Triassic tetrapod faunas
and are frequently one of the dominant groups. A summary of their record
during the Triassic of Gondwana is presented. Cynodonts are represented by
63 species/57 genera in Gondwana with diversification peaks occurring during
the Late Anisian (particularly in Africa) and the Carnian of South America
and India. Data on the number of faunas of each age and the duration (in
millions of years) estimated for these faunas were integrated with cynodont
generic diversity values. One of the most important turnovers in cynodonts
occurred at the Late Olenekian-Anisian, involving changes in two directions:
a) the record of complex bucco-lingually expanded (gomphodont) postcanines,
with traversodontid cynodonts already representing an important group at the
end of the Anisian; b) the record, particularly during the Anisian, of
significantly large-sized cynodonts (e.g. Cynognathus and Diademodon with
basal skull length between 30 to 40 cm). Considering that the global maximum
peak of cynodont diversity is during the Norian-Rhaetian, the diversity of
Gondwanan cynodonts for that time, eight taxa, is remarkably low.





Mayr, G., and Micklich, N. 2010. New specimens of the avian taxa
Eurotrochilus (Trochilidae) and Palaeotodus (Todidae) from the early
Oligocene of Germany. Paläontologische Zeitschrift. doi:
10.1007/s12542-009-0047-z.

ABSTRACT: We describe new specimens of stem group representatives of
Trochilidae (hummingbirds) and Todidae (todies) from the Rupelian of
Frauenweiler in southern Germany. The hummingbird fossil constitutes the
fourth record of Eurotrochilus inexpectatus. It consists only of wing and
pectoral girdle elements, but shows the previously unknown crista
deltopectoralis of the humerus, whose shape differs from modern
hummingbirds. The carpometacarpus bears a well-developed processus
intermetacarpalis, which is a further synapomorphy of Eurotrochilus and
crown group Trochilidae. The disarticulated partial skeleton of the tody
allows a definitive taxonomic assignment of the Frauenweiler species to
Palaeotodus itardiensis Mourer-Chauviré, and likewise exhibits so far
unknown osteological details, including the morphologies of the quadrate and
scapula. We further comment on the exceptional taphonomy and preservation of
avian fossils from the Frauenweiler clay pit, where terrestrial birds are
represented only by small to very small species, whose skeletons are always
strongly disarticulated. 





Bravi, S., Barone Lumaga, M.R., and Mickle, J.E. 2010. Sagaria cilentana
gen. et sp. nov. - a new angiosperm fructification from the Middle Albian of
southern Italy. Cretaceous Research. doi: 10.1016/j.cretres.2009.12.001.

ABSTRACT: A single specimen of a new fossil angiosperm, Sagaria cilentana
gen. et sp. nov., has been recovered from limestones of the ?plattenkalk? of
the Middle Albian at Monti Alburni, near Petina, Campania, Italy. Associated
fossils include Pagiophyllum sp., Podozamites sp. and Zamites sp. The
angiosperm has a main axis approximately 8 cm long with three attached
leaves and a distal cyme bearing three fructifications. The fructifications
display divided distal tips indicating three - four lobes. Four cm from the
base, underneath the main axis, there is a lobed structure, presumably a
leaf. An unattached leaf near the specimen is in a position that suggests
that it comes from the same plant. The leaf has an elongate petiole, obtuse
base and on the right side of the lamina are three lobes. Affinities are
uncertain but show similarities in overall morphology to basal eudicots,
especially Ranunculaceae.






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