Comparative cranial biomechanics reveal that Late Cretaceous tyrannosaurids exerted relatively greater bite force than in early-diverging tyrannosauroids.

Autor: Johnson-Ransom E; Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, USA., Li F; Tianjin Natural History Museum, Tianjin, China., Xu X; Centre for Vertebrate Evolutionary Biology, Yunnan University, Kunming, China.; Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China., Ramos R; Illustration Department, Rocky Mountain College of Art and Design, Lakewood, Colorado, USA., Midzuk AJ; Evolutionary Studies Institute, School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa., Thon U; Informatik Department, Mannheim University of Applied Sciences, Mannheim, Germany., Atkins-Weltman K; College of Osteopathic Medicine, Oklahoma State University, Tulsa, Oklahoma, USA., Snively E; Oklahoma State University College of Osteopathic Medicine-Cherokee Nation, Tahlequah, Oklahoma, USA.
Jazyk: angličtina
Zdroj: Anatomical record (Hoboken, N.J. : 2007) [Anat Rec (Hoboken)] 2024 May; Vol. 307 (5), pp. 1897-1917. Date of Electronic Publication: 2023 Sep 29.
DOI: 10.1002/ar.25326
Abstrakt: Tyrannosaurus has been an exemplar organism in feeding biomechanical analyses. An adult Tyrannosaurus could exert a bone-splintering bite force, through expanded jaw muscles and a robust skull and teeth. While feeding function of adult Tyrannosaurus has been thoroughly studied, such analyses have yet to expand to other tyrannosauroids, especially early-diverging tyrannosauroids (Dilong, Proceratosaurus, and Yutyrannus). In our analysis, we broadly assessed the cranial and feeding performance of tyrannosauroids at varying body sizes. Our sample size included small (Proceratosaurus and Dilong), medium-sized (Teratophoneus), and large (Tarbosaurus, Daspletosaurus, Gorgosaurus, and Yutyrannus) tyrannosauroids, and incorporation of tyrannosaurines at different ontogenetic stages (small juvenile Tarbosaurus, Raptorex, and mid-sized juvenile Tyrannosaurus). We used jaw muscle force calculations and finite element analysis to comprehend the cranial performance of our tyrannosauroids. Scaled subtemporal fenestrae areas and calculated jaw muscle forces show that broad-skulled tyrannosaurines (Tyrannosaurus, Daspletosaurus, juvenile Tyrannosaurus, and Raptorex) exhibited higher jaw muscle forces than other similarly sized tyrannosauroids (Gorgosaurus, Yutyrannus, and Proceratosaurus). The large proceratosaurid Yutyrannus exhibited lower cranial stress than most adult tyrannosaurids. This suggests that cranial structural adaptations of large tyrannosaurids maintained adequate safety factors at greater bite force, but their robust crania did not notably decrease bone stress. Similarly, juvenile tyrannosaurines experienced greater cranial stress than similarly-sized earlier tyrannosauroids, consistent with greater adductor muscle forces in the juveniles, and with crania no more robust than in their small adult predecessors. As adult tyrannosauroid body size increased, so too did relative jaw muscle forces manifested even in juveniles of giant adults.
(© 2023 The Authors. The Anatomical Record published by Wiley Periodicals LLC on behalf of American Association for Anatomy.)
Databáze: MEDLINE
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