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Fostowicz-Frelik Ł, Cox PG, Li Q. Mandibular characteristics of early Glires (Mammalia) reveal mixed rodent and lagomorph morphotypes. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220087. [PMID: 37183896 PMCID: PMC10184241 DOI: 10.1098/rstb.2022.0087] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 02/16/2023] [Indexed: 05/16/2023] Open
Abstract
Glires (rodents, lagomorphs and their fossil kin) is the most speciose and arguably most diversified clade of living placentals. Different lineages within the Glires evolved basically opposite chewing movements: a mostly transversal power stroke in lagomorphs, and a mostly proal power stroke in rodents, but the ancestral condition for Glires is still unclear. To address this knowledge gap, we studied the mandibles of Chinese Palaeocene Glires representing the duplicidentate (lagomorph-like; Mimotona) and simplicidentate (rodent-like; Eomylus and Heomys) lineages. To assess the mechanical resistance of mandibles to bending and torsion, we calculated the section modulus. The dentaries differ greatly in morphology and the region where the maximum grinding force was likely applied. The early Palaeocene Mimotona lii and the middle Palaeocene Mimotona robusta and Heomys orientalis all show a pattern of increasing strength moving posteriorly along the mandible, similar to sciurids and the mountain beaver. By contrast, the late Palaeocene Eomylus sp. mandible was strongest in the m1 region, a pattern seen in lagomorphs and the stem placental Zofialestes. Our results indicate the early diversification of mandible structure of Glires, demonstrate a mixture of duplicidentate and simplicidentate characters among the basal Glires and suggest an early occurrence of a lagomorph-like morphotype. This article is part of the theme issue 'The mammalian skull: development, structure and function'.
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Affiliation(s)
- Łucja Fostowicz-Frelik
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
- Institute of Paleobiology, Polish Academy of Sciences, 00-818 Warsaw, Poland
| | - Philip G. Cox
- Centre for Integrative Anatomy, Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Qian Li
- Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China
- Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Beijing 100044, People's Republic of China
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2
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Cox PG, Watson PJ. Masticatory biomechanics of red and grey squirrels ( Sciurus vulgaris and Sciurus carolinensis) modelled with multibody dynamics analysis. ROYAL SOCIETY OPEN SCIENCE 2023; 10:220587. [PMID: 36816846 PMCID: PMC9929510 DOI: 10.1098/rsos.220587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
The process of feeding in mammals is achieved by moving the mandible relative to the cranium to bring the teeth into and out of occlusion. This process is especially complex in rodents which have a highly specialized configuration of jaw adductor muscles. Here, we used the computational technique of multi-body dynamics analysis (MDA) to model feeding in the red (Sciurus vulgaris) and grey squirrel (Sciurus carolinensis) and determine the relative contribution of each jaw-closing muscle in the generation of bite forces. The MDA model simulated incisor biting at different gapes. A series of 'virtual ablation experiments' were performed at each gape, whereby the activation of each bilateral pair of muscles was set to zero. The maximum bite force was found to increase at wider gapes. As predicted, the superficial and anterior deep masseter were the largest contributors to bite force, but the temporalis had only a small contribution. Further analysis indicated that the temporalis may play a more important role in jaw stabilization than in the generation of bite force. This study demonstrated the ability of MDA to elucidate details of red and grey squirrel feeding biomechanics providing a complement to data gathered via in vivo experimentation.
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Affiliation(s)
- Philip G. Cox
- Department of Cell and Developmental Biology, University College London, London, UK
- Department of Archaeology, University of York, York, UK
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3
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Segura V, Flores D, Jayat P, Martin G. Evolutionary patterns of cranial ontogeny in Sigmodontines (Rodentia, Cricetidae). J ZOOL SYST EVOL RES 2021. [DOI: 10.1111/jzs.12530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Valentina Segura
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
- Unidad Ejecutora Lillo Consejo Nacional de Investigaciones Científicas y Técnicas–Fundación Miguel Lillo San Miguel de Tucumán Argentina
| | - David Flores
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
- Unidad Ejecutora Lillo Consejo Nacional de Investigaciones Científicas y Técnicas–Fundación Miguel Lillo San Miguel de Tucumán Argentina
- Instituto de Vertebrados Fundación Miguel Lillo San Miguel de Tucumán Argentina
| | - Pablo Jayat
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
- Unidad Ejecutora Lillo Consejo Nacional de Investigaciones Científicas y Técnicas–Fundación Miguel Lillo San Miguel de Tucumán Argentina
| | - Gabriel Martin
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires Argentina
- Centro de Investigación Esquel de Montaña y Estepa Patagónica Consejo Nacional de Investigaciones Científicas y Técnicas‐Universidad Nacional de la Patagonia San Juan Bosco Esquel Argentina
- Laboratorio de Investigaciones en Evolución y Biodiversidad Facultad de Ciencias Naturales y Ciencias de la Salud Universidad Nacional de la Patagonia San Juan Bosco Esquel Argentina
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4
