Sauropodomorpha represents an important group of Mesozoic megaherbivores, and includes the largest terrestrial animals ever known. It was the first dinosaur group to become abundant and widespread, and its members formed a significant component of terrestrial ecosystems from the Late Triassic until the end of the Cretaceous. Both of these factors have been explained by their adoption of herbivory, but understanding the evolution of sauropodomorph feeding has been hampered by the scarcity of biomechanical studies. To address this, the jaw adductor musculature of the basal sauropodomorph Plateosaurus and the sauropod Camarasaurus have been reconstructed. These reconstructions provide boundary conditions for finite element models to assess differences in structural performance between the two taxa. Results demonstrate that Camarasaurus was capable of much greater bite forces than Plateosaurus, due to greater relative adductor muscle mass and shape changes to the mandible. The skull and mandible of Camarasaurus are also ‘stronger’ under static biting. The Plateosaurus mandible appears to compromise structural efficiency and force transmission in order to maintain relatively high jaw closure speed. This supports suggestions of facultative omnivory in basal sauropodomorph taxa. The expanded mandibular symphysis and ‘lateral plates’ of sauropods each lead to greater overall craniomandibular robustness, and may have been especially important in accommodating forces related to asymmetric loading. The functional roles of these characters, and observed general shape changes in increasing skull robustness, are consistent with hypotheses linking bulk-herbivory with the origin of Sauropoda and the evolution of gigantism.,Supporting InformationSupporting information for "Comparative cranial myology and biomechanics of Plateosaurus and Camarasaurus and evolution of the sauropod feeding apparatus". Includes additional details and views of the osteological and myological virtual reconstructions and additional finite-element modelling results.Plateosaurus cranium modelModel of the cranium of Plateosaurus produced for this study.platskull.stlPlateosaurus mandible modelModel of the mandible of Plateosaurus produced for this studyplatmand.stlCamarasaurus skull modelModel of the skull of Camarasaurus produced for this studycamskull.stlCamarasaurus mandible modelModel of the mandible of Camarasaurus produced for this studycammand.stlPlateosaurus anterior biteAbaqus input file of the finite element model of the cranium of Plateosaurus, simulating a bilateral bite at the 4 anteriormost teeth.plateosaurus_ant4.inpPlateosaurus middle biteAbaqus input file of the finite element model of the cranium of Plateosaurus, simulating a bilateral bite at the 4 middle teeth.plateosaurus_mid4.inpPlateosaurus posterior biteAbaqus input file of the finite element model of the cranium of Plateosaurus, loaded to replicate a static bite at the posteriormost four teeth.plateosaurus_post4.inpPlateosaurus dentineAbaqus input file of a finite element model of the cranium of Plateosaurus, with the material properties of dentine assigned to the teeth. This was used in the sensitivity analyses testing the influence of tooth material properties on observed results.plateosaurus_dentine.inpPlateosaurus enamelAbaqus input file of a finite element model of the cranium of Plateosaurus, with the material properties of enamel assigned to the teeth. This formed part of the sensitivity analyses testing the influence of tooth material properties on results.plateosaurus_enamel.inpPlateosaurus mandible anterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating a bilateral bite at the anteriormost four teeth.plateosaurus_mandible_ant4.inpPlateosaurus mandible middle biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating a bilateral bite at the middle four teeth.plateosaurus_mandible_mid4.inpPlateosaurus mandible posterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating a bilateral bite at the posterior four teeth.plateosaurus_mandible_post4.inpPlateosaurus mandible dentineAbaqus input file of a finite element model of the mandible of Plateosaurus, with the material properties of dentine assigned to the teeth. This formed part of the sensitivity analyses testing the influence of the material properties of teeth on the results.plateosaurus_mandible_dentine.inpPlateosaurus mandible enamelAbaqus input file of a finite element model of the mandible of Plateosaurus, with the material properties of enamel assigned to the teeth. This formed part of the sensitivity analyses testing the influence of material properties of the teeth on results.plateosaurus_mandible_enamel.inpPlateosaurus mandible unilateral anterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating an unilateral bite at the anterior biting position.plat_mand_unilateral_ant.inpPlateosaurus mandible unilateral middle biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating a unilateral bite at the middle biting position.plat_mand_unilateral_mid.inpPlateosaurus mandible unilateral posterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating an unilateral bite at the posterior biting position.plat_mand_unilateral_post.inpPlateosaurus scaled anterior biteAbaqus input file of a finite element model of the cranium of Plateosaurus, simulating a bite at the anteriormost four teeth. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_scaled_ant4.inpPlateosaurus scaled middle biteAbaqus input file of a finite element model of the cranium of Plateosaurus, simulating a bite at the middle four teeth. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_scaled_mid4.inpPlateosaurus scaled posterior biteAbaqus input file of a finite element model of the cranium of Plateosaurus, simulating a bite at the posteriormost four teeth. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_scaled_post4.inpPlateosaurus mandible scaled anterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating a bite at the anteriormost four teeth. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_mandible_scaled_ant4.inpPlateosaurus mandible scaled middle biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating a bite at the middle four teeth. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_mandible_scaled_mid4.inpPlateosaurus mandible scaled posterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating a bite at the posteriormost four teeth. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_mandible_scaled_post4.inpPlateosaurus mandible scaled unilateral anterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating an unilateral bite at the anterior biting position. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_mandible_scaled_unilateral_ant4.inpPlateosaurus mandible scaled unilateral middle biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating an unilateral bite at the middle biting position. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_mandible_scaled_unilateral_mid4.inpPlateosaurus mandible scaled unilateral posterior biteAbaqus input file of a finite element model of the mandible of Plateosaurus, simulating an unilateral bite at the posterior biting position. Muscle forces have been scaled so that the total applied force/surface area equals that of Camarasaurus (the "structural comparison").plateosaurus_mandible_scaled_unilateral_post4.inpCamarasaurus anterior biteAbaqus input file of a finite element model of the cranium of Camarasaurus, simulating a bite at the anteriormost four teeth.camarasaurus_ant4.inpCamarasaurus middle biteAbaqus input file of a finite element model of the cranium of Camarasaurus, simulating a bite at the middle four teeth.camarasaurus_mid4.inpCamarasaurus posterior biteAbaqus input file of a finite element model of the cranium of Camarasaurus, simulating a bite at the posteriormost four teeth.camarasaurus_post4.inpCamarasaurus dentineAbaqus input file of a finite element model of the cranium of Camarasaurus, with the material properties of dentine assigned to the teeth. This formed part of the sensitivity analyses testing the significance of the material properties of the teeth on results.camarasaurus_dentine.inpCamarasaurus enamelAbaqus input file of a finite element model of the cranium of Camarasaurus, with the material properties of enamel assigned to the teeth. This formed part of the sensitivity analyses testing the significance of the material properties of the teeth on results.camarasaurus_enamel.inpCamarasaurus mandible anterior biteAbaqus input file of a finite element model of the mandible of Camarasaurus, simulating a bilateral bite at the anteriormost four teeth.camarasaurus_mandible_ant4.inpCamarasaurus mandible middle biteAbaqus input file of a finite element model of the mandible of Camarasaurus, simulating a bilateral bite at the middle four teeth.camarasaurus_mandible_mid4.inpCamarasaurus mandible posterior biteAbaqus input file of a finite element model of the mandible of Camarasaurus, simulating a bilateral bite at the posteriormost four teeth.camarasaurus_mandible_post4.inpCamarasaurus mandible dentineAbaqus input file of a finite element model of the mandible of Camarasaurus, with the material properties of dentine assigned to the teeth. This formed part of the sensitivity analyses testing the influence of the material properties of the teeth on results.camarasaurus_mandible_dentine.inpCamarasaurus mandible enamelAbaqus input file of a finite element model of the mandible of Camarasaurus, with the material properties of enamel assigned to the teeth. This formed part of the sensitivity analyses testing the influence of the material properties of the teeth on results.camarasaurus_mandible_enamel.inpCamarasaurus mandible unilateral anterior biteAbaqus input file of a finite-element model of the mandible of Camarasaurus, simulating an unilateral bite at the posterior biting position.camarasaurus_mandible_unilateral_ant4.inpCamarasaurus mandible unilateral middle biteAbaqus input file of a finite-element model of the mandible of Camarasaurus, simulating an unilateral bite at the middle biting position.camarasaurus_mandible_unilateral_mid.inpCamarasaurus mandible unilateral posterior biteAbaqus input file of a finite-element model of the mandible of Camarasaurus, simulating an unilateral bite at the posterior biting position.camarasaurus_mandible_unilateral_post.inp,
Date made available | 16 Sept 2017 |
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Publisher | Dryad |
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