Abstract

The study of dinosaur paleopathology has enriched our understanding of their living conditions and their intra- and interspecific behavior. In this study, I examined lesions on bones from a monospecific bone bed (Edmontosaurus annectens) and their implications for E. annectens behavior and the ecological conditions that affected this population. The bone bed contains abundant, mostly well-preserved, scattered, and disarticulated bones, mostly representing an adult population of E. annectens. From the 3013 bones examined, 96 bones displayed genuine pathologies such as: hypertrophic ossification, healed fractures, tooth traces, idiopathic or traumatic shaft angulation, bone fusion, degenerative joint diseases, osteochondrosis, infection, neoplasm, and idiopathic bone stenosis. Etiologies were attributable to trauma, infection, neoplasm, and developmental and idiopathic lesions. Tail trauma, mostly in caudal vertebrae, and developmental joint diseases in pedal phalanges comprised the majority of the paleopathological manifestations, representing respectively 69% and 17% of all pathological cases. Frequent pre-mortem traumatic lesions in middle-distal caudal vertebrae of E. annectens suggest tail anatomy, biomechanics and associated tail usage. Other manifestations of trauma such as degenerative joint diseases in distal caudal centra also indicate mechanical stress in that respective tail region. Caudal lesions suggest that E. annectens frequently used and injured its tail. Additional joint lesions associated with developmental etiologies such as osteochondrosis, are repeatedly manifested in pedal phalanges suggesting a developmental predisposition to joint disease in E. annectens. Most manifestations of tooth traces in the E. annectens bones are peri- or post-mortem. The density of striations and serrations characterizing these traces indicate Tyrannosaurus rex teeth, suggesting successful predation or scavenging of this E. annectens population. Other bone lesions suggest pseudopathologies that resulted from biogenic and diagenetic taphonomic factors. My findings, in combination with current reports of hadrosaurian pathologies, indicate common manifestations of diseases amongst hadrosaurs, and specific to this study, the morbidities that frequently affected the E. annectens population. In this study I (1) add to the literature of dinosaur paleopathology, especially that of hadrosaurs; (2) validate paleopathological usefulness in interpretations pertaining to animal behavior, biomechanics, and living conditions; and (3) other suggestions for further research.

LLU Discipline

Biology

Department

Biology

School

School of Medicine

First Advisor

Leonard Brand

Second Advisor

Arthur V. Chadwick

Third Advisor

William K. Hayes

Fourth Advisor

Kevin E. Nick

Fifth Advisor

Suzanne Phillips

Sixth Advisor

Elizabeth Rega

Degree Name

Doctor of Philosophy (PhD)

Degree Level

Ph.D.

Year Degree Awarded

2019

Date (Title Page)

6-2019

Language

English

Library of Congress/MESH Subject Headings

Paleopathology; Hadrosauridae; Wyoming

Type

Dissertation

Page Count

xviii, 211 p.

Digital Format

PDF

Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Collection

Loma Linda University Electronic Theses and Dissertations

Collection Website

http://scholarsrepository.llu.edu/etd/

Repository

Loma Linda University. Del E. Webb Memorial Library. University Archives

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Paleobiology Commons

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