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Sinitsa MV, Čermák S, Kryuchkova LY. Cranial Anatomy of Csakvaromys bredai (Rodentia, Sciuridae, Xerinae) and Implications for Ground Squirrel Evolution and Systematics. J MAMM EVOL 2021. [DOI: 10.1007/s10914-021-09561-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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5
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Tracing the Paleobiology of Paedotherium and Tremacyllus (Pachyrukhinae, Notoungulata), the Latest Sciuromorph South American Native Ungulates – Part I: Snout and Masticatory Apparatus. J MAMM EVOL 2020. [DOI: 10.1007/s10914-020-09516-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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6
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Zelditch ML, Li J, Swiderski DL. Stasis of functionally versatile specialists. Evolution 2020; 74:1356-1377. [DOI: 10.1111/evo.13956] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 02/17/2020] [Accepted: 02/26/2020] [Indexed: 01/02/2023]
Affiliation(s)
| | - Jingchun Li
- Ecology and Evolutionary Biology University of Colorado Boulder Colorado 80309
| | - Donald L. Swiderski
- Kresge Hearing Research Institute and Museum of Zoology University of Michigan Ann Arbor Michigan 48109
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7
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Álvarez A, Ercoli MD, Olivares AI, De Santi NA, Verzi DH. Evolutionary Patterns of Mandible Shape Diversification of Caviomorph Rodents. J MAMM EVOL 2020. [DOI: 10.1007/s10914-020-09511-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Laakkonen J, Jernvall J. Muscles of Mastication and the Temporo-Mandibular Joint of the Saimaa (Pusa hispida saimensis) and Baltic (Pusa hispida botnica) Ringed Seals. ANN ZOOL FENN 2020. [DOI: 10.5735/086.057.0103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Juha Laakkonen
- Division of Veterinary Anatomy and Developmental Biology, Department of Veterinary Biosciences, Faculty of Veterinary Medicine, P.O. Box 66, FI-00014 University of Helsinki, Finland
| | - Jukka Jernvall
- Institute of Biotechnology, P.O. Box 56, FI-00014 University of Helsinki, Finland
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9
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Swanson MT, Oliveros CH, Esselstyn JA. A phylogenomic rodent tree reveals the repeated evolution of masseter architectures. Proc Biol Sci 2020; 286:20190672. [PMID: 31064307 DOI: 10.1098/rspb.2019.0672] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Understanding the number of times a trait has evolved is a necessary foundation for comprehending its potential relationships with selective regimes, developmental constraints and evolutionary diversification. Rodents make up over 40% of extant mammalian species, and their ecological and evolutionary success has been partially attributed to the increase in biting efficiency that resulted from a forward shift of one or two portions of the masseter muscle from the zygomatic arch onto the rostrum. This forward shift has occurred in three discrete ways, but the number of times it has occurred has never been explicitly quantified. We estimated an ultrametric phylogeny, the first to include all rodent families, using thousands of ultraconserved elements. We examined support for evolutionary relationships among the five rodent suborders and then incorporated relevant fossils, fitted models of character evolution, and used stochastic character mapping to determine that a portion of the masseter muscle has moved forward onto the rostrum at least seven times (with one reversal) during the approximately 70 Myr history of rodents. Combined, the repeated evolution of this key innovation, its increasing prevalence through time, and the species diversity of clades with this character underscores the adaptive value of improved biting efficiency and the relative ease with which some advantageous traits arise.
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Affiliation(s)
- Mark T Swanson
- Museum of Natural Science and Department of Biological Sciences, Louisiana State University , Baton Rouge, LA , USA
| | - Carl H Oliveros
- Museum of Natural Science and Department of Biological Sciences, Louisiana State University , Baton Rouge, LA , USA
| | - Jacob A Esselstyn
- Museum of Natural Science and Department of Biological Sciences, Louisiana State University , Baton Rouge, LA , USA
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Ercoli MD, Álvarez A, Candela AM. Sciuromorphy outside rodents reveals an ecomorphological convergence between squirrels and extinct South American ungulates. Commun Biol 2019; 2:202. [PMID: 31231692 PMCID: PMC6546766 DOI: 10.1038/s42003-019-0423-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 04/15/2019] [Indexed: 11/09/2022] Open
Abstract
Notoungulates were a diverse group of South American ungulates that included the rodent-like typotherians. However, they are typically compared with other ungulates and interpreted as grazers. Here we present the first detailed reconstruction of the masticatory muscles of the pachyrukhine typotherians Paedotherium and Tremacyllus. An outstanding feature is the presence of a true sciuromorph condition, defined by an anterior portion of the deep masseter muscle originating from a wide zygomatic plate that reaches the rostrum, a trait traceable since the Oligocene pachyrukhines. Consequently, pachyrukhines are the first case of sciuromorph non-rodent mammals. This morphology would have allowed them to explore ecological niches unavailable for the exclusively hystricomorph coexisting rodents. This innovative acquisition seems to be synchronous in Pachyrukhinae and sciuromorph rodents and related to hard-food consumption. We postulate the expansion of nut and cone trees during the major environmental changes at Eocene-Oligocene transition as a potential trigger for this convergence.
