Head-biting behavior in theropod dinosaurs: paleopathological evidence /

Source: OAI

ABSTRACT Cranial material of Sinraptor dongi (Upper Jurassic, Xinjiang, China), Gorgosau- rus libratus, Daspletosaurus torosus (Upper Cretaceous, Alberta, Canada), and other large theropod dinosaurs exhibit similar paleopathological anomalies indicative of aggressive in- tra- or interspecific biting. Tooth strike trauma includes osseous lesions caused by solitary or multiple tooth punctures, or by dragging or gouging the tooth tips across the surfaces of cranial elements. Many of these lesions were undergoing active healing at the time of death. One isolated tyrannosaurid dentary bears a broken off and embedded tooth tip of another ty- rannosaur. Comparison with unhealed large theropod toothmarks on prey bone suggests that sublethal wounds of these types were caused by other large theropods, possibly rival conspecifics. This may indicate aggressive head or face-biting behavior in certain theropod families. Other associated traumatic osteopathy typified as localized rib and fibula fractures were observed but cannot be directly correlated with violent intra- or interspecific behavior. Healed and healing bite wounds of the head may be related to a number of factors. Establish- ment of dominance within a pack and territorial behavior are considered as two of the most likely causes. Study of paleopathologies is demonstrated to be a useful tool for understand- ing dinosaur behavior.

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    ABSTRACT: BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. BioOne ( is a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne's Terms of Use, available at Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder. ABSTRACT—Bioerosion trace fossils in bones are defined as biogenic structures that cut or destroy hard bone tissue as the result of mechanical and/or chemical processes. Under the premise that their paleoecological potential can completely be realized only through correct taxonomic assignment, this work focuses on the methodology for naming these biogenic structures. Thus, we propose the following ichnotaxobases in order to assist in naming trace fossils in bones: general morphology, bioglyphs, filling, branching, pattern of occurrence, and site of emplacement. The most common general morphologies are: pits and holes (borings); chambers; trails; tubes; channels (canals); grooves; striae; and furrows. The main types of bioglyphs are grooves and scratches, which may display different arrangements, such as parallel and opposing, or arcuate paired. The nature of the fill may help recognition of the origin, composition, and relationship with the surrounding sediment, as well as processes of destruction or consumption of bony tissue. The structure and layout of the filling, such as meniscate backfill or pelleted filling, offer information about the bioeroding processes. Branching structures on cortical bone are present in canals and furrows. Where the trace penetrates spongy bone, branching structures are forming tunnels that may connect internal chambers. The common patterns of occurrence are individual, paired, grouped, overlapping, lined, and arcuate. The site of emplacement may be in cortical bone, spongy bone, articular surfaces, internal bone microstructures, and external bone anatomical structures. The use of substrate as an ichnotaxobase is problematic, but as biological substrate, bone itself is a valuable source of information for paleoecologic and ethologic inferences. Given the paleontological importance of bioerosion trace fossils in bones, we underscore interactions between ichnology and other sciences, such as forensic entomology, archaeology, paleoecology, and taphonomy.
    Journal of Paleontology 01/2014; 88(1):195-203. DOI:10.1666/11-058 · 1.20 Impact Factor
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    ABSTRACT: Bone pathology in the titanosaur dinosaur Uberabatitan ribeiroi from the Mar�ılia Formation (Bauru Group, Late Cretaceous) of Uberaba city (Minas Gerais State, Brazil) is analysed here. They include two fused procoelous mid-caudal vertebrae (CPPLIP-1020) and a haemal arch (CPPLIP-1006) of the middle section of the tail with a healing fracture callus. The analyses of the caudal vertebrae CPPLIP-1020 of Uberabatitan permit us to recognize the following signs, based on CT scan and external macroscopic observations: (1) ossified longitudinal tendons; (2) likely ossified intervertebral disc, producing fused vertebral bodies; (3) fused right zygapophyseal process with a laterally developed osteophyte affecting this joint; (4) osteophytes and exostoses at different portions of the vertebrae; (5) cloacae, bone erosion and likely internal infection. According to all the processes observed in these caudals, we could not discard at least two possibilities for the diagnosis of the fused vertebrae. It could be the result of a spondyloarthropathy process (considering most of the observed signs) or possibly have been associated with an infection (e.g. discospondylitis/infections spondylitis or septic arthritis). The bone lesion record in Uberabatitan ribeiroi from the Late Cretaceous of Brazil increases the range of study of titanosaur dinosaurs, which although have a large fossil record, have few pathological studies.
    Lethaia 12/2014; DOI:10.1111/let.12117 · 2.19 Impact Factor
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