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Cloudy With A Chance of New Papers



Sorry if any of these are duplicates of stuff already mentioned on the 
list...I've been in England and largely away from e-mail since SVP...!



Taylor, M.A. 2009. Electronic publication of nomenclatural acts is inevitable, 
and will be accepted by the taxonomic community with or without the endorsement 
of the Code. Bulletin of Zoological Nomenclature 66(3):205-214.



Murakami, M., Hirayama, R., Hikida, Y., and Hirano, H. 2009. A theropod 
dinosaur (Saurischia: Maniraptora) from the Upper Cretaceous Yezo Group of 
Hokkaido, northern Japan. Paleontological Research 12(4):421-425.




Sepúlveda, J., Wendler, J.E., Summons, R.E., and Hinrichs, K.-U. 2009. Rapid 
resurgence of marine productivity after the Cretaceous-Paleogene mass 
extinction. Sciencce 326:129-132. doi: 10.1126/science.1176233.

ABSTRACT: The course of the biotic recovery after the impact-related disruption 
of photosynthesis and mass extinction event at the Cretaceous-Paleogene 
boundary has been intensely debated. The resurgence of marine primary 
production in the aftermath remains poorly constrained because of the paucity 
of fossil records tracing primary producers that lack skeletons. Here we 
present a high-resolution record of geochemical variation in the remarkably 
thick Fiskeler (also known as the Fish Clay) boundary layer at Kulstirenden, 
Denmark. Converging evidence from the stable isotopes of carbon and nitrogen 
and abundances of algal steranes and bacterial hopanes indicates that algal 
primary productivity was strongly reduced for only a brief period of possibly 
less than a century after the impact, followed by a rapid resurgence of carbon 
fixation and ecological reorganization.




Schwarz-Wings, D., Meyer, C.A., Frey, E., Manz-Steiner, H.-R., and Schumacher, 
R. 2009. Mechanical implications of pneumatic neck vertebrae in sauropod 
dinosaurs. Proceedings of the Royal Society B: Biological Sciences. doi: 
10.1098/rspb.2009.1275.

ABSTRACT: The pre-sacral vertebrae of most sauropod dinosaurs were surrounded 
by interconnected, air-filled diverticula, penetrating into the bones and 
creating an intricate internal cavity system within the vertebrae. 
Computational finite-element models of two sauropod cervical vertebrae now 
demonstrate the mechanical reason for vertebral pneumaticity. The analyses show 
that the structure of the cervical vertebrae leads to an even distribution of 
all occurring stress fields along the vertebrae, concentrated mainly on their 
external surface and the vertebral laminae. The regions between vertebral 
laminae and the interior part of the vertebral body including thin bony struts 
and septa are mostly unloaded and pneumatic structures are positioned in these 
regions of minimal stress. The morphology of sauropod cervical vertebrae was 
influenced by strongly segmented axial neck muscles, which require only small 
attachment areas on each vertebra, and pneumatic epithelia that are able to 
resorb bone that is not mechanically loaded. The interaction of these soft 
tissues with the bony tissue of the vertebrae produced lightweight, air-filled 
vertebrae in which most stresses were borne by the external cortical bone. 
Cervical pneumaticity was therefore an important prerequisite for neck 
enlargement in sauropods. Thus, we expect that vertebral pneumaticity in other 
parts of the body to have a similar role in enabling gigantism.




Bhullar, B.-A.S., and Bever, G.S. 2009. An archosaur-like laterosphenoid in 
early turtles (Reptilia: Pantestudines). Breviora 518:1-11.