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Affiliation(s)
- Marcos D. Ercoli
- Instituto de Ecorregiones Andinas (INECOA), Universidad Nacional de Jujuy, CONICET, IdGyM, Av. Bolivia 1661, 4600 San Salvador de Jujuy, Jujuy Argentina
| | - Alicia Álvarez
- Instituto de Ecorregiones Andinas (INECOA), Universidad Nacional de Jujuy, CONICET, IdGyM, Av. Bolivia 1661, 4600 San Salvador de Jujuy, Jujuy Argentina
| | - Adriana M. Candela
- División de Paleontología de Vertebrados, Museo de La Plata, FCNyM, UNLP, CONICET, Paseo del Bosque s/n, 1900 La Plata, Buenos Aires Argentina
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11
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D’Elía G, Fabre PH, Lessa EP. Rodent systematics in an age of discovery: recent advances and prospects. J Mammal 2019. [DOI: 10.1093/jmammal/gyy179] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- Guillermo D’Elía
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Pierre-Henri Fabre
- Institut des Sciences de l’Evolution (ISEM, UMR 5554 CNRS-UM2-IRD), Université Montpellier, Montpellier Cedex 5, France
| | - Enrique P Lessa
- Departamento de Ecología y Evolución, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
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12
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Evolutionary and Functional Implications of Incisor Enamel Microstructure Diversity in Notoungulata (Placentalia, Mammalia). J MAMM EVOL 2019. [DOI: 10.1007/s10914-019-09462-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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13
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Adams NF, Rayfield EJ, Cox PG, Cobb SN, Corfe IJ. Functional tests of the competitive exclusion hypothesis for multituberculate extinction. ROYAL SOCIETY OPEN SCIENCE 2019; 6:181536. [PMID: 31032010 PMCID: PMC6458384 DOI: 10.1098/rsos.181536] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 02/21/2019] [Indexed: 05/08/2023]
Abstract
Multituberculate mammals thrived during the Mesozoic, but their diversity declined from the mid-late Paleocene onwards, becoming extinct in the late Eocene. The radiation of superficially similar, eutherian rodents has been linked to multituberculate extinction through competitive exclusion. However, characteristics providing rodents with a supposed competitive advantage are currently unknown and comparative functional tests between the two groups are lacking. Here, a multifaceted approach to craniomandibular biomechanics was taken to test the hypothesis that superior skull function made rodents more effective competitors. Digital models of the skulls of four extant rodents and the Upper Cretaceous multituberculate Kryptobaatar were constructed and used (i) in finite-element analysis to study feeding-induced stresses, (ii) to calculate metrics of bite force production and (iii) to determine mechanical resistances to bending and torsional forces. Rodents exhibit higher craniomandibular stresses and lower resistances to bending and torsion than the multituberculate, apparently refuting the competitive exclusion hypothesis. However, rodents optimize bite force production at the expense of higher skull stress and we argue that this is likely to have been more functionally and selectively important. Our results therefore provide the first functional lines of evidence for potential reasons behind the decline of multituberculates in the changing environments of the Paleogene.
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Affiliation(s)
- Neil F. Adams
- School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK
- Author for correspondence: Neil F. Adams e-mail:
| | - Emily J. Rayfield
- School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK
- Author for correspondence: Emily J. Rayfield e-mail:
| | - Philip G. Cox
- Department of Archaeology, University of York, York YO1 7EP, UK
- Centre for Anatomical and Human Sciences, Hull York Medical School, University of York, York YO10 5DD, UK
| | - Samuel N. Cobb
- Department of Archaeology, University of York, York YO1 7EP, UK
- Centre for Anatomical and Human Sciences, Hull York Medical School, University of York, York YO10 5DD, UK
| | - Ian J. Corfe
- Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
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Ginot S, Herrel A, Claude J, Hautier L. Morphometric models for estimating bite force in Mus and Rattus: mandible shape and size do better than lever-arm ratios. J Exp Biol 2019; 222:jeb.204867. [DOI: 10.1242/jeb.204867] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/13/2019] [Indexed: 11/20/2022]
Abstract
Morphological traits are frequently used as proxies for functional outputs such as bite force performance. This allows researchers to infer and interpret the impacts of functional variation, notably in adaptive terms. Despite their mechanical bases, the predictive power of these proxies for performance is not always tested. In particular, their accuracy at the intraspecific level is rarely assessed, and they have sometimes been shown to be unreliable. Here, we compare the performance of several morphological proxies in estimating in vivo bite force, across five species of murine rodents, at the interspecific and intraspecific levels. Proxies used include the size and shape of the mandible, as well as individual and combined muscular mechanical advantages (temporal, superficial masseter and deep masseter). Maximum voluntary bite force was measured in all individuals included. To test the accuracy of predictions allowed by the proxies, we combined linear regressions with a leave-one-out approach, estimating an individual bite force based on the rest of the dataset. The correlations between estimated values and the in vivo measurements were tested. At the interspecific and intraspecific levels, size and shape were better estimators than mechanical advantages. Mechanical advantage showed some predictive power at the interspecific level, but generally not within species, except for the deep masseter in Rattus. In few species, size and shape did not allow us to predict bite force. Extrapolations of performance based on mechanical advantage should therefore be used with care, and are mostly unjustified within species. In the latter case, size and shape are preferable.
