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How the New Papers Was Won



.....aaaaaaaaand off we go!  Dinos first:

Remes, K. 2007. A second Gondwanan diplodocid dinosaur from the Upper Jurassic Tendaguru Beds of Tanzania, East Africa. Palaeontology 50(3):653-667. doi: 10.1111/j.1475-4983.2007.00652.x.

ABSTRACT: A new genus and species of diplodocid sauropod (Sauropoda, Diplodocoidea), Australodocus bohetii, is described. The type material from the Upper Jurassic (Tithonian) Tendaguru Beds of Tanzania, East Africa, consists of two successive mid-cervical vertebrae. These vertebrae do not show the extreme elongation of the cervical vertebrae that is diagnostic for Tornieria, and, apart from proportional differences, exhibit four autapomorphic characters not seen in other diplodocids: (1) pleurocoel weakly developed; (2) ridge posterolateral to the anterior condyle strongly posteroventrally orientated; (3) triangular pneumatic cavity ventral to the prezygapophysis, enclosed by the lateral ramus of the centroprezygapophyseal lamina and an anteriorly extended prezygodiapophyseal lamina; and (4) prominent prezygapophyseal process pointed, laterally keeled and surpassing the prezygapophysis anteriorly. Australodocus bohetii is the second diplodocid known from Tendaguru, and thereby the second diplodocid known from Gondwana. This impedes the customary reference of isolated East African diplodocid material to Tornieria, which can now only be assigned to Diplodocidae indet. The find supports previously proposed vicariance models of diplodocid palaeobiogeography.


Sánchez-Hernández, B., Benton, M.J., and Naish, D. 2007. Dinosaurs and other fossil vertebrates from the Late Jurassic and Early Cretaceous of the Galve area, NE Spain. Palaeogeography, Palaeoclimatology, Palaeoecology 249(1-2):180-215. doi: 10.1016/j.palaeo.2007.01.009.


ABSTRACT: Since 1950, diverse assemblages of Mesozoic vertebrates have been described from the Galve area (Teruel Province, NE Spain). More than fifty taxa have been noted, including fishes, crocodyliforms, pterosaurs, dinosaurs and mammals. The Galve fossil sites occur in an Upper Jurassic to Lower Cretaceous succession spanning some 30 myr, divided into five formations, representing marginal marine and continental settings, with a Tithonian-early Barremian regression and a transgression from the Barremian onwards. New discoveries include teeth of the hybodont shark Lonchidion microselachos, spinosaurine theropods, Eusauropoda and the dryosaurid Valdosaurus. The 30-myr succession shows some possible evolutionary shifts, with a predominance of sauropods as herbivores in older strata, and ornithopods commoner in younger beds. There are some possible replacements among mammals in the latter part of the succession, with trechnotheres, such as spalacotheriids and dryolestoids, dominant in the El Castellar Formation, and multituberculates in the Camarillas Formation. Matching of the vertebrates from the Galve succession with those from age-equivalent units throughout Europe shows close similarity with the Purbeck-Wealden succession of southern England, among others. There are many similarities with dinosaur faunas from North America and Africa, but continent-scale faunal differentiation had clearly begun.


Pereda Suberbiola, X., Ruiz-Omeñaca, J.I., Hernández, J.M., and Pujalte, V. 2006. Primera cita de un dinosaurio ornitópodo en el Cretácico Inferior (Berriasiense) del SO de la Cuenca Vasco-Cantábrica (Palencia, España). Revista de la Sociedad Geológica de España 19(3-4):219-231.


