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Dude, Where's My New Papers?

I know that the new ish of JVP has already been mentioned on list, but citations of the actual papers that I think might be of interest to list readers haven't yet, so here they are for anyone that needs them (more new papers below!):

Voigt, S., Berman, D.S., and Henrici, A.C. 2007. First well-established track-trackmaker association of Paleozoic tetrapods based on Ichniotherium trackways and diadectid skeletons from the Lower Permian of Germany. Journal of Vertebrate Paleontology 27(3):553-570. doi: 10.1671/0272-4634(2007)27[553:FWTAOP]2.0.CO;2.

ABSTRACT: As a single stratigraphic source and site of high-fidelity vertebrate trackways and superbly preserved skeletons, the Lower Permian Tambach Formation, lowermost unit of the Upper Rotliegend, of the Bromacker locality in the middle part of the Thuringian Forest near Gotha, central Germany, provides a unique opportunity of matching late Paleozoic trackways with their trackmakers. Here the track-trackmaker association is firmly established between two species of the ichnogenus Ichniotherium, Ichniotherium cottae and Ichniotherium sphaerodactylum, and the skeletal fossils of the closely related diadectids Diadectes absitus and Orobates pabsti, respectively. These are the first well-documented species-level identifications of the trackmakers of Paleozoic trackways. The Ichniotherium ichnospecies are principally separated by the relative lengths of the digits of the pes imprint and the degree of overstepping of the pes and manus imprints. Both characters are shown to be clearly due to differences in the number and lengths of phalangeal elements and the number of presacral vertebrae of the diadectid species. The unique methods employed here in establishing the track-trackmaker associations provide not only an innovative data source for studying the evolutionary biology, paleo-biogeography, and locomotor behaviour of the trackmakers, but also a valuable methodology for evaluating taxonomic concepts in vertebrate ichnology.

Prieto-Marquez, A., Gignac, P.M., and Joshi, S. 2007. Neontological evaluation of pelvic skeletal attributes purported to reflect sex in extinct non-avian archosaurs. Journal of Vertebrate Paleontology 27(3):603-609. doi: 10.1671/0272-4634(2007)27[603:NEOPSA]2.0.CO;2.

ABSTRACT: Sex in non-avian archosaurs has been inferred using a variety of osteological attributes. However, little quantitative data have been presented showing that these phenotypes truly exist. In this study, testing for the presence of pelvic osteological correlates of sex in extant archosaurs was conducted, using skeletons of wild-caught A. mississippiensis as a neontological model. For outgroup comparison, the squamate Iguana iguana is included. A sample of 16 females and 19 males of A. mississippiensis, and 18 females and 10 males of I. iguana were examined. Measurements included pelvic canal area, dorsoventral depth, and mediolateral width of the pelvic canal, mediolateral width between the dorsal edge of each ilium, and ischium orientation. These data were analyzed using analyses of covariance, a t-test, and a recently developed geodesic distance shape analysis. Results indicate that there is sexual dimorphism in the proportions of the pelvic canal in A. mississippiensis, with females typically having deeper pelvic canals than males. This dimorphism might be synapomorphic for Archosauria. No dimorphism was found in I. iguana. The detection of dimorphism in A. mississipiensis required large sample sizes owing to substantial overlap between sexes. Thus, sexing isolated specimens using this metric is tenuous at best. Assuming similar variance in the relative pelvic depth versus width in other non-avian archosaurs, this criterion would also produce imprecise determinations of sex for these taxa.

Allain, R., Tykoski, R., Aquesbi, N., Jalil, N.-E., Monbaron, M., Russell, D., and Taquet, P. 2007. An abelisauroid (Dinosauria: Theropoda) from the Early Jurassic of the High Atlas Mountains, Morocco, and the radiation of ceratosaurs. Journal of Vertebrate Paleontology 27(3):610-624. doi: 10.1671/0272-4634(2007)27[610:AADTFT]2.0.CO;2.