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Affiliation(s)
- Samuel Ginot
- Institut des Sciences de l'Évolution de Montpellier (UMR5554), Montpellier, France
- Institut de Génomique Fonctionnelle de Lyon (UMR5242), Lyon, France
| | - Anthony Herrel
- Muséum National d'Histoire Naturelle (UMR7179), Paris, France
| | - Julien Claude
- Institut des Sciences de l'Évolution de Montpellier (UMR5554), Montpellier, France
| | - Lionel Hautier
- Institut des Sciences de l'Évolution de Montpellier (UMR5554), Montpellier, France
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15
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ITO K, ENDO H. The effect of the masticatory muscle physiological cross-sectional area on the structure of the temporomandibular joint in Carnivora. J Vet Med Sci 2019; 81:389-396. [PMID: 30674744 PMCID: PMC6451921 DOI: 10.1292/jvms.18-0611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
We compared the temporomandibular joint structure between species of the order Carnivora and investigated its variation among family lineages. We also investigated the effect of the
masticatory muscle physiological cross-sectional area (PCSA) on temporomandibular joint structure. The masticatory muscle is composed of multiple muscles, which contract in different
directions and exert pressure on the temporomandibular joint. We investigated the effect of the ratio of each muscle’s PCSA—an indicator of muscle force—and muscle size relative to body size
on temporomandibular joint structure. The temporalis PCSA relative to body size showed the highest correlation with temporomandibular joint structure. When the temporalis PCSA is large
relative to body size, the preglenoid projects caudally, the postglenoid projects rostrally and the pre-postglenoid angle interval is small, indicating that the condyle is locked in the
fossa to reinforce the temporomandibular joint. Most Carnivora use blade-like carnassial teeth when slicing food. However, dislocation occurs when the carnassial teeth are used by the
temporalis muscle. Our results suggest that the temporomandibular joint is reinforced to prevent dislocation caused by the temporalis muscle. In Mustelidae, the temporomandibular joint with
a rostrally projecting postglenoid is suitable for carnassial biting using the temporalis muscle. In Felidae, the force of the masseter onto the carnassial teeth is diverted to the canine by
tightening the temporomandibular joint. In Canidae, the masticatory muscle arrangement is well-balanced, enabling combined action. Hence, reinforcement of the temporomandibular joint by bone
structure is unnecessary.
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Affiliation(s)
- Kai ITO
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- The University Museum, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033, Japan
| | - Hideki ENDO
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- The University Museum, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033, Japan
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Jones K, Law CJ. Differentiation of craniomandibular morphology in two sympatric Peromyscus mice (Cricetidae: Rodentia). MAMMAL RES 2018. [DOI: 10.1007/s13364-018-0364-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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17
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Ginot S, Herrel A, Claude J, Hautier L. Skull Size and Biomechanics are Good Estimators of In Vivo
Bite Force in Murid Rodents. Anat Rec (Hoboken) 2018; 301:256-266. [DOI: 10.1002/ar.23711] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 07/31/2017] [Accepted: 08/24/2017] [Indexed: 11/05/2022]
Affiliation(s)
- Samuel Ginot
- Institut des Sciences de l'Evolution de Montpellier; Université de Montpellier; Montpellier France
| | | | - Julien Claude
- Institut des Sciences de l'Evolution de Montpellier; Université de Montpellier; Montpellier France
| | - Lionel Hautier
- Institut des Sciences de l'Evolution de Montpellier; Université de Montpellier; Montpellier France
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18
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Gomes Rodrigues H, Cornette R, Clavel J, Cassini G, Bhullar BAS, Fernández-Monescillo M, Moreno K, Herrel A, Billet G. Differential influences of allometry, phylogeny and environment on the rostral shape diversity of extinct South American notoungulates. ROYAL SOCIETY OPEN SCIENCE 2018; 5:171816. [PMID: 29410874 PMCID: PMC5792951 DOI: 10.1098/rsos.171816] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 12/21/2017] [Indexed: 05/15/2023]
Abstract
Understanding the mechanisms responsible for phenotypic diversification, and the associated underlying constraints and ecological factors represents a central issue in evolutionary biology. Mammals present a wide variety of sizes and shapes, and are characterized by a high number of morphological convergences that are hypothesized to reflect similar environmental pressures. Extinct South American notoungulates evolved in isolation from northern mammalian faunas in highly disparate environments. They present a wide array of skeletal phenotypes and convergences, such as ever-growing dentition. Here, we focused on the origins of the rostral diversity of notoungulates by quantifying the shape of 26 genera using three-dimensional geometric morphometric analysis. We tested the influence of allometry and phylogeny on rostral shape and evaluated rates of evolutionary change in the different clades. We found strong allometric and phylogenetic signals concerning the rostral shape of notoungulates. Despite convergent forms, we observed a diffuse diversification of rostral shape, with no significant evidence of influence by large-scaled environmental variation. This contrasts with the increase in dental crown height that occurred in four late-diverging families in response to similar environmental pressures. These results illustrate the importance of considering both biological components and evolutionary rates to better understand some aspects of phenotypic diversity.
