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Scaling bite force in predatory animals


Scaling of bite force with body size in extant predators is investigated to extrapolate expected values in large predators, such as theropod dinosaurs. A regression analysis of bite force to body mass was performed in extant predators and was observed to scale similarly to area with volume in isometric bodies. Bite force in theropods can be expected to scale along this geometric similarity. Forces predicted in this way are significantly higher than previous estimates but are still disproportionately low for the colossal sizes attained by theropods. It is shown that muscle-driven bite force is progressively weaker relative to increase in body mass. Bite force need not increase in proportion to body size, as larger animals would need less effort to bite through resistant materials: material properties of soft tissue vary little among vertebrates and bone can be crushed with forces already exerted by extant predators. Therefore, bite force may not need to be maximised.



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Scaling bite force in predatory animals
Estimating PCSA in theropod dinosaurs
Phylogeny of theropods

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Manabu Sakamoto
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