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New Papers Are All Right

Godefroit, P., and Motchurova-Dekova, N. 2010. Latest Cretaceous hadrosauroid 
(Dinosauria: Ornithopoda) remains from Bulgaria. Comptes Rendus Palevol. doi: 

ABSTRACT: Disarticulated dinosaur bones have been discovered in a fossiliferous 
lens in the Labirinta Cave, southwest of the town of Cherven Bryag, in NW 
Bulgaria. This cave is formed within marine limestones belonging to the Kajlâka 
Formation of Latest Cretaceous age. Associated fossils and Sr isotopy suggest 
that the fossiliferous sediments belong to the uppermost part of the Upper 
Maastrichtian. The dinosaur bones discovered in this lens include the distal 
portion of a left femur, a right tibia, the proximal part of a right fibula, a 
left metatarsal II, the second or third phalanx of a left pedal digit IV, the 
proximal end of a second metacarpal, and a caudal centrum. All the bones 
undoubtedly belong to ornithopod dinosaurs and more accurately to 
representatives of the hadrosauroid clade. All belong to small-sized 
individuals, although it cannot be assessed whether they belong to juveniles or 
small-sized adults, pending histological analyses. Hadrosauroid remains have 
already been discovered in Late Maastrichtian marine sediments from western, 
central and eastern Europe, reflecting the abundance of these dinosaurs in 
correlative continental deposits. Indeed, hadrosauroids were apparently the 
dominating herbivorous dinosaurs in Eurasia by Late Maastrichtian time.

Eme, J., Gwalthney, J., Owerkowicz, T., Blank, J.M., and Hicks, J.W. 2010. 
Turning crocodilian hearts into bird hearts: growth rates are similar for 
alligators with and without right-to-left cardiac shunt. Journal of 
Experimental Biology 213(15):2673-2680. doi: 10.1242/jeb.042051.

ABSTRACT: The functional and possible adaptive significance of non-avian 
reptiles' dual aortic arch system and the ability of all non-avian reptiles to 
perform central vascular cardiac shunts have been of great interest to 
comparative physiologists. The unique cardiac anatomy of crocodilians – a 
four-chambered heart with the dual aortic arch system – allows for only 
right-to-left (R–L; pulmonary bypass) cardiac shunt and for surgical 
elimination of this shunt. Surgical removal of the R–L shunt, by occluding the 
left aorta (LAo) upstream and downstream of the foramen of Panizza, results in 
a crocodilian with an obligatory, avian/mammalian central circulation. In this 
study, R–L cardiac shunt was eliminated in age-matched, female American 
alligators (Alligator mississippiensis; 5–7 months of age). We tested the 
hypothesis that surgical elimination of R–L cardiac shunt would impair growth 
(a readily measured proxy for fitness) compared with sham-operated, age-matched 
controls, especially in animals subjected to exhaustive exercise. While regular 
exercise caused a decrease in size (snout-to-vent length, head length and body 
mass), elimination of the capacity for R–L cardiac shunt did not greatly reduce 
animal growth, despite a chronic ventricular enlargement in surgically altered 
juvenile alligators. We speculate that, despite being slightly smaller, 
alligators with an occluded LAo would have reached sexual maturity in the same 
breeding season as control alligators. This study suggests that crocodilian R–L 
cardiac shunt does not provide an adaptive advantage for juvenile alligator 
growth and supports the logic that cardiac shunts persist in crocodilians 
because they have not been selected against.

Kikuchi, R., and Vanneste, M. 2010. A theoretical exercise in the modeling of 
ground-level ozone resulting from the K-T asteroid impact: its possible link 
with the extinction selectivity of terrestrial vertebrates. Palaeogeography, 
Palaeoclimatology, Palaeoecology 288(1-4):14-23. doi: 

ABSTRACT: The extinction pattern of the Maastrichtian indicates that long-term 
and short-term events contributed to the Cretaceous–Tertiary (K–T) mass 
extinction at 65 Ma. However, it is not clear how the impact events are linked 
with the extinction selectivity; e.g. non-avian dinosaurs became extinct, 
whereas birds survived. The post-impact air quality is discussed, and attention 
is focused on the then land vertebrates. Although ground-level (tropospheric) 
O3 is a powerful irritant on the order of 0.1 ppm toxicity, the presence of 
ground-level O3  has hardly been considered since the K–T impact theory was 
reported about 30 years ago. Under the post-impact conditions reconstructed by 
simulating the carbon cycle (including isotope balance) and impact chemistry, a 
trajectory model suggests that the then photochemical reactions formed 
ground-level O3 whose concentration was apparently low at not, vert, similar 
1.0 ppm, but it is much greater than the current level of not, vert, similar 
0.04 ppm: that is, an O3 concentration above the health-threatening level 
persisted on the ground after the K–T impact. All land vertebrates must have 
suffered from respiratory O3 irritation at the time. However, analysis suggests 
that variables of O3 characteristics – hourly variation, short half-life in 
water and decomposition due to catalytic effects in soil – were randomly 
combined with variables of lifestyle features such as habitat, torpor, etc. to 
form new variables (i.e. survival rates): a high survival probability for 
amphibians; middle/high probabilities for semi-aquatic reptiles, mammals and 
birds; low/middle probabilities for marsupials and terrestrial reptiles; and a 
zero probability for non-avian dinosaurs.