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Affiliation(s)
- Helder Gomes Rodrigues
- Centre de Recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), UMR CNRS 7207, CP38, Muséum National d'Histoire Naturelle, Univ Paris 6, 8 rue Buffon, 75005 Paris, France
- Mécanismes adaptatifs et évolution (MECADEV), UMR 7179, CNRS, Funevol team, Muséum National d'Histoire Naturelle, 55 rue Buffon, Bat. Anatomie Comparée, CP 55, 75005, Paris Cedex 5, France
- Author for correspondence: Helder Gomes Rodrigues e-mail:
| | - Raphaël Cornette
- Institut de Systématique, Evolution, Biodiversité (ISYEB UMR 7205), MNHN, CNRS, UPMC, CP26, Sorbonne Universités, 57 rue Cuvier, 75005 Paris, France
| | - Julien Clavel
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, Ecole Normale Supérieure, Paris Sciences et Lettres (PSL), Research University, 75005 Paris, France
| | - Guillermo Cassini
- División Mastozoología, Museo Argentino de Ciencias Naturales ‘‘Bernardino Rivadavia’’(MACN), Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Ciencias Básicas, Universidad Nacional de Luján (UNLu), Luján, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Yale University, PO Box 208109, New Haven, CT 06520, USA
| | - Bhart-Anjan S. Bhullar
- Department of Geology and Geophysics, Yale University, PO Box 208109, New Haven, CT 06520, USA
- Peabody Museum of Natural History, Yale University, 170 Whitney Avenue, New Haven, CT 06511, USA
| | - Marcos Fernández-Monescillo
- Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (IANIGLA), CCT–CONICET–Mendoza, Avenida Ruiz Leal s/n, Parque Gral, San Martín 5500, Mendoza, Argentina
| | - Karen Moreno
- Instituto de Ciencias de la Tierra, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Anthony Herrel
- Mécanismes adaptatifs et évolution (MECADEV), UMR 7179, CNRS, Funevol team, Muséum National d'Histoire Naturelle, 55 rue Buffon, Bat. Anatomie Comparée, CP 55, 75005, Paris Cedex 5, France
| | - Guillaume Billet
- Centre de Recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), UMR CNRS 7207, CP38, Muséum National d'Histoire Naturelle, Univ Paris 6, 8 rue Buffon, 75005 Paris, France
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19
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Cox PG. The jaw is a second-class lever in Pedetes capensis (Rodentia: Pedetidae). PeerJ 2017; 5:e3741. [PMID: 28875081 PMCID: PMC5581530 DOI: 10.7717/peerj.3741] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 08/05/2017] [Indexed: 11/23/2022] Open
Abstract
The mammalian jaw is often modelled as a third-class lever for the purposes of biomechanical analyses, owing to the position of the resultant muscle force between the jaw joint and the teeth. However, it has been proposed that in some rodents the jaws operate as a second-class lever during distal molar bites, owing to the rostral position of the masticatory musculature. In particular, the infraorbital portion of the zygomatico-mandibularis (IOZM) has been suggested to be of major importance in converting the masticatory system from a third-class to a second-class lever. The presence of the IOZM is diagnostic of the hystricomorph rodents, and is particularly well-developed in Pedetes capensis, the South African springhare. In this study, finite element analysis (FEA) was used to assess the lever mechanics of the springhare masticatory system, and to determine the function of the IOZM. An FE model of the skull of P. capensis was constructed and loaded with all masticatory muscles, and then solved for biting at each tooth in turn. Further load cases were created in which each masticatory muscle was removed in turn. The analyses showed that the mechanical advantage of the springhare jaws was above one at all molar bites and very close to one during the premolar bite. Removing the IOZM or masseter caused a drop in mechanical advantage at all bites, but affected strain patterns and cranial deformation very little. Removing the ZM had only a small effect on mechanical advantage, but produced a substantial reduction in strain and deformation across the skull. It was concluded that the masticatory system of P. capensis acts as a second class lever during bites along almost the entire cheek tooth row. The IOZM is clearly a major contributor to this effect, but the masseter also has a part to play. The benefit of the IOZM is that it adds force without substantially contributing to strain or deformation of the skull. This may help explain why the hystricomorphous morphology has evolved multiple times independently within Rodentia.
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Affiliation(s)
- Philip G Cox
- Department of Archaeology, University of York, York, UK.,Hull York Medical School, University of York, York, UK
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Doronina L, Matzke A, Churakov G, Stoll M, Huge A, Schmitz J. The Beaver's Phylogenetic Lineage Illuminated by Retroposon Reads. Sci Rep 2017; 7:43562. [PMID: 28256552 PMCID: PMC5335264 DOI: 10.1038/srep43562] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 01/25/2017] [Indexed: 11/18/2022] Open
Abstract
Solving problematic phylogenetic relationships often requires high quality genome data. However, for many organisms such data are still not available. Among rodents, the phylogenetic position of the beaver has always attracted special interest. The arrangement of the beaver's masseter (jaw-closer) muscle once suggested a strong affinity to some sciurid rodents (e.g., squirrels), placing them in the Sciuromorpha suborder. Modern molecular data, however, suggested a closer relationship of beaver to the representatives of the mouse-related clade, but significant data from virtually homoplasy-free markers (for example retroposon insertions) for the exact position of the beaver have not been available. We derived a gross genome assembly from deposited genomic Illumina paired-end reads and extracted thousands of potential phylogenetically informative retroposon markers using the new bioinformatics coordinate extractor fastCOEX, enabling us to evaluate different hypotheses for the phylogenetic position of the beaver. Comparative results provided significant support for a clear relationship between beavers (Castoridae) and kangaroo rat-related species (Geomyoidea) (p < 0.0015, six markers, no conflicting data) within a significantly supported mouse-related clade (including Myodonta, Anomaluromorpha, and Castorimorpha) (p < 0.0015, six markers, no conflicting data).