ABSTRACT: Turtles are placed with increasing consistency by molecular 
phylogenetic studies within Diapsida as sister to Archosauria, but published 
gross morphology?Cbased phylogenetic analyses do not recover this position. 
Here, we present a previously unrecognized unique morphological character 
offering support for this hypothesis: the presence in stem turtles of a 
laterosphenoid ossification identical to that in Archosauriformes. The 
laterosphenoid is a tripartite chondrocranial ossification, consisting of an 
ossified pila antotica, pila metoptica, and taenia medialis + planum 
supraseptale. It forms the anterior border of the exit for the trigeminal nerve 
(V) and partially encloses the exits for cranial nerves III, IV, and II. This 
ossification is unique to turtles and Archosauriformes within Vertebrata. It 
has been mistakenly dismissed as anatomically dissimilar in these two groups in 
the past, so we provide a complete description and detailed analysis of 
correspondence between turtles and Archosauriformes in each of its 
embryologically distinct components. A preliminary phylogenetic analysis 
suggests other potential  synapomorphies of turtles and archosaurs, including a 
row or rows of mid-dorsal dermal ossifications.




Knight, T.K., Bingham, S., Grimaldi, D.A., Anderson, K., Lewis, R.D., and 
Savrda, C.E. 2009. A new Upper Cretaceous (Santonian) amber deposit from the 
Eutaw Formation of eastern Alabama, USA. Cretaceous Research. doi: 
10.1016/j.cretres.2009.09.008.

ABSTRACT: A new amber-rich deposit has been identified in the Upper Cretaceous 
(Santonian) Eutaw Formation exposed in eastern Alabama, U.S.A. Amber occurs as 
common parautochthonous clasts and in direct association with conifer plant 
parts in the lower part of a thin, laterally discontinuous, carbonaceous and 
pyritiferous clay lens that was deposited in a tidal channel within a 
transgressive estuarine bayhead-delta system. Organic inclusions are common in 
amber clasts and include plant and fungal debris and terrestrial arthropod 
remains. The latter include mites, a spider in association with its web, and 
scale insects. Amber-plant associations and amber geochemistry indicate that 
resins were derived from the Cupressaceae, virtually identical to the trees 
that produced the Turonian-aged amber from central New Jersey, USA.




Kusuhashi, N., Hu, Y., Wang, y., Hirasawa, S., and Matsuoka, H. 2009. New 
triconodontids (Mammalia) from the Lower Cretaceous Shahai and Fuxin 
formations, northeastern China. Geobios. doi: 10.1016/j.geobios.2009.06.003.

ABSTRACT: The first triconodontids from Asia have been discovered from the 
Lower Cretaceous (Aptian to Albian) Shahai and Fuxin formations in Liaoning 
Province, northeastern China: Meiconodon lii gen. and sp. nov. and M. 
setoguchii gen. and sp. nov. Meiconodon lii is characterized by molariform 
teeth with a developed cusp d, an m3 with taller cusp a, an m4 with three 
primary cusps of subequal height, the posteriorly decreasing transverse width 
of the m4, and a considerably reduced m5. Meiconodon setoguchii is slightly 
larger than M. lii, and characterized by a sharp labial cingulum on the m4, and 
a less developed cusp d on the molariform teeth than M. lii. The extensive 
interlocking system between molariforms, posteriorly recumbent primary 
molariform cusps, and their great degree of asymmetry in occlusal view with 
rounded labial faces and more angulate lingual faces in lateral view, indicate 
that Meiconodon belongs to the triconodontid subfamily Alticonodontinae. These 
new taxa are the first record of Triconodontidae from Asia, and of 
Alticonodontinae outside North America, suggesting the occurrence of mammalian 
faunal exchange between North America and Asia during or before the 
Aptian-Albian.




Knoll, F. 2009. A large iguanodont from the upper Barremian of the Paris Basin. 
Geobios. doi: 10.1016/j.geobios.2009.06.002.

ABSTRACT: The remains of an ornithopod dinosaur from the Upper Barremian (Lower 
Cretaceous) of Auxerre (Burgundy, France) are described. They consist of 
several vertebrae and a fragmentary scapula. Despite obvious morphological and 
dimensional affinities with the species Iguanodon bernissartensis , the state 
of the specimen does not allow any identification more precise than 
Iguanodontia indet . Reappraisal of the French Upper Barremian record of 
medium-sized and large ornithopods reveals that no specimen can be definitely 
determined to the specific level.




