20 research outputs found

    Processing Matters: 3D Mesh Morphology

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    Substantive advancements have been made toward automating the application of landmarks and semilandmarks. These approaches can aid in expediting the landmarking process, while simultaneously reducing landmarking errors and investigator bias. This study enlists a template-based approach to quantify deviations in mesh processing outputs using a Pontchartrain dart point from the collections of the National Forests and Grasslands in Texas, which was scanned and processed at multiple resolutions using microCT and laser scanners. Following data collection and output, meshes were processed using an automated and replicable workflow. A batch processing protocol was developed in Geomagic Design X and Control X to facilitate exploratory comparisons of the processed meshes, which indicated that the greatest changes to the meshes occurred along the lateral margins of the dart point. Results of the geometric morphometric study evince implications for processed meshes curated in digital repositories. Investigators that endeavour to incorporate curated meshes should begin with the unprocessed data, enlist uniform processing protocols across the sample, and comprehend the many vagaries of 3D data collection and processing across different modalities

    Importance of the Quatrehomme collection (Monnaye Museum, Meung-sur-Loire) in the French palaeontological landscape

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    La collection Quatrehomme est décrite par Ginsburg comme étant "modeste à trÚs modeste". Cependant, il n'existe aucun inventaire précis pour juger de la taille de cette collection. Afin de mieux comprendre son importance, un inventaire des restes de mammifÚres est en cours. Dans l'état actuel de l'inventaire, 35 localités différentes ont été recensées, principalement dans le Bassin de Savigné-sur-Lathan. 3266 spécimens, couvrant huit des neuf ordres de mammifÚres terrestres trouvés dans les Faluns, sont actuellement identifiés dans l'ensemble de la collection inventoriée. La collection Hartmann, hébergée au Musée du Savignéen à Savigné-sur-Lathan, est aujourd'hui considérée par différents auteurs comme une collection "importante" par sa taille (1475 restes de mammifÚres marins et terrestres). La collection Bourgeois, collection majeure et de référence (aujourd'hui répartie dans différents musées) en compte 1850. Nous estimons que la collection Quatrehomme comprend plus de 7500 spécimens de mammifÚres terrestres. Il s'agit de la plus grande collection connue de Pliopithecus (25 spécimens) et de Lagomorpha (1355 spécimens) des Faluns. Huit spécimens de Tapiroidea (y compris une mùchoire portant des dents) et trois spécimens de Chalicotherium sont inventoriés. Aujourd'hui, la collection Quatrehomme est en cours d'étude et devrait occuper ainsi une place de plus en plus importante dans le paysage paléontologique français dans les années à venir.The Quatrehomme collection is described by Ginsburg as "modest to very modest" and there is no accurate inventory. In order to highlight this collection and better understand its importance, an inventory of the terrestrial mammal remains is in progress. In the current state of the inventory 35 different locations were identified, mostly in the Savigné-sur-Lathan Basin. 3,266 specimens, covering 8 of the 9 orders of terrestrial mammals found in the Faluns, are currently registered in the data set. To date, the most impressive published Faluns mammal collections are from Hartmann, hosted at the volunteer "Musée du Savignéen" (Savigné-sur-Lathan) and Bourgeois (today splitted in different museums). While this Hartmann's collection contains 1,475 mammal remains (marine and terrestrial) and Bourgeois' one 1850 (only terrestrial), we estimate that the Quatrehomme collection encompasses more than 7,500 terrestrial specimens. It is the largest known Faluns collection of Pliopithecus (25 specimens) and of Lagomorpha (1,355 specimens). Also, eight Tapiroidea specimens (including a jaw with teeth) and three Chalicotherium remains are inventoried. This collection is now being studied in detail. In the next few years it will take a more prominent place in the French paleontological landscape

    A GWAS in Latin Americans identifies novel face shape loci, implicating VPS13B and a Denisovan introgressed region in facial variation