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Affiliation(s)
- Liliya Doronina
- Institute of Experimental Pathology (ZMBE), University of Münster, Münster, Germany
| | - Andreas Matzke
- Institute of Experimental Pathology (ZMBE), University of Münster, Münster, Germany
| | - Gennady Churakov
- Institute of Experimental Pathology (ZMBE), University of Münster, Münster, Germany
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
| | - Monika Stoll
- Core Facility Genomics, Medical Faculty, University of Münster, Münster, Germany
| | - Andreas Huge
- Core Facility Genomics, Medical Faculty, University of Münster, Münster, Germany
| | - Jürgen Schmitz
- Institute of Experimental Pathology (ZMBE), University of Münster, Münster, Germany
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Mancinelli E, Capello V. Anatomy and Disorders of the Oral Cavity of Rat-like and Squirrel-like Rodents. Vet Clin North Am Exot Anim Pract 2016; 19:871-900. [PMID: 27497210 PMCID: PMC7110795 DOI: 10.1016/j.cvex.2016.04.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The order Rodentia comprises more than 2000 species divided into 3 groups based on anatomic and functional differences of the masseter muscle. Myomorph and sciuromorph species have elodont incisors and anelodont cheek teeth, unlike hystrichomorph species which have full anelodont dentition. Diseases of incisors and cheek teeth of rat-like and squirrel-like rodents result in a wide variety of symptoms and clinical signs. Appropriate diagnostic testing and imaging techniques are required to obtain a definitive diagnosis, formulate a prognosis, and develop a treatment plan. A thorough review of elodontoma, odontoma, and pseudo-odontoma is provided, including treatment of pseudo-odontomas in prairie dogs.
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Affiliation(s)
- Elisabetta Mancinelli
- Bath Referrals, Rosemary Lodge Veterinary Hospital, Bath, Wellsway, Somerset BA2 5RL, UK.
| | - Vittorio Capello
- Clinica Veterinaria S.Siro, Via Lampugnano, 99, Milano 20151, Italy; Clinica Veterinaria Gran Sasso, Via Donatello, 26, Milano 20134, Italy
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Maestri R, Patterson BD, Fornel R, Monteiro LR, de Freitas TRO. Diet, bite force and skull morphology in the generalist rodent morphotype. J Evol Biol 2016; 29:2191-2204. [DOI: 10.1111/jeb.12937] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/17/2016] [Accepted: 07/05/2016] [Indexed: 01/23/2023]
Affiliation(s)
- R. Maestri
- Programa de Pós-Graduação em Ecologia; Universidade Federal do Rio Grande do Sul; Porto Alegre RS Brazil
| | - B. D. Patterson
- Integrative Research Center; Field Museum of Natural History; Chicago IL USA
| | - R. Fornel
- Programa de Pós-Graduação em Ecologia; Universidade Regional Integrada do Alto Uruguai e das Missões; Erechim RS Brazil
| | - L. R. Monteiro
- Laboratório de Ciências Ambientais; CBB; Universidade Estadual do Norte Fluminense; Campos dos Goytacazes RJ Brazil
| | - T. R. O. de Freitas
- Programa de Pós-Graduação em Ecologia; Universidade Federal do Rio Grande do Sul; Porto Alegre RS Brazil
- Departamento de Genética; Universidade Federal do Rio Grande do Sul; Porto Alegre RS Brazil
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Cox PG, Baverstock H. Masticatory Muscle Anatomy and Feeding Efficiency of the American Beaver, Castor canadensis (Rodentia, Castoridae). J MAMM EVOL 2015. [DOI: 10.1007/s10914-015-9306-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Cox PG, Rinderknecht A, Blanco RE. Predicting bite force and cranial biomechanics in the largest fossil rodent using finite element analysis. J Anat 2015; 226:215-23. [PMID: 25652795 DOI: 10.1111/joa.12282] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2015] [Indexed: 11/27/2022] Open
Abstract
Josephoartigasia monesi, from the Pliocene of Uruguay, is the largest known fossil rodent, with an estimated body mass of 1000 kg. In this study, finite element analysis was used to estimate the maximum bite force that J. monesi could generate at the incisors and the cheek teeth. Owing to uncertainty in the model inputs, a sensitivity study was conducted in which the muscle forces and orientations were sequentially altered. This enabled conclusions to be drawn on the function of some of the masticatory muscles. It was found that J. monesi had a bite of 1389 N at the incisors, rising to 4165 N at the third molar. Varying muscle forces by 20% and orientations by 10° around the medio-lateral aspect led to an error in bite force of under 35% at each tooth. Predicted stresses across the skull were only minimally affected by changes to muscle forces and orientations, but revealed a reasonable safety factor in the strength of the skull. These results, combined with previous work, lead us to speculate that J. monesi was behaving in an elephant-like manner, using its incisors like tusks, and processing tough vegetation with large bite forces at the cheek teeth.
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Affiliation(s)
- Philip G Cox
- Department of Archaeology and Hull York Medical School, University of York, York, UK
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Gerstner GE, Madhavan S, Braun TM. Relationships between masticatory rhythmicity, body mass and cephalometrically-determined aesthetic and functional variables during development in humans. Arch Oral Biol 2014; 59:711-21. [PMID: 24798980 DOI: 10.1016/j.archoralbio.2014.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/09/2014] [Accepted: 04/13/2014] [Indexed: 11/24/2022]
Abstract
OBJECTIVE We studied the relationship between chewing rhythmicity, craniomandibular morphology, and age in humans. DESIGN Sixty subjects (10M:10F/group×three age groups, viz., 4-8, 10-14, and 17-21 years) participated. Subjects chewed gum for 2min while jaw movements in the frontal plane were videorecorded. Mean and variation in mean chewing cycle duration (TC) were quantified using maximum opening to maximum opening as cycle boundaries. Five "aesthetic" cephalometric variables (e.g., ANB) and seven "functional" variables (e.g., jaw length) were quantified from subjects' lateral cephalographs. Simple linear regression models and several multivariate analyses were used in comparisons. RESULTS Mean TC increased and variation in TC decreased significantly with age. Body mass correlated with age, height, TC, all seven "functional" variables and only two "aesthetic" variables. Mean TC was correlated significantly with jaw length, distance from condylion to first molar point, distance from gonion to zygomatic arch, and distance from hyoid to menton. CONCLUSIONS TC appeared to adapt with age. Although TC scaled most significantly with age, it is more likely that TC is mechanistically linked to jaw length or size. The decrease in TC variation with age suggests improved efficiency. TC did not scale with "aesthetic" variables, suggesting that these do not impact chewing rate; however, clinical procedures that impact jaw length may. The negative allometric scaling of TC with "functional" variables may reflect the pedomorphic jaw and face of humans. Further human studies will provide insights into the nature of scaling and adaptation of rhythmic chewing during development.
