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New papers




First up, a salvo against the BANDits... However, Feduccia &c appear now to be arguing that birds and maniraptorans are indeed closely related, but that they are NOT theropods or dinosaurs. This is a load of codswallop, of course, but it may require a new tactic in refuting their arguments (e.g., demonstrating that you cannot remove Maniraptora from the Theropoda, any more than you can take Aves out of Maniraptora).


Chiappe, L.M. (2004). The closest relatives of birds. Ornitologia Neotropical. 15(Suppl. S): 101-116

ABSTRACT: "The origin of birds, the clade originating from the common ancestor of the Late Jurassic _Archaeopteryx_ and extant birds, has been at the center of a heated debate throughout the history of evolutionary biology. Although many disparate hypotheses of bird origins have been proposed in the last two centuries, an overwhelming consensus exists in support of the idea that birds evolved from maniraptoran theropod dinosaurs. Osteological support for this hypothesis is plentiful. The skeletons of such maniraptoran dinosaurs as dromaeosaurids, troodontids, and oviraptorids, share a great deal of similarity with those of birds. In addition, a series of spectacular discoveries in the last decade has provided new lines of evidence that supplement the already overwhelming osteological data. This recent evidence is derived primarily from the study of egg morphology and integumentary anatomy but also includes behavioral inferences based on a handful of rare fossils. These discoveries have documented the presence of feathers, brooding behavior, autochronous ovideposition, and other avian attributes among basal maniraptoran dinosaurs. The available evidence strongly supports the classification of birds within theropods and indicates that many avian attributes previously thought to be unique to birds (from brooding behavior to flight) first evolved among maniraptoran dinosaurs. Although dissenters of the Maniraptoran hypothesis of bird origins have countered by highlighting temporal and developmental limitations, these criticisms are clearly spurious. The most frequently voiced arguments, the so called "temporal paradox" and the homology of the digits of the avian hand, are tainted by logical inconsistencies. Perhaps the most important is the fact that these dissenters have been unable to produce alternative phylogenetic hypotheses that could explain, within the methodological framework of cladistic parsimony, the vast amount of similarity between non-avian theropods and birds."

A hadrosaur paper...

Mulder, E.W.A., Jagt, J.WM and Schulp, A.S (2005). Another record of a hadrosaurid dinosaur from the Maastrichtian type area (The Netherlands, Belgium): SEELEY (1883) revisited. Bulletin de l'Institut Royal des Sciences Naturelles de Belgique Sciences de la Terre. 75: 201-206.

ABSTRACT: "An incomplete left tibia of an indeterminate hadrosaurid from the type area of the Maastrichtian Stage, contained in the collections of the Museum fur Naturkunde der Humboldt-Universitat Berlin (ex Binkhorst van den Binkhorst Colln), is described, illustrated and compared with the type lot of _Orthomerus dolloi_ SEELEY, 1883 [nomen dubium]. Although the specimen lacks geographic/stratigraphic details, a small matrix sample taken from the medullar foramen has now yielded benthic foraminifera that corroborate its provenance from the Maastrichtian type area, and Suggest it to have originated from the upper portion of the Maastricht Formation (Emael or Nekum members)."

And when you gotta go, you gotta go...

Fernandes, M.A., Dos Reis Fernandes, L.B. and De Figueiredo Souto, P.R. (2004). Occurrence of urolites related to dinosaurs in the lower Cretaceous of the Botucatu Formation, Parana basin, Sao Paulo State, Brazil. Revista Brasileira de Paleontologia. 7(2): 263-268.

ABSTRACT: "The geological units that correspond to the Mesozoic in the Parana basin, Sao Paulo State, are included in Sao Bento Group, by correlation with the Piramboia, Botucatu and Serra Geral formations. The Botucatu Formation's age is bracketed between the Upper Jurassic and the Lower Cretaceous (Neocomian). The Botucatu Formation is composed of aeolian sandstones showing cross-stratification from medium to large scale, a typical trait of migrating dunes. Ichnofossils were collected in the Sao Bento Quarry, located in the city of Araraquara, Sao Paulo State. Samples MPA-002 e MPA-003, respectively, are the negative epirelief and positive hyporelief of the same trace fossil. MPA-001 is a negative epirelief. These features show a removal of sedimentary material, in contrast to the morphology of ornithopod and theropod dinosaur tracks, where compression and deformation of unconsolidated sedimentary layers occurs. These trace fossils show a pattern corresponding to erosion caused by evacuation of liquid wastes and are classificated as urolites, because this term has already been applied to the occurrence of ichnofossils of this type in France and Germany. The morphostructure of these urolites is very similar to the erosional geometry produced in the substrate by expelled liquid waste of modern ratite birds, such as _Struthio camelus_ (ostrich). These urolites are the first records in Brazil of this type of ichnofossil, and is also one of the first examples of trace fossils attributed to liquid waste expulsion by dinosaurs."