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    To characterize the genetic basis of facial features in Latin Americans, we performed a genome-wide association study (GWAS) of more than 6000 individuals using 59 landmark-based measurements from two-dimensional profile photographs and ~9,000,000 genotyped or imputed single-nucleotide polymorphisms. We detected significant association of 32 traits with at least 1 (and up to 6) of 32 different genomic regions, more than doubling the number of robustly associated face morphology loci reported until now (from 11 to 23). These GWAS hits are strongly enriched in regulatory sequences active specifically during craniofacial development. The associated region in 1p12 includes a tract of archaic adaptive introgression, with a Denisovan haplotype common in Native Americans affecting particularly lip thickness. Among the nine previously unidentified face morphology loci we identified is the VPS13B gene region, and we show that variants in this region also affect midfacial morphology in mice

    Postnatal development and evolution of the rodents' craniofacial complex

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    Understanding developmental mechanisms in evolution is crucial to apprehend the diversification of organismal forms. In mammals, changes occur during all development phases (prenatal and postnatal). Postnatal growth plays an essential role in the acquisition of the adult shape. During this period, the craniofacial complex undergoes many changes in functional constraint forcing the different tissue to accommodate while adjusting, along the growth and at the adult stage, to a certain level of functional performance. These different developmental interactions respond to several influencing factors such as molecular, genetic and cellular processes but also the environment. The latter will play on these interactions, but in different ways between the prenatal and postnatal phases, as gestational environment and environment at birth are different. For testing the interactions between the developing organism and its environment and the potential evolutionary consequences, Rodentia is a good example of broad diversity in all aspects (wide variety of forms, in diets, behavior and ecology) and thus a study group of choice. It is a very diverse and disparate mammal order, in which changes can be observed on a large scale. In addition, it includes model organisms that can be easily reared in laboratory following a precise experimental configuration to test the effects of diverse sources of variation. The craniofacial complex is a highly integrated structure, architecturally complex, as it is composed of many skeletal elements, and functionally, as it is involved in various tasks essential to the organism. At the same time, and somewhat paradoxically, this unit is highly scalable and presents a great diversity of forms. The basis of craniofacial shape variation and its control are as much, related to the additive effects of genes as to their epigenetic and context-specific interactions during development. These epigenetic interactions during growth will respond to mechanical and other stimuli between the ossification centers, the tissues and organs making up the head. In particular, these interactions control the spatialization and intensity of bone remodeling in response to other tissue strain. They will thus compensate and coordinate the growth of the different tissues and organs in order to acquire and/or maintain certain functions, such as the occlusion between the upper and lower jaws. These epigenetic interactions are thus essential to the normal development of the skeleton in general and the skull in particular. By responding to changes in forces and movements, they will be a potential driver of microevolutionary changes (and thus macroevolutionary changes) at the morphological level favoring adaptive directions of variation and generating new functional covariations between traits. Despite this central role, the importance of these interactions in the expression of inter-specific differences and in the longer term in the dynamics of clades remains poorly understood. Analysis of the tempo of adult disparity acquisition during ontogeny is a key element in understanding the differential filling of the shape space by clades. This project aimed I) at studying the establishment of craniofacial disparity in rodents during development on a macroevolutionary scale and then on a finer taxonomic scale; and