Thursday, June 02, 2005

Dr. Jørn Hurum: Monsterforskeren

… er én av omtrent 100 dinosaureksperter i verden. Han er førsteamanuensis ved Paleontologisk museum, Naturhistoriske museer og Botanisk hage ved Universitetet i Oslo, og dukker dessuten stadig opp i populærvitenskapelige programmer på TV og radio.

Hurum har vært mange steder i verden for å spa opp spennende dinosaurbein, men er for tida kanskje aller mest interessert i Svalbard. Der har han funnet fotsporene til en diger dinosaur, og håpet er nok en dag å snuble over skjelettet.
If you can read Norwegian you than you can read this interview with the palaeoblogger’s favourite Norwegian vertebrate palaeontologist, Jørn Hurum. I’m not sure what they’ve talking about but if it includes a discussion of Metallica, the history of geology, Pink Floyd and theropod dinosaurs, than I’m sure it’s all about Jørn’s favourite things in life.

Here are a couple of recent papers by Jørn for you to check out:

Giant theropod dinosaurs from Asia and North America: Skulls of Tarbosaurus bataar and Tyrannosaurus rex compared. 2003. Jørn H. Hurum and Karol Sabath. Acta Palaeontologica Polonica 48(2): 161-190.
The skull of a newly prepared Tarbosaurus bataar is described bone by bone and compared with a disarticulated skull of Tyrannosaurus rex. Both Tarbosaurus bataar and Tyrannosaurus rex skulls are deep in lateral view. In dorsal view, the skull of T. rex is extremely broad posteriorly but narrows towards the snout; in Ta. bataar the skull is narrower (especially in its ventral part: the premaxilla, maxilla, jugal, and the quadrate complex), and the expansion of the posterior half of the skull is less abrupt. The slender snout of Ta. bataar is reminiscent of more primitive North American tyrannosaurids. The most obvious difference between T. rex and Ta. bataar is the doming of the nasal in Ta. bataar which is high between the lacrimals and is less attached to the other bones of the skull, than in most tyrannosaurids. This is because of a shift in the handling of the crushing bite in Ta. bataar. We propose a paleogeographically based division of the Tyrannosaurinae into the Asiatic forms (Tarbosaurus and possibly Alioramus) and North American forms (Daspletosaurus and Tyrannosaurus). The division is supported by differences in anatomy of the two groups: in Asiatic forms the nasal is excluded from the major series of bones participating in deflecting the impact in the upper jaw and the dentary-angular interlocking makes a more rigid lower jaw.

Skull structure and evolution in tyrannosaurid dinosaurs. 2003. Philip J. Currie, Jørn H. Hurum, and Karol Sabath. Acta Palaeontologica Polonica 48(2): 227-234.
Tyrannosauridae can be subdivided into two distinct subfamilies: the Albertosaurinae and the Tyrannosaurinae. Previously recognized subdivisions Aublysodontinae and Shanshanosaurinae are rejected because they are based on insufficient material and juvenile specimens. Our results are based upon a phylogenetic analysis using PAUP program (Swofford 1999) of 77 skull characters and seven genera (Albertosaurus, Alioramus, Daspletosaurus, Gorgosaurus, Nanotyrannus, Tarbosaurus, and Tyrannosaurus); with Allosaurus as outgroup. Of the 77 characters used, more than half were parsimony informative. A single most parsimonious tree was obtained with the Tree Length being 88. The analysis of cranial characters and comparison of postcranial features reveal that Tarbosaurus bataar is not the sister taxon of Tyrannosaurus rex (contra Holtz 2001). Their similarities are partially due to the fact that both are extremely large animals. Thus,Tarbosaurus should be considered a genus distinct from Tyrannosaurus.
Photos from HERE and HERE.