Martin, T., Averianov, A.O., and Pfretzschner, H.-U. 2010. Mammals from the 
Late Jurassic Qigu Formation in the Southern Junggar Basin, Xinjiang, Northwest 
China pp. in Martin, T., Sun, G., and Mosbrugger, V. (eds.), Triassic-Jurassic 
Biodiversity, Ecosystems, and Climate in the Junggar Basin, Xinjiang, Northwest 

ABSTRACT: Five mammalian taxa based on teeth and jaw fragments are reported 
from a bonebed of the Late Jurassic (Oxfordian) Qigu Formation at the 
Liuhuanggou site in the southern Junggar Basin. The mammals recovered to date 
comprise a new eleutherodontid haramiyid, the docodonts Dsungarodon and 
Tegotherium, an undetermined amphilestid triconodont, and a new species of the 
stem zatherian Nanolestes and represent the most diverse Late Jurassic mammal 
assemblage of Asia. The Liuhuanggou mammal assemblage is dominated by 
docodonts. Acuodulodon Hu et al., 2007 from the upper part of the Shishugou 
Formation (Oxfordian) of the Wucaiwan area in the central Junggar Basin is a 
junior synonym of Dsungarodon Pfretzschner and Martin, 2005.i Tegotherium has 
been reported from the Late Jurassic Shar Teeg locality in Mongolia. With the 
exception of the common occurrence of Nanolestes, the mammalian assemblage from 
the Late Jurassic of the Guimarota coal mine (Portugal) is quite different from 
that of the Late Jurassic Qigu Formation. The Guimarota assemblage is dominated 
by five genera of dryolestidans and several genera of multituberculates, which 
have not been reported from the Qigu assemblage. The known Late Jurassic 
mammalian assemblages of Asia are similar to the Middle Jurassic assemblages 
known from Asia and elsewhere in the world. 

Namba, Y., Yamazaki, Y., Yuguchi, M., Kameoka, S., Usami, S., Honda, K., and 
Isokawa, K. 2010. Development of the tarsometatarsal skeleton by the lateral 
fusion of three cylindrical periosteal bones in the chick embryo (Gallus 
gallus). Anatomical Record. doi: 10.1002/ar.21179.

ABSTRACT: An avian tarsometatarsal (TMT) skeleton spanning from the base of 
toes to the intertarsal joint is a compound bone developed by elongation and 
lateral fusion of three cylindrical periosteal bones. Ontogenetic development 
of the TMT skeleton is likely to recapitulate the changes occurred during 
evolution but so far has received less attention. In this study, its 
development has been examined morphologically and histologically in the chick, 
Gallus gallus. Three metatarsal cartilage rods radiating distally earlier in 
development became aligned parallel to each other by embryonic day 8 (ED8). 
Calcification initiated at ED8 in the midshaft of cartilage propagated 
cylindrically along its surface. Coordinated radial growth by fabricating bony 
struts and trabeculae resulted in the formation of three independent bone 
cylinders, which further became closely apposed with each other by ED13 when 
the periosteum began to fuse in a back-to-back orientation. Bone 
microstructure, especially orientation of intertrabecular channels in which 
blood vasculature resides, appeared related to the observed rapid longitudinal 
growth. Differential radial growth was considered to delineate eventual surface 
configurations of a compound TMT bone, but its morphogenesis preceded the 
fusion of bone cylinders. Bony trabeculae connecting adjacent cylinders emerged 
first at ED17 in the dorsal and ventral quarters of intervening tissue at the 
mid-diaphyseal level. Posthatch TMT skeleton had a seemingly uniform 
mid-diaphysis, although the septa persisted between original marrow cavities. 
These findings provide morphological and histological bases for further 
cellular and molecular studies on this developmental process

Liutkus, C.M., Beard, J.S., Fraser, N.C., and Ragland, P.C. 2010. Use of 
fine-scale stratigraphy and chemostratigraphy to evaluate conditions of 
deposition and preservation of a Triassic Lagerstätte, south-central Virginia. 
Journal of Paleolimnology 44(2):645-666. doi: 10.1007/s10933-010-9445-1. 

ABSTRACT: The rich, fossiliferous Triassic sediments exposed in the Virginia 
Solite Quarry include a 34-mm-thick “insect layer” that is notable for detailed 
preservation of soft-bodied invertebrate and vertebrate remains. We describe 
this unique Konservat-Lagerstätte and use sedimentologic and geochemical 
analyses to interpret the environmental conditions necessary to preserve such 
delicate fossils. This work is among the first attempts to apply detailed 
geochemical/stratigraphic analysis to the study of Lagerstätten and we report 
on a 332-mm-thick section that includes the insect layer and the rocks 
immediately below and above it. Our analysis successfully constrains various 
aspects of the depositional and diagenetic history of the Lagerstätte  and 
permits a detailed analysis of changing conditions prior to, during, and after 
deposition. Geochemical and sedimentologic analyses of the insect layer and 
surrounding lithologies reveal a change from siliciclastic-dominated layers 
(Unit 1) to dolomite-siliciclastic laminites above (Unit 2 and the insect 
layer), separated by a boundary dolostone layer that is traceable for over 200 
m. We interpret this sedimentary shift as the initial stages in the 
transgression of a shallow, saline, alkaline rift-basin lake over lake margin 
deposits. The absence of bioturbation by plants and benthic organisms, as well 
as a lack of predation on the insects, is not explained by significant water 
depth, but is instead more reasonably considered a result of the chemistry of 
the water at the lake margin, affected by groundwater seeps, which provided F-, 
Mg-, and Ca-rich fluids. Although the initial conditions of preservation are 
remarkable, it is equally impressive that the fossils survived extensive 
diagenesis, e.g. dissolution of quartz and coarsening of dolomite. 

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

The way to a man's heart is through
his stomach.

                   -- old proverb

"The way to a man's heart is through
the fourth and fifth ribs."

                   -- Katchoo (and others)