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He's Just Not That Into New Papers

Watabe, M., Tsogtbaatar, K., and Barsbold, R. 2008. First discovery of a
theropod (Dinosauria) from the Upper Jurassic in Mongolia and its
stratigraphy. Paleontological Research 12(1):27-36. doi:

ABSTRACT: A theropod dinosaur is described for the first time from the Upper
Jurassic of Mongolia. It is represented by a partial skull from the upper
Jurassic Dariv Suite in Dariv, Ikhes Nuur Basin, Gobi-Altai Aimag, western
Mongolia, situated relatively close to the Xinjiang Uygur Autonomous
Province in the western part of China. From the same beds of the locality,
sauropod bones were also abundantly found. Those fossil discoveries suggest
that both carnivorous and herbivorous dinosaurs existed in the Jurassic of
Mongolia, as in China.

Foster, J.R. 2009. Preliminary body mass estimates for mammalian genera of
the Morrison Formation (Upper Jurassic, North America). PaleoBios

ABSTRACT: Dentitions of Late Jurassic mammals from the Morrison Formation of
the Rocky Mountain region of western North America do not closely fit dental
patterns of modern small mammals; thus, traditional techniques for
estimating body masses of extinct forms based on single molar dimensions may
not be appropriate for these Mesozoic taxa. A regression of dentary length
to body mass of extant small marsupial mammals is presented here and used
for body mass estimates of mammals from the Morrison Formation. Dentary
length was more closely correlated to body mass than was molar row length in
modern marsupial mammals. The body mass distribution for mammalian genera of
the Morrison Formation demonstrates a right-skewed curve and shows a range
from 6g to 141 g, a mean weight for individual genera of 48.5 g, and a peak
diversity at 5-25 g. The largest and smallest mammals from the Morrison
Formation are Docodon at 141 g and Fruitafossor at 6 g.

Shapiro, R.S., Fricke, H.C., and Fox, K. 2009. Dinosaur-bearing oncoids from
ephemeral lakes of the Lower Cretaceous Cedar Mountain Formation, Utah.
Palaios 2(4):51-58. doi: 10.2110/palo.2008.p08-013r.

ABSTRACT: Here we document the occurrence of locally common oncoids in the
Cedar Mountain Formation of Utah in the Woodside Anticline area of the San
Rafael Swell and use them to understand changes in the Early Cretaceous
landscape and their effects on the dinosaur fauna. Detailed facies analysis
is required to understand the context of these changes within the broader
patterns of Mesozoic tectonics and the fossil record. Oncolite crops out in
the Cedar Mountain Formation, directly overlying the Buckhorn Conglomerate.
Oncolite is not widely distributed outside of the Woodside Anticline area.
The oncoids are found in a bimodal population with the majority in the
2-5-cm-diameter range and a smaller population >25 cm in diameter. Nuclei
are mostly rounded chert clasts and also include litharenite, polymict
conglomerate, limestone, and both abraded and nonabraded dinosaur bone and
wood fragments. Cortices are 3-5 mm thick with distinct, penecint (laminae
that completely enclose a body; Hofmann, 1969), low-relief laminae. Some
laminae are crenulated and comprise ministromatolites. The petrography of
the oncoids suggests formation along lake margins where large fragments of
reworked sedimentary clasts and dinosaur bones came to rest and were coated
by bacterial mats. Caliche cements and coats some of the oncolite; these
define a lake shoreline affected by fluctuating lake level. The isotope
geochemistry indicates a combination of primary and diagenetic signals
consistent with oncoid formation in open, ephemeral freshwater lakes.

Wedel, M.J. 2009. Evidence for bird-like air sacs in saurischian dinosaurs.
Journal of Experimental Zoology 311A. doi: 10.1002/jez.513.

ABSTRACT: Among extant tetrapods, pneumatic postcranial bones are only
present in birds, and they are osteological correlates of the diverticular
lungs and pulmonary air sacs. The presence of postcranial pneumaticity in
sauropod and theropod dinosaurs suggests that some form of air sac system
was also present in the dinosaurian ancestors of birds. In particular,
anatomical and evolutionary patterns of pneumatization in nonavian
saurischian dinosaurs are diagnostic for specific air sacs, including the
cervical, clavicular, and abdominal air sacs. Pneumatic hiatuses are gaps in
the pneumatization of the vertebral column and indicate pneumatization from
multiple sources. A pneumatic hiatus in Haplocanthosaurus provides
additional support for the presence of abdominal air sacs in sauropods. The
origins of postcranial pneumaticity in archosaurs are enigmatic because the
earliest putative traces of pneumaticity are difficult to distinguish from
skeletal imprints of other soft tissues. Nevertheless, several lines of
evidence suggest that air sac-driven lung ventilation was primitive for

Krug, A.Z., Jablonski, D., and Valentine, J.W. 2009. Signature of the
end-Cretaceous mass extinction in the modern biota. Science 323:767-771.
doi: 10.1126/science.1164905.

ABSTRACT: The long-term effects of mass extinctions on spatial and
evolutionary dynamics have been poorly studied. Here we show that the
evolutionary consequences of the end-Cretaceous [Cretaceous/Paleogene
(K/Pg)] mass extinction persist in present-day biogeography. The geologic
ages of genera of living marine bivalves show a significant break from a
smooth exponential distribution, corresponding to the K/Pg boundary. The
break reflects a permanent increase in origination rates, intermediate
between the Mesozoic rate and the post-extinction recovery pulse. This
global rate shift is most clearly seen today in tropical bioprovinces and
weakens toward the poles. Coupled with the modern geographic distributions
of taxa originating before and after the K/Pg boundary, this spatial pattern
indicates that tropical origination rates after the K/Pg event have left a
permanent mark on the taxonomic and biogeographic structure of the modern
biota, despite the complex Cenozoic history of marine environments.

Benton, M.J. 2009. The Red Queen and the Court Jester: species diversity and
the role of biotic and abiotic factors through time. Science 323:728-732.
doi: 10.1126/science.1157719.

ABSTRACT: Evolution may be dominated by biotic factors, as in the Red Queen
model, or abiotic factors, as in the Court Jester model, or a mixture of
both. The two models appear to operate predominantly over different
geographic and temporal scales: Competition, predation, and other biotic
factors shape ecosystems locally and over short time spans, but extrinsic
factors such as climate and oceanographic and tectonic events shape
larger-scale patterns regionally and globally, and through thousands and
millions of years. Paleobiological studies suggest that species diversity is
driven largely by abiotic factors such as climate, landscape, or food
supply, and comparative phylogenetic approaches offer new insights into
clade dynamics.

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

"Life is the art of drawing
sufficient conclusions from
insufficient premises."
               -- Samuel Butler