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Affiliation(s)
- Geoffrey E Gerstner
- Department of Biologic and Materials Sciences, School of Dentistry, 1011 North University, University of Michigan, Ann Arbor, MI 48109-1078, USA; Department of Psychology, University of Michigan, Ann Arbor, MI 48109-1043, USA.
| | - Shashi Madhavan
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, 1011 North University, University of Michigan, Ann Arbor, MI 48109-1078, USA
| | - Thomas M Braun
- Department of Biostatistics, M4063 School of Public Health II, 1415 Washington Heights, University of Michigan, Ann Arbor, MI 48109-2029, USA.
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Baverstock H, Jeffery NS, Cobb SN. The morphology of the mouse masticatory musculature. J Anat 2013; 223:46-60. [PMID: 23692055 PMCID: PMC4487762 DOI: 10.1111/joa.12059] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2013] [Indexed: 01/07/2023] Open
Abstract
The mouse has been the dominant model organism in studies on the development, genetics and evolution of the mammalian skull and associated soft-tissue for decades. There is the potential to take advantage of this well studied model and the range of mutant, knockin and knockout organisms with diverse craniofacial phenotypes to investigate the functional significance of variation and the role of mechanical forces on the development of the integrated craniofacial skeleton and musculature by using computational mechanical modelling methods (e.g. finite element and multibody dynamic modelling). Currently, there are no detailed published data of the mouse masticatory musculature available. Here, using a combination of micro-dissection and non-invasive segmentation of iodine-enhanced micro-computed tomography, we document the anatomy, architecture and proportions of the mouse masticatory muscles. We report on the superficial masseter (muscle, tendon and pars reflecta), deep masseter, zygomaticomandibularis (anterior, posterior, infraorbital and tendinous parts), temporalis (lateral and medial parts), external and internal pterygoid muscles. Additionally, we report a lateral expansion of the attachment of the temporalis onto the zygomatic arch, which may play a role in stabilising this bone during downwards loading. The data presented in this paper now provide a detailed reference for phenotypic comparison in mouse models and allow the mouse to be used as a model organism in biomechanical and functional modelling and simulation studies of the craniofacial skeleton and particularly the masticatory system.
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Affiliation(s)
- Hester Baverstock
- Centre for Anatomical and Human Sciences, Hull York Medical School, University of Hull, Hull, UK.
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Furuuchi K, Koyabu D, Mori K, Endo H. Physiological Cross-Sectional Area of the Masticatory Muscles in the Giraffe (Giraffa camelopardalis). MAMMAL STUDY 2013. [DOI: 10.3106/041.038.0109] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Herrel A, Fabre AC, Hugot JP, Keovichit K, Adriaens D, Brabant L, Van Hoorebeke L, Cornette R. Ontogeny of the cranial system in Laonastes aenigmamus. J Anat 2012; 221:128-37. [PMID: 22607030 PMCID: PMC3406360 DOI: 10.1111/j.1469-7580.2012.01519.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2012] [Indexed: 10/28/2022] Open
Abstract
Rodents, together with bats, are among the ecologically most diverse and most speciose groups of mammals. Moreover, rodents show elaborate specializations of the feeding apparatus in response to the predominantly fore-aft movements of the lower jaw. The Laotian rock rat Laonastes aenigmamus was recently discovered and originally thought to belong to a new family. The difficulties in classifying L. aenigmamus based on morphological characters stem from the fact that it presents a mixture of sciurognathous and hystricognathous characteristics, including the morphology of the jaw adductors. The origin of the unusual muscular organization in this species remains, however, unclear. Here, we investigate the development of the masticatory system in Laonastes to better understand the origin of its derived morphology relative to other rodents. Our analyses show that skull and mandible development is characterized by an overall elongation of the snout region. Muscle mass increases with positive allometry during development and growth, and so does the force-generating capacity of the jaw adductor muscles (i.e. physiological cross-sectional area). Whereas fetal crania and musculature are more similar to those of typical rodents, adults diverge in the elongation of the rostral part of the skull and the disproportionate development of the zygomaticomandibularis. Our data suggest a functional signal in the development of the unusual cranial morphology, possibly associated with the folivorous trophic ecology of the species.
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Affiliation(s)
- Anthony Herrel
- UMR CNRS/MNHN 7179, Mécanismes adaptatifs: des organismes aux communautés, Paris, France.