ABSTRACT: Ornithopod vertebral remains from the Lower Cretaceous of Aguilar de Campóo are the first dinosaur fossils to be found in the province of Palencia (Castilla y León). The material consists of fragmentary dorsal and caudal vertebrae that probably belong to a single medium-sized individual (about 4-5 m total length). The fossiliferous beds are red sandstones of fluvial origin from the Arcera Formation, which belongs to the Cabuérniga Group (SW margin of the Basque-Cantabrian Region), of Early Cretaceous age (late Berriasian). The vertebrae can be assigned to the Ornithopoda because the centra are amphiplatyan to slightly amphicoelous (posterior articular surface) and exhibit irregular neurocentral sutures. A morphometrical study suggests that the material belongs to an ornithopod close to Camptosaurus, and so it is provisionally referred to Camptosauridae indet. This interpretation is in agreement with the age of the outcrop. The Palencia discovery is one of the few ornithopod records from the basal Cretaceous of the Iberian Peninsula.


....then on to non-dinosaurian archosaurs:

Holliday, C.M., and Witmer, L.M. 2007. Archosaur adductor chamber evolution: integration of musculoskeletal and topological criteria in jaw muscle homology. Journal of Morphology 268(6):457-484. doi: 10.1002/jmor.10524.

ABSTRACT: The homologies of jaw muscles among archosaurs and other sauropsids have been unclear, confounding interpretation of adductor chamber morphology and evolution. Relevant topological patterns of muscles, nerves, and blood vessels were compared across a large sample of extant archosaurs (birds and crocodylians) and outgroups (e.g., lepidosaurs and turtles) to test the utility of positional criteria, such as the relative position of the trigeminal divisions, as predictors of jaw muscle homology. Anatomical structures were visualized using dissection, sectioning, computed tomography (CT), and vascular injection. Data gathered provide a new and robust view of jaw muscle homology and introduce the first synthesized nomenclature of sauropsid musculature using multiple lines of evidence. Despite the great divergences in cephalic morphology among birds, crocodylians, and outgroups, several key sensory nerves (e.g., n. anguli oris, n. supraorbitalis, n. caudalis) and arteries proved useful for muscle identification, and vice versa. Extant crocodylians exhibit an apomorphic neuromuscular pattern counter to the trigeminal topological paradigm: the maxillary nerve runs medial, rather than lateral to M. pseudotemporalis superficialis. Alternative hypotheses of homology necessitate less parsimonious interpretations of changes in topology. Sensory branches to the rictus, external acoustic meatus, supraorbital region, and other cephalic regions suggest conservative dermatomes among reptiles. Different avian clades exhibit shifts in some muscle positions, but maintain the plesiomorphic, diapsid soft-tissue topological pattern. Positional data suggest M. intramandibularis is merely the distal portion of M. pseudotemporalis separated by an intramuscular fibrocartilaginous sesamoid. These adductor chamber patterns indicate multiple topological criteria are necessary for interpretations of soft-tissue homology and warrant further investigation into character congruence and developmental connectivity.


Tumarkin-Deratzian, A.R., Vann, D.R., and Dodson, P. 2007. Growth and textural ageing in long bones of the American alligator Alligator mississippiensis (Crocodylia: Alligatoridae). Zoological Journal of the Linnean Society 150(1):1-39. doi: 10.1111/j.1096-3642.2007.00283.x.


ABSTRACT: Growth series of femora, tibiae, and humeri of the American alligator Alligator mississippiensis were examined to assess the relationship between bone surface textures and relative skeletal maturity. Element texture types were compared with both size-based and size-independent maturity estimates. Selected elements were thin sectioned to observe the histological structures underlying various surface textures. Results suggest little to no relationship between bone textures and skeletal maturity in Alligator. Controlling for additional factors suspected to affect textural variation - sexual dimorphism, seasonally interrupted growth, wild vs. captive habitat, and geographical range - provides little resolution. Indeterminate growth is almost certainly a factor; however, this alone cannot explain all observed variability. Histological analyses reveal that highly porous surface textures are often associated with zones composed of fibrolamellar bone; smoother textures are generally underlain by lamellar zones or annuli. Textures of intermediate porosity may be associated with more than one histological pattern. Until the factors affecting bone texture changes in modern crocodylians are better understood, it is recommended that the textural ageing method be applied with caution to studies of fossil archosaurs with crocodylian-like or unknown growth regimes.