Prauss, M.L. 2009. The K/Pg boundary at Brazos-River, Texas, USA -- an approach 
by marine palynology. Palaeogeography, Palaeoclimatology, Palaeoecology. doi: 
10.1016/j.palaeo.2009.09.024.

ABSTRACT: Two cores and one outcrop section from the Cretaceous/Palaeogen 
(K/Pg) boundary interval at the Brazos-River area, Texas, USA, have been high 
resolution sampled and analysed fully quantitatively by marine palynology. The 
results have been compared and integrated with data from micropalaeontology, 
sedimentology and isotope-geochemistry from the same sections. Within all three 
sections, the K/Pg boundary, defined as the base of the P0 foraminifera zone 
and the onset of a negative carbon isotope anomaly, closely corresponds to the 
appearance of lowermost Danian organic-walled dinocysts. Based on various 
palynological proxies as well as on sedimentologic features, a sequence 
stratigraphic subdivision of the sections is proposed. From a synopsis of all 
three sections, a long term, punctuated drop of relative sea-level is 
indicated, starting at about the top of the Upper Cretaceous CF2 foraminifera 
zone and reaching a minimum within the upper P1a zone of the Lower Palaeogene. 
This is followed by a prominent transgression starting within the P1a/P1b 
boundary interval. The “event deposit” (ED), a siliciclastic unit located well 
below the base of the P0 foraminifera zone in the present sections, most 
probably represents a combination of both episodic relative sea-level fall and 
lag deposit due to initial transgression. It is preceded by significant 
fluctuations of climatic boundary conditions, with cool climates correlating to 
heavier δ 13C values and increased p/g ratio of dinocysts, suggestive of higher 
marine primary productivity. Across the K/Pg boundary, a prominent increase and 
spike of the warm-temperate waters dinocysts fraction is documented, 
represented mainly by Trithyrodinium evittii, which is accompanied by climatic 
warming and an episodic relative sea-level rise. Thus, prominent 
paleo-environmental changes and sea-level fluctuations precede and coincide 
with the K/Pg boundary proper. These data are inconsistent with a single 
“catastrophic” impact as the cause for the K/Pg boundary eve!
nt, but s
uggest relative longer term environmental stress as finally leading to 
End-Cretaceous crisis of the biosphere. Between the ED and the K/Pg boundary 
proper, the gradual increase to peak abundance in trilete spores demonstrates a 
significant time lag between these two horizons. According to the distinct 
distribution of this peak abundance, it cannot be excluded that an 
impact/tsunami event is related to the lower portion of the ED. In contrast, no 
significant changes within most palynologic proxies are documented across the 
yellow clay layer below the ED documented within one of the sections and 
recently suggested as the original Chicxulub impact ejecta horizon. This 
questions the impact origin of this horizon or, at least, suggests only little 
consequences of this event on the ecosystem.




Roberts, E.M., O'Connor, P.M., Stevens, N.J., Gottfried, M.D., Jinnah, Z.A., 
Ngasala, S., Choh, A.M., and Armstrong, R.A. 2009. Sedimentology and 
depositional environments of the Red Sandstone Group, Rukwa Rift Basin, 
southwestern Tanzania: new insight into Cretaceous and Paleogene terrestrial 
ecosystems and tectonics in sub-equatorial Africa. Journal of African Earth 
Sciences. doi: 10.1016/j.jafrearsci.2009.09.002