ABSTRACT: The fossil record of abelisauroid carnivorous dinosaurs was previously restricted to Cretaceous sediments of Gondwana and probably Europe. The discovery of an incomplete specimen of a new basal abelisauroid, Berberosaurus liassicus, gen. et sp. nov., is reported from the late Early Jurassic of Moroccan High Atlas Mountains. Phylogenetic analysis recovers Ceratosauroidea and Coelophysoidea as sister lineages within Ceratosauria, and Berberosaurus as a basal abelisauroid. Berberosaurus is the oldest known abelisauroid and extends the first appearance datum of this lineage by about 50 million years. The taxon bridges temporal, morphological, and phylogenetic gaps that have hitherto separated Triassic to Early Jurassic coelophysoids from Late Jurassic through Cretaceous ceratosauroids. The discovery of an African abelisauroid in the Early Jurassic confirms at least a Gondwanan distribution of this group long before the Cretaceous.

Chinnery, B.J., and Horner, J.R. 2007. A new neoceratopsian dinosaur linking North American and Asian taxa. Journal of Vertebrate Paleontology 27(3):625-641. doi: 10.1671/0272-4634(2007)27[625:ANNDLN]2.0.CO;2.

ABSTRACT: Basal (cladistically) neoceratopsians are relatively small, gracile members of Ceratopsia ('horned' dinosaurs), which also includes larger forms such as Triceratops and Centrosaurus. The Asian basal neoceratopsians share some very important traits not found in any North American group until now, including a fenestrated frill and premaxillary teeth. Likewise, the North American basal taxa have some traits not found in the Asian forms, the most important of which is a very specialized tooth wear pattern. Cerasinops hodgskissi, a new basal neoceratopsian from the Lower Two Medicine River Formation of Montana, exhibits all of the above characters along with others previously found on only one of the two continents. The new species is a sister group to Leptoceratopsidae in a cladistic analysis, and is a link between the taxa on the two continents. Cerasinops also exhibits extremely interesting anatomical and histological features that indicate the possibility of bipedality in this taxon, a locomotor pattern not found previously in basal neoceratopsians (it has been suggested in some, but with little evidence).

Evans, D.C., Reisz, R.R., and Dupuis, K. 2007. A juvenile Parasaurolophus (Ornithischia: Hadrosauridae) braincase from Dinosaur Provincial Park, Alberta, with comments on crest ontogeny in the genus. Journal of Vertebrate Paleontology 27(3):642-650. doi: 10.1671/0272-4634(2007)27[642:AJPOHB]2.0.CO;2.

ABSTRACT: An incomplete braincase of a juvenile lambeosaurine hadrosaurid (Dinosauria: Ornithischia) is recognized as the second and smallest cranial specimen of Parasaurolophus from the Belly River Group (Campanian), Alberta, Canada. This specimen provides the first information on the ontogeny of the skull roof and autapomorphic tubular crest in this widely recognized yet poorly known taxon. In addition to the distinctive morphology of the cranial crest, Parasaurolophus is characterized by a suite of skull roof characters associated with crest development that manifest at small size, including verticalization of the nasal frontal joint at the base of the crest. Although the crest is not preserved in the specimen described here, the distinctively thickened and steeply angled frontal platform indicates that the crest and facial profile were significantly different from the equivalent juvenile stages of corythosaurin lambeosaurines (Corythosaurus, Hypacrosaurus, Lambeosaurus), which resemble one another closely. Parasaurolophus therefore appears to deviate from the well-known corythosaurin mode of cranial crest growth early in ontogenetic development.

