Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/935911
- Title
- Devourer of Gods: the palaeoecology of the Cretaceous pliosaur Kronosaurus queenslandicus
- Author/Creator
-
McHenry, Colin Richard
- Institution
- University of Newcastle. Faculty of Science & Information Technology, School of Environmental and Life Sciences
- Description
- Research Doctorate - Doctor of Philosophy (PhD)
- Description
- The large pliosaur Kronosaurus queenslandicus is known from numerous specimens from the Early Cretaceous marine sediments of the Australian Great Artesian Basin. The preservation of these specimens in nodular limestone generally lacks pronounced taphonomic distortion, allowing the three-dimensional shape of the osteology, in particular the skull, to be inferred with confidence. Three-dimensional geometry is critical data for the functional analyses that can form the basis for reconstruction of palaeoecology, in particular, approaches based in computational biomechanics that make use of high resolution Finite Element Modelling. These techniques have been used successfully to infer diet and feeding behaviour in various species of extinct carnivore, and are here applied to a species of large pliosaur for the first time. The cranial anatomy of Kronosaurus queenslandicus is here summarised for the first time, and outstanding questions concerning the taxonomy of the relevant material are addressed as fully as possible given available data. Overall body proportions and size are estimated in the context of other known material from specimens of large pliosaurs. The material examined supports the hypothesis that there is one species of large pliosaur in the Late Albian the Great Artesian Basin, and this material is referred to Kronosaurus queenslandicus Longman 1924. Material from the Late Aptian of the Great Artesian Basin is also Kronosaurus, and is presently referred to Kronosaurus queenslandicus Longman 1924: however questions about the anatomy of Kronosaurus boyacensis Hampe 1992 mean that further examination of material to hand, or recovery of new specimens from the Late Aptian, may require the taxonomic status of the Late Aptian material to be reviewed. Kronosaurus is a member of the Brachaucheniidae Williston 1925. Maximum size is 10.5 metres total length and approximately ~11,000 kg body mass. Biomechanical analysis of the skull of Kronosaurus shows that it had a high bite force, comparable to that predicted for a hypothetical similar sized saltwater crocodile Crocodylus porosus. The magnitude of its maximum bite force, around 30,000 Newtons, was likely exceeded by Tyrannosaurus rex and Carcharocles megalodon. Finite element modelling of the skull, compared with the skull of a 3.1 metre Crocodylus porosus, suggests that the skull of Kronosaurus carried more strain under loads simulating feeding on large prey. Accordingly, maximum prey size, relative to predator body size, is interpreted as lower in Kronosaurus than for a 3.1 metre C. porosus, although the magnitude of this limit is unknown due to incomplete data on the feeding ecology of C. porosus. Other evidence, from functional morphology, taphonomy, and comparison with extant aquatic carnivores suggests that Kronosaurus was the apex predator of the Australian Early Cretaceous inland seas. Relatively small prey were likely to be an important component of the diet of Kronosaurus, although certain morphological features of the skull appear to have permitted predation upon larger prey when available. Several of these morphological features may constitute evolutionary adaptations to the conflicting mechanical demands of feeding on small and large prey.
- Relation
- University of Newcastle Research Higher Degree Thesis
- Date
- 2009
- Keyword(s)
-
palaeoecology;
paleoecology;
Plesiosauria;
Sauropterygia;
Cretaceous;
Australia;
Great Artesian Basin;
pliosaur;
plesiosaur;
biomechanics;
vertebrate palaeontology;
vertebrate paleontology;
Finite Element Analysis;
Kronosaurus;
Brachaucheniidae
- Resource Type
- thesis
- Rights
- Copyright 2009 Colin Richard McHenry
- Identifier
- http://hdl.handle.net/1959.13/935911
- Language
- eng
-
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