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Updated: Jun 19, 2026
08:46
Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field
Published on: August 2, 2011
Common avian infection plagued the tyrant dinosaurs
Ewan D S Wolff1, Steven W Salisbury, John R Horner
1Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, Wisconsin, United States of America. ewolff@wisc.edu
Plos One
|October 1, 2009
Summary
Fossilized tyrannosaurid jaw lesions, previously thought to be infections or bite wounds, are now identified as an avian parasitic disease called trichomonosis. This finding reveals an ancient origin for this disease in non-avian dinosaurs, likely spread through behavior and diet.
Area of Science:
- Paleontology
- Paleopathology
- Paleobiology
Background:
- Tyrannosaurid fossils frequently exhibit erosive mandibular lesions.
- Previous hypotheses attributed these lesions to bacterial infections or intraspecific combat.
Purpose of the Study:
- To investigate the etiology of erosive lesions found on tyrannosaurid mandibles.
- To determine if these lesions represent a known disease with an ancient evolutionary origin.
Main Methods:
- Conducted an extensive survey of tyrannosaurid specimens with mandibular lesions.
- Described, measured, and photographed lesions for comparative analysis.
- Surveyed related archosaurs for similar pathological indicators.
Main Results:
- Identified ten tyrannosaurid individuals with characteristic full-thickness erosive lesions.
- Lesion morphology is consistent with trichomonosis, an avian parasitic infection.
- Similar lesions were not found in surveyed related archosaurs.
Conclusions:
- The study provides the first evidence of an avian transmissible disease in non-avian theropod dinosaurs.
- Tyrannosaurid lesions are attributed to trichomonosis, caused by a Trichomonas gallinae-like protozoan.
- The disease likely spread through intraspecific behavior, prey, or cannibalism, potentially leading to mortality via starvation.
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