Averianov, A.O., Leshchinskiy, S.V., Kudryavtsev, V.I., and Zabelin, V.I. 2007. Braincase of a Late Jurassic stegosaurian dinosaur from Tuva, Russia (central Asia). Journal of Vertebrate Paleontology 27(3):727-733. doi: 10.1671/0272-4634(2007)27[727:BOALJS]2.0.CO;2. ABSTRACT:

Reisz, R.R., and Modesto, S.P. 2007. Heleosaurus scholtzi from the Permian of South Africa: a varanopid synapsid, not a diapsid reptile. Journal of Vertebrate Paleontology 27(3):734-739. doi: 10.1671/0272-4634(2007)27[734:HSFTPO]2.0.CO;2. ABSTRACT:

Then, some other new papers...the Dubois one is the kind of horrible thing that gives me a headache...:

Botha-Brink, J., and Modesto, S.P. 2007. A mixed-age classed 'pelycosaur' aggregation from South Africa: earliest evidence of parental care in amniotes? Proceedings of the Royal Society of London B. doi: 10.1098/rspb.2007.0803.

ABSTRACT: Living species of mammals, crocodiles and most species of birds exhibit parental care, but evidence of this behaviour is extremely rare in the fossil record. Here, we present a new specimen of varanopid 'pelycosaur' from the Middle Permian of South Africa. The specimen is an aggregation, consisting of five articulated individuals preserved in undisturbed, close, lifelike, dorsal-up, subparallel positions, indicating burial in 'life position'. Two size classes are represented. One is 50% larger than the others, is well ossified, has fused neurocentral sutures and is distinguished by a coat of dermal ossifications that covers the neck and shoulder regions. We regard this individual to be an adult. The remaining four skeletons are considered to be juveniles as they are approximately the same size, are poorly ossified, have open neurocentral sutures and lack dermal ossifications. Aggregates of juvenile amniotes are usually siblings. Extant analogues of adult and juvenile groupings suggest that the adult is one of the parents, leading us to regard the aggregation as a family group. The Late Middle Permian age of the varanopid family predates the previously known oldest fossil evidence of parental care in terrestrial vertebrates by 140Myr.

Dubois, A. 2007. Naming taxa from cladograms: a cautionary tale. Molecular Phylogenetics and Evolution 42(2):317-330. doi: 10.1016/j.ympev.2006.06.007.

ABSTRACT: The recent publication of a new hypothesis of cladistic relationships among American frogs referred to the genus Rana, accompanied by a new taxonomy and a new nomenclature of this group [Hillis D.M., Wilcox, T.P., 2005. Phylogeny of the New World true frogs (Rana). Molecular Phylogenetics and Evolution 34, 299-314], draws attention to the problems posed by the use of a "double nomenclature", following both the rules of the International Code of Zoological Nomenclature (designated here as "onomatophore-based nomenclature") and the rules of the draft Phylocode (designated here as "definition-based nomenclature"). These two nomenclatural systems, which rely upon widely different theoretical bases, are incompatible, and the latter cannot be viewed as a "modification" of the former. Accordingly, scientific names (nomina) following both systems should be clearly distinguished in scientific publications. Onomatophore-based nomina should continue to be written as they have been for about 250 years, whereas definition-based nomina should be written in a specific way, e.g., <Lithobates>. The combined use of both nomenclatural systems for the same taxonomy in the same paper requires good knowledge and careful respect of the rules of the Code regarding availability, allocation and validity of nomina. As shown by this example, not doing so may result in various problems, in particular in publishing nomina nuda or in using nomenclatural ranks invalid under the current Code. Attention is drawn to the fact that new nomina published without diagnostic characters are not available under the Code, and that the latter currently forbids the use of more than two ranks (subgenus and "aggregate of species") between the ranks genus and species.

(note here that this abstract doesn't read quite correctly because of the plain-text-only ability of the list serv -- of importance is how his parenthetical "(Lithobates)" appears in the original abstract: the word is in small caps (first letter capitalized, of course), and it is surrounded by a peculiar variant of parentheses that consist of two angled lines, wider than < or > symbols.)

Lislevand, T., Figuerola, J., and Székely, T. 2007. Avian body sizes in relation to fecundity, mating system, display behavior, and resource sharing. Ecology 88(6):1605. doi: 10.1890/06-2054.