ABSTRACT: The Red Sandstone Group (RSG) in the Rukwa Rift Basin of southwestern 
Tanzania represents one of the only well-exposed, fossiliferous 
Cretaceous-Paleogene continental sedimentary sequences in sub-equatorial 
Africa. The significance of the RSG for reconstructing the paleoenvironmental 
and paleoclimatic history of African ecosystems during these critical time 
periods has been obfuscated by long-standing confusion and debate over the age 
of the deposits. Detailed stratigraphic, sedimentologic, and paleontologic 
investigations of the RSG conducted between 2002 and 2008 have produced a 
wealth of new fossil discoveries and data on lithofacies, alluvial 
architecture, sedimentary provenance, clay mineralogy and geochronology that 
resolve the long-standing debate over the age of these deposits. This study 
confirms the existence of an extensive middle Cretaceous sequence, herein named 
the Galula Formation, and subdivided into the Mtuka and Namba members. 
Moreover, we document the existence of a previously unrecognized late Paleogene 
continental sequence termed the Nsungwe Formation, which is divided into the 
Utengule and Songwe members. The Galula Formation represents a 600-3000 m thick 
sequence of amalgamated, braided fluvial deposits that were deposited across a 
large braidplain system via multiple parallel channels that had their source in 
the highlands of Malawi and Zambia. The middle Cretaceous Dinosaur Beds of 
Malawi are hypothesized to be at least partially correlative with the Galula 
Formation, and represent proximal deposits of this large, northwest flowing, 
trunk stream system. A moderately diverse terrestrial vertebrate fauna, 
including multiple species of dinosaurs, crocodyliforms, turtles, fishes and 
mammals have been recovered, along with a sparse aquatic molluscan fauna. 
Lithofacies and clay mineralogy indicate that Cretaceous paleoclimate 
ameliorated during deposition of the Galula Formation, transitioning from 
tropical semi-arid to tropical humid conditions.
     The 400+ m-thick late Oligocene Nsungwe Formation is temporally 
constrained by concordant mammalian biostratigraphy, detrital zircon 
geochronology and a radiometrically dated volcanic tuff capping the sequence 
(not, vert, similar24.9 Ma). A significant change in depositional environments 
occurs between the lower alluvial fan-dominated Utengule Member and the upper 
fluvial and lacustrine-dominated Songwe Member. The Songwe Member preserves a 
diverse terrestrial and aquatic vertebrate and invertebrate fauna, with 
abundant ashfall and ashflow volcanic tuffs that were deposited in a semi-arid 
wetland landscape during the late Oligocene. The Nsungwe Formation provides a 
new window into the early tectonics and faunal transitions associated with 
initiation of the “Modern” East African Rift System.




Ji, Q., Luo, Z.-X., Zhang, X., Yuan, C.-X., and Xu, L. 2009. Evolutionary 
development of the middle ear in Mesozoic therian mammals. Science 326:278-281. 
doi: 10.1126/science.1178501.

ABSTRACT: The definitive mammalian middle ear (DMME) is defined by the loss of 
embryonic Meckel's cartilage and disconnection of the middle ear from the 
mandible in adults. It is a major feature distinguishing living mammals from 
nonmammalian vertebrates. We report a Cretaceous trechnotherian mammal with an 
ossified Meckel's cartilage in the adult, showing that homoplastic evolution of 
the DMME occurred in derived therian mammals, besides the known cases of 
eutriconodonts. The mandible with ossified Meckel's cartilage appears to be 
paedomorphic. Reabsorption of embryonic Meckel's cartilage to disconnect the 
ear ossicles from the mandible is patterned by a network of genes and signaling 
pathways. This fossil suggests that developmental heterochrony and gene 
patterning are major mechanisms in homplastic evolution of the DMME.




Elzanowski, A., and Stidham, T.A. 2009. Morphology of the quadrate in the 
Eocene anseriform Presbyornis and extant galloanserine birds. Journal of 
Morphology. doi: 10.1002/jmor.10799.

