This study reports on the three-dimensional spatial arrangement and movements of the skeleton of Anhanguera santanae (Pterodactyloidea: Ornithocheiridae), determined using exceptionally well-preserved uncrushed fossil material, and a rigid-body method for analysing the joints of extinct animals. The geometric results of this analysis suggest that the ornithocheirids were inherently unstable in pitch and yaw. As a result, pitch control would
probably have been brought about by direct adjustment of the angle of attack of the wing, by raising or lowering the trailing edge from the root using the legs if, as is indicated in soft-tissue specimens of a number of unrelated pterosaur species, the ... Read more »

The analysis of some morphological characteristics of protoceratopoid skeletons, the extent of mobility of the vertebral column, and the probable adaptive significance of these features suggest that Bagaceratops had a mostly aquatic mode of life, Protoceratops was semiaquatic, Udanoceratops was facultatively aquatic, and Leptoceratops was predominantly terrestrial. Protoceratopoids were quadrupeds, with the prevalence of hind limbs, probably using slow or rapid trotlike gait. An asymmetrical locomotion was most likely impossible. On dry land, Bagaceratops and Protoceratops moved slowly. Udanoceratops and Leptoceratops
approximately equally used rapid and slow locomotor modes, although the ... Read more »

An exceptionally preserved subadult specimen (JRF 115H) of a hadrosaurid, Brachylophosaurus canadensis, from the Judith River Formation near Malta, Montana, contains abundant plant fragments concentrated within the body cavity. We examined the taphonomy of the carcass and analyzed the gut-region material to test whether the organic remains represent fossilized gut contents. The dinosaur was buried in a fluvial channel setting, and the excellent articulation, integument impressions, and lack of scavenging indicate rapid burial. The organic material occupies a volume of at least 5750 cm3, and
comparable material is not found outside the carcass. The carcass contents include 63% clay, 16% ... Read more »