ABSTRACT: Body size is an important characteristic of animals, influencing physiology, life histories, and general ecology. Hence, it often needs to be taken into account even if the aim is to test for relationships among other traits. We provide a comprehensive data set on avian body sizes that would be useful for future comparative studies of avian biology. We extracted species-specific measurements on male and female body mass, wing length, tarsus length, bill length, and tail length from major ornithological text books and some other sources covering bird species of Africa, Australia, New Zealand, Antarctica, North America, and the western Palearctic. These measurements were matched with measures of egg and clutch sizes, and scores of mating system, sexual display agility, and the degree of intersexual resource division. We present morphometric data ranging from 2350 species (minimum, tail length) to 2979 species (maximum, wing length) where measurements for both sexes are known, some additional data where only one sex or unsexed birds have been measured, and explanatory data ranging from 1218 species (minimum, display agility) to 2603 species (maximum, egg mass). In total, 3769 species from 125 of 146 different bird families are included. We have used the data in comparative studies of avian sexual size dimorphism, where we test adaptive hypotheses concerning the influence of sexual selection, fecundity, and the degree of within-pair resource sharing. By publishing the data we intend to give easy access to a large data set containing variables relevant for a wide range of comparative studies on birds, thus saving researchers from the time- and resource-consuming data gathering process. In addition, the data set will function to point out species where baseline data on body size and relevant information on reproduction and behavior are currently lacking or of poor quality, thus stimulating the publication of such data.

Rieppel, O. 2007. The performance of morphological characters in broad-scale phylogenetic analyses. Biological Journal of the Linnean Society 92(2):297-308. doi: 10.1111/j.1095-8312.2007.00847.x.

ABSTRACT: In view of their propositional content (i.e. they can be right or wrong), character statements (i.e. statements that predicate characters of organisms) are treated as low-level hypotheses. The thesis of the present study is that such character statements, as do more complex scientific theories, come with variable scope. The scope of a hypothesis, or theory, is the domain of discourse over which the hypothesis, or theory, ranges. A character statement is initially introduced within the context of a certain domain of discourse that is defined by the scale of the initial phylogenetic analysis. The doctrine of 'total evidence' requires the inclusion of previously introduced characters in subsequent studies. As a consequence, the initial scope of character statements is widened to the extent that the scale of subsequent analyses is broadened. Scope expansion for character statements may result in incomplete characters, in the subdivision of characters, or in ambiguity of reference (indeterminacy of the extension of anatomical terms). Character statements with a wide scope are desirable because they refer to characters with the potential to resolve deep nodes in phylogenetic analyses. Care must be taken to preserve referential unambiguity of anatomical terms if the originally restricted scope of a character statement is expanded to match a broad-scale phylogenetic analysis.

Hall, M.I., and Ross, C.F. 2007. Eye shape and activity pattern in birds. Journal of Zoology 271(4):437-444. doi: 10.1111/j.1469-7998.2006.00227.x.

ABSTRACT: Many aspects of an animal's ecology are associated with activity pattern, the time of day when that animal is awake and active. There are two major activity patterns: diurnal, active during the day in a light-rich, or photopic, environment, and nocturnal, active after sunset in a light-limited, or scotopic, environment. Birds are also cathemeral, or equally likely to be awake at any time of day, or crepuscular, awake and active at dawn and dusk. Each of these activity patterns is associated with different levels of ambient light. This study examines how the morphology (size and shape) of the eye varies according to these different light environments for birds in a phylogenetic context. Activity pattern has a significant influence on eye shape and size in birds. Birds that are adapted for scotopic vision have eye shapes that are optimized for visual sensitivity, with larger corneal diameters relative to axial lengths. Birds that are adapted for photopic vision have eye shapes that are optimized for visual acuity, with larger axial lengths relative to corneal diameters. Birds adapted for scotopic vision also exhibit absolutely larger corneal diameters and axial lengths than do photopic birds. The results indicate that the light level under which the bird functions has a more significant influence on eye shape than phylogeny.

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


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