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Cox PG, Rayfield EJ, Fagan MJ, Herrel A, Pataky TC, Jeffery N. Functional evolution of the feeding system in rodents. PLoS One 2012; 7:e36299. [PMID: 22558427 PMCID: PMC3338682 DOI: 10.1371/journal.pone.0036299] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 04/04/2012] [Indexed: 11/18/2022] Open
Abstract
The masticatory musculature of rodents has evolved to enable both gnawing at the incisors and chewing at the molars. In particular, the masseter muscle is highly specialised, having extended anteriorly to originate from the rostrum. All living rodents have achieved this masseteric expansion in one of three ways, known as the sciuromorph, hystricomorph and myomorph conditions. Here, we used finite element analysis (FEA) to investigate the biomechanical implications of these three morphologies, in a squirrel, guinea pig and rat. In particular, we wished to determine whether each of the three morphologies is better adapted for either gnawing or chewing. Results show that squirrels are more efficient at muscle-bite force transmission during incisor gnawing than guinea pigs, and that guinea pigs are more efficient at molar chewing than squirrels. This matches the known diet of nuts and seeds that squirrels gnaw, and of grasses that guinea pigs grind down with their molars. Surprisingly, results also indicate that rats are more efficient as well as more versatile feeders than both the squirrel and guinea pig. There seems to be no compromise in biting efficiency to accommodate the wider range of foodstuffs and the more general feeding behaviour adopted by rats. Our results show that the morphology of the skull and masticatory muscles have allowed squirrels to specialise as gnawers and guinea pigs as chewers, but that rats are high-performance generalists, which helps explain their overwhelming success as a group.
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Affiliation(s)
- Philip G Cox
- Hull York Medical School, University of Hull, Hull, United Kingdom.
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Cox PG, Fagan MJ, Rayfield EJ, Jeffery N. Finite element modelling of squirrel, guinea pig and rat skulls: using geometric morphometrics to assess sensitivity. J Anat 2011; 219:696-709. [PMID: 21974720 DOI: 10.1111/j.1469-7580.2011.01436.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Rodents are defined by a uniquely specialized dentition and a highly complex arrangement of jaw-closing muscles. Finite element analysis (FEA) is an ideal technique to investigate the biomechanical implications of these specializations, but it is essential to understand fully the degree of influence of the different input parameters of the FE model to have confidence in the model's predictions. This study evaluates the sensitivity of FE models of rodent crania to elastic properties of the materials, loading direction, and the location and orientation of the models' constraints. Three FE models were constructed of squirrel, guinea pig and rat skulls. Each was loaded to simulate biting on the incisors, and the first and the third molars, with the angle of the incisal bite varied over a range of 45°. The Young's moduli of the bone and teeth components were varied between limits defined by findings from our own and previously published tests of material properties. Geometric morphometrics (GMM) was used to analyse the resulting skull deformations. Bone stiffness was found to have the strongest influence on the results in all three rodents, followed by bite position, and then bite angle and muscle orientation. Tooth material properties were shown to have little effect on the deformation of the skull. The effect of bite position varied between species, with the mesiodistal position of the biting tooth being most important in squirrels and guinea pigs, whereas bilateral vs. unilateral biting had the greatest influence in rats. A GMM analysis of isolated incisor deformations showed that, for all rodents, bite angle is the most important parameter, followed by elastic properties of the tooth. The results here elucidate which input parameters are most important when defining the FE models, but also provide interesting glimpses of the biomechanical differences between the three skulls, which will be fully explored in future publications.
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Affiliation(s)
- P G Cox
- Department of Musculoskeletal Biology, University of Liverpool, Liverpool, UK.
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Wall CE, Vinyard CJ, Williams SH, Gapeyev V, Liu X, Lapp H, German RZ. Overview of FEED, the feeding experiments end-user database. Integr Comp Biol 2011; 51:215-23. [PMID: 21700574 PMCID: PMC3135827 DOI: 10.1093/icb/icr047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Feeding Experiments End-user Database (FEED) is a research tool developed by the Mammalian Feeding Working Group at the National Evolutionary Synthesis Center that permits synthetic, evolutionary analyses of the physiology of mammalian feeding. The tasks of the Working Group are to compile physiologic data sets into a uniform digital format stored at a central source, develop a standardized terminology for describing and organizing the data, and carry out a set of novel analyses using FEED. FEED contains raw physiologic data linked to extensive metadata. It serves as an archive for a large number of existing data sets and a repository for future data sets. The metadata are stored as text and images that describe experimental protocols, research subjects, and anatomical information. The metadata incorporate controlled vocabularies to allow consistent use of the terms used to describe and organize the physiologic data. The planned analyses address long-standing questions concerning the phylogenetic distribution of phenotypes involving muscle anatomy and feeding physiology among mammals, the presence and nature of motor pattern conservation in the mammalian feeding muscles, and the extent to which suckling constrains the evolution of feeding behavior in adult mammals. We expect FEED to be a growing digital archive that will facilitate new research into understanding the evolution of feeding anatomy.
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Affiliation(s)
- Christine E Wall
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708, USA.
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Cox PG, Jeffery N. Reviewing the Morphology of the Jaw-Closing Musculature in Squirrels, Rats, and Guinea Pigs with Contrast-Enhanced MicroCt. Anat Rec (Hoboken) 2011; 294:915-28. [DOI: 10.1002/ar.21381] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 02/17/2011] [Indexed: 12/30/2022]
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