title: A 'terror of tyrannosaurs': the first trackways of tyrannosaurids and evidence of gregariousness and pathology in Tyrannosauridae.
abstract: The skeletal record of tyrannosaurids is well-documented, whereas their footprint record is surprisingly sparse. There are only a few isolated footprints attributed to tyrannosaurids and, hitherto, no reported trackways. We report the world's first trackways attributable to tyrannosaurids, and describe a new ichnotaxon attributable to tyrannosaurids. These trackways are from the Upper Cretaceous (Campanian - Maastrichtian) of northeastern British Columbia, Canada. One trackway consists of three tridactyl footprints, and two adjacent trackways consist of two footprints each. All three trackways show animals bearing southeast within an 8.5 meter-wide corridor. Similarities in depth and preservation of the tyrannosaurid tracks indicate that these three trackways were made by track-makers walking concurrently in the same direction. These trackways add significantly to previous osteology-based hypotheses of locomotion and behavior in Tyrannosauridae by providing ichnologic support for gregariousness in tyrannosaurids, and the first record of the walking gait of tyrannosaurids.
authors: Peace Region Palaeontology Research Centre, Tumbler Ridge, British Columbia, Canada; Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors: Richard T
authors: RT
authors: McCrea
authors: Peace Region Palaeontology Research Centre, Tumbler Ridge, British Columbia, Canada; Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors: Lisa G
authors: LG
authors: Buckley
authors: Department of Geosciences, Indiana-Purdue University, Fort Wayne, Indiana, United States of America.
authors: James O
authors: JO
authors: Farlow
authors: Dinosaur Trackers Research Group, University of Colorado at Denver, Denver, Colorado, United States of America.
authors: Martin G
authors: MG
authors: Lockley
authors: Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors: Philip J
authors: PJ
authors: Currie
authors: Bureau of Land Management, Denver, Colorado, United States of America.
authors: Neffra A
authors: NA
authors: Matthews
authors: Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors: S George
authors: SG
authors: Pemberton
mesh_terms: D000818:Animals; D001955:British Columbia; D025061:Dinosaurs / Q000033:anatomy & histology* / Q000145:classification; D005580:Fossils; D008124:Locomotion; D010163:Paleontology