ABSTRACT: Despite the notoriety, phylogenetic significance, and large number of 
available specimens of Presbyornis, its cranial anatomy has never been studied 
in detail, and its quadrate has been partly misinterpreted. We studied five 
quadrates of Presbyornis that reveal features hitherto unknown in the 
anseriforms but otherwise present in galliforms. As a result, we analyzed the 
variable quadrate characters among all extant galloanserine families and 
identified synapomorphies and other morphological variation among the major 
galloanserine clades. In terms of quadrate morphology, Presbyornis is more 
plesiomorphic than any extant anseriform (including the Anhimidae) and shares 
ancestral galloanserine characters with the Megapodiidae, the earliest branch 
of extant galliforms. The quadrate's morphology is inconsistent with the 
currently accepted anseriform phylogeny that nests Presbyornis within the 
crown-group as a close relative of the Anatidae. The presbyornithid quadrates 
exhibit an unusual variation in the presence of a caudomedial pneumatic 
foramen, which we interpret as a result of a discontinuous change in the growth 
path of the pneumatic diverticulum. Another episode of morphogenetic imbalance 
in the growth path of the pneumatic diverticulum may have accompanied the 
disappearance of the basiorbital pneumatic foramen (along with the 
pneumatization of the pterygoid) at the origin of the crown-group anseriforms. 
This episode is marked by the striking individual variation in the presence and 
location of pneumatic foramina in the mandibular part of the quadrate in the 
Anhimidae.




Senter, P. 2009. Vestigial skeletal structures in dinosaurs. Journal of 
Zoology. doi: 10.1111/j.1469-7998.2009.00640.x.

ABSTRACT: The existence of vestigial structures is one of the main lines of 
evidence for macroevolution. Here I introduce a phylogenetic bracketing 
approach to the identification of vestigial structures and apply it to 
Dinosauria. According to this approach, a structure is considered vestigial if, 
in comparison with its homolog in at least three successive outgroups, it is 
reduced to one-third or less its size relative to adjacent structures and if at 
least distally it has lost the specialized morphology present in the three 
outgroups. This approach identifies fingers IV and V as vestigial in dinosaurs 
in general, II?CV in sauropods, III in Tyrannosauridae and Caudipteryx, II and 
III in Shuvuuia and I and III in modern birds. The entire forelimb distal to 
the elbow is vestigial in Abelisauridae. Vestigial parts of the pelvic girdle 
and hindlimb include the pubic shaft in Iguanodontia and Ceratopsia, the entire 
pubis in Ankylosauria, the first metatarsal in derived Iguanodontia, the first 
metatarsal shaft in Theropoda and the fifth toe in dinosaurs in general. 
Derived Centrosaurinae and some Chasmosaurus exhibit vestigial supraorbital 
horns. Some centrosaurines have a vestigial nasal horn. The antorbital cavity 
is vestigial in Thyreophora, Iguanodontia and Ceratopsidae. I recommend that 
this information be exploited to increase public awareness of the evidence for 
macroevolution.




Vargas, A.O., Wagner, G.P., and Gauthier, J.A. 2009. Limusaurus and bird digit 
identity. Nature Precedings.

ABSTRACT: Limusaurus is a remarkable herbivorous ceratosaur unique among 
theropods in having digits II, III and IV, with only a small metacarpal vestige 
of digit I. This raises interesting questions regarding the controversial 
identity of avian wing digits. The early tetanuran ancestors of birds had 
tridactyl hands with digital morphologies corresponding to digits I, II & III 
of other dinosaurs. In bird embryos, however, the pattern of cartilage 
formation indicates that their digits develop from positions that become digits 
II, III, & IV in other amniotes. Limusaurus has been argued to provide evidence 
that the digits of tetanurans, currently considered to be I, II and III, may 
actually be digits II, III, & IV, thus explaining the embryological position of 
bird wing digits. However, morphology and gene expression of the anterior bird 
wing digit specifically resemble digit I, not II, of other amniotes. We argue 
that digit I loss in Limusaurus is derived and thus irrelevant to understanding 
the development of the bird wing.






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

"Education is the only thing people
shell out a lot of money for...and
then do everything possible to avoid
getting their money's worth."

                            -- unknown