...and then the little fuzzballs that were continually having to try and not be tromped into oblivion by dinosaurs:


Pascual, R., and Ortiz-Jaureguizar, E. 2007. The Gondwanan and South American episodes: two major and unrelated moments in the history of the South American mammals. Journal of Mammalian Evolution 14(2):75-137. doi: 10.1007/s10914-007-9039-5.

ABSTRACT: The first steps in the history of South American mammals took place ca. 130 Ma., when the South American plate, still connected to the Antarctic Peninsula, began to drift away from the African-Indian plate. Most of the Mesozoic history of South American mammals is still unknown, and we only have a few enigmatic taxa (i.e., a Jurassic Australosphenida and an Early Cretaceous Prototribosphenida) that pose more evolutionary and biogeographic questions than answers. The best-known Mesozoic, South American land-mammal fossils are from Late Cretaceous Patagonian beds. These fossils represent the last survivors of non- and pre-tribosphenic Pangaean lineages, all of them with varying endemic features: some with few advanced features (e.g., ?Eutriconodonta and "Symmetrodonta"), some very diversified as endemic groups (e.g., ?Docodonta Reigitheriidae), and others representing vicariant types of well known Laurasian Mesozoic lineages (e.g., Gondwanatheria as vicariant of Multituberculata). These endemic mammals lived as relicts (although advanced) of pangeic lineages when a primordial South American continent was still connected to the Antarctic Peninsula and, at the northern extreme, near the North American Plate. By the beginning of the Late Cretaceous, the volcanic and diastrophic processes that finally led to the differentiation of the Caribbean region and Central America built up transient geographic connections that permitted the initiation of an overland inter-American exchange that included, for example, dinosaurian titanosaurs from South America and hadrosaurs from North America. The immigration of other vertebrates followed the same route, for example, polydolopimorphian marsupials. These marsupials were assumed to have differentiated in South America prior to new discoveries from the North American Late Cretaceous. The complete extinction of endemic South American Mesozoic mammals by the Late Cretaceous-Early Paleocene, and the subsequent and in part coetaneous immigration of North American therians, respectively, represent two major moments in the history of South American mammals: a Gondwanan Episode and a South American Episode. The Gondwanan Episode was characterized by non- and pre-tribosphenic mammal lineages that descended from the Pangeic South American stage (but already with a pronounced Gondwanan accent, and wholly extinguished during the Late Cretaceous-Early Paleocene span). The South American Episode, in turn, was characterized only by therian mammals, mostly emigrated from the North American continent and already with a South American accent obtained through isolation. The southernmost extreme of South America (Patagonia) remained connected to the present Antarctic Peninsula at least up until about 30 Ma., and both provided the substratum where the primordial cladogenesis of "South American" mammals occurred. The resulting cladogenesis of South American therian mammals followed Gould's motto: early experimentation, later standardization. That is to say, early cladogenesis engendered a great variety of taxa with scarce morphological differentiation. After this early cladogenesis (Late Eocene-Early Oligocene), the variety of taxa became reduced, but each lineage became clearly recognizable distinctive by a constant morphologic pattern. At the same time, those mammals that underwent the "early experimentation" were part of communities dominated by archaic lineages (e.g., brachydont types among the native "ungulates"), whereas the subsequent communities were dominated by mammals of markedly "modern" stamp (e.g., protohypsodont types among the native "ungulates"). The Gondwanan and South American Episodes were separated by a critical latest Cretaceous-earliest Paleocene hiatus, it is as unknown as it is important in which South American land-mammal communities must have experienced extinction of the Gondwanan mammals and the arrival and radiation of the North American marsupials and placentals (with the probable exception of the xenarthrans, whose biogeographic origin is still unclear).

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

"Trying to estimate the divergence times
of fungal, algal or prokaryotic groups on
the basis of a partial reptilian fossil and
protein sequences from mice and humans
is like trying to decipher Demotic Egyptian with
the help of an odometer and the Oxford
English Dictionary."
-- D. Graur & W. Martin (_Trends
in Genetics_ 20[2], 2004)