Skull of a Jurassic ankylosaur (Dinosauria)
Article Abstract:
A skull of a Late Jurassic ankylosaur collected from the Upper Jurassic Morrison Formation of Wyoming has seven premaxillary teeth, thus distinguishing it from all other ankylosaurids. The specimen, designated Gargoyleosaurus parkpini gen. et sp. nov., has a mixture of characters seen in the later Cretaceous families of ankylosaurs, the Nodosauridae and Ankylosauridae. The scooped beak formed by the premaxillary bones is long and narrow, similar to that seen in Cretaceous nodosaurids. This discovery indicates that ankylosaur evolution was well advanced by the Late Jurassic period.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
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A new missing link
Article Abstract:
A recently discovered non-avian theropod dinosaur may be the missing link between small carnivorous dinosaurs known as theropods and birds. This dinosaur, which researchers have named Unenlagia comaheunsis, dates from the early Late Cretaceous, and was discovered in Patagonia, Argentina. It seems to have an even mixture of the features of primitive coelurosaurs, a type of theropod, and those of birds. Researchers believe that Unenlagia was a descendant of a lineage which diverged shortly before the fully feathered and flying line which leads to true birds.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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A Velociraptor wishbone
Article Abstract:
The discovery of a furcula in Dromaeosauridae, a dinosaur group believed to be the closest relative of birds, provides new material in the debate about the links between dinosaurs and birds. The furcula was identified in a partial skeleton of Velociraptor mongoliensis found at Tugrugeen Shireh, Mongolia, in 1991. The furcula is an articulation between the scapulocoracoids anterior to the sternal plates. It is located in the same place as in oviraptorids and birds.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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