II) at estimating the importance of the epigenetic processes during this postnatal growth.La comprĂ©hension des mĂ©canismes de dĂ©veloppement dans l’évolution est cruciale pour apprĂ©hender la diversification des organismes. Chez les mammifĂšres, des changements se produisent tout au long du dĂ©veloppement (prĂ©natal et postnatal). La croissance postnatale joue un rĂŽle essentiel dans l’acquisition de la forme adulte. Durant cette pĂ©riode, le complexe craniofacial subit de nombreux changements de contraintes fonctionnelles obligeant les diffĂ©rents tissus Ă  s’adapter tout en s’ajustant, tout au long de la croissance et au stade adulte, Ă  un certain niveau de performance fonctionnelle. Ces diffĂ©rentes interactions dĂ©veloppementales rĂ©pondent Ă  plusieurs facteurs forçants tels que les processus molĂ©culaires, gĂ©nĂ©tiques et cellulaires mais aussi l’environnement. Ce dernier va jouer sur ces interactions, mais de maniĂšre diffĂ©rente entre les phases prĂ©natale et postnatale, car l’environnement gestationnel et l’environnement Ă  la naissance sont diffĂ©rents. Pour tester les interactions entre l’organisme en dĂ©veloppement et son environnement et les consĂ©quences potentielles sur l’évolution, les Rodentia constituent un bon exemple de grande diversitĂ© Ă  tous Ă©gards (grande variĂ©tĂ© de formes, de rĂ©gimes alimentaires, de comportements et d’écologie) et donc un groupe d’étude de choix. Il s’agit d’un ordre de mammifĂšres trĂšs diversifiĂ© et disparate, dans lequel des changements peuvent ĂȘtre observĂ©s Ă  grande Ă©chelle. En outre, ce groupe comprend plusieurs organismes modĂšles qui peuvent ĂȘtre facilement Ă©levĂ©s en laboratoire, afin de tester les effets de diverses sources de variation grĂące Ă  des protocoles expĂ©rimentaux prĂ©cis. Le complexe craniofacial est une structure hautement intĂ©grĂ©e, complexe sur le plan architectural, car il est composĂ© de nombreux Ă©lĂ©ments squelettiques, et sur le plan fonctionnel, car il participe Ă  diverses tĂąches essentielles pour l’organisme. En mĂȘme temps, et de façon quelque peu paradoxale, cet ensemble est trĂšs Ă©volvable et prĂ©sente une grande diversitĂ© de formes. La base de la variation de la forme craniofaciale et son contrĂŽle sont autant liĂ©s aux effets additifs des gĂšnes qu’à leurs interactions Ă©pigĂ©nĂ©tiques et contextuelles au cours du dĂ©veloppement. Ces interactions Ă©pigĂ©nĂ©tiques pendant la croissance vont rĂ©pondre aux stimuli mĂ©caniques et autres, entre les centres d’ossification, les tissus et les organes qui composent la tĂȘte. En particulier, ces interactions contrĂŽlent la spatialisation et l’intensitĂ© du remodelage osseux en rĂ©ponse aux contraintes subies par les autres tissus. Elles vont ainsi compenser et coordonner la croissance des diffĂ©rents tissus et organes afin d’acquĂ©rir et/ou de maintenir certaines fonctions, comme l’occlusion entre les mĂąchoires supĂ©rieure et infĂ©rieure. Ces interactions Ă©pigĂ©nĂ©tiques sont donc essentielles au dĂ©veloppement normal du squelette en gĂ©nĂ©ral et du crĂąne en particulier. En rĂ©pondant aux changements de forces et de mouvements, elles seront un moteur potentiel de changements microĂ©volutifs (et donc macroĂ©volutifs) au niveau morphologique favorisant des directions adaptatives de variation et gĂ©nĂ©rant de nouvelles covariations fonctionnelles entre les traits. MalgrĂ© ce rĂŽle central, l’importance de ces interactions dans l’expression des diffĂ©rences interspĂ©cifiques et Ă  plus long terme dans la dynamique des clades reste mal comprise. L’analyse du rythme d’acquisition de la disparitĂ© chez l’adulte au cours de l’ontogenĂšse est un Ă©lĂ©ment clĂ© pour comprendre le remplissage diffĂ©rentiel de l’espace des formes par les clades. Ce projet a visĂ© Ă  Ă©tudier I) la mise en place de la disparitĂ© craniofaciale chez les rongeurs au cours du dĂ©veloppement Ă  Ă©chelle macroĂ©volutive, puis Ă  une Ă©chelle taxonomique plus fine ; et II) d’évaluer l’importance des processus Ă©pigĂ©nĂ©tiques lors de cette croissance postnatale

    DĂ©veloppement postnatal et Ă©volution du complexe craniofacial chezles rongeurs

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    La comprĂ©hension des mĂ©canismes de dĂ©veloppement dans l’évolution est cruciale pour apprĂ©hender la diversification des organismes. Chez les mammifĂšres, des changements se produisent tout au long du dĂ©veloppement (prĂ©natal et postnatal). La croissance postnatale joue un rĂŽle essentiel dans l’acquisition de la forme adulte. Durant cette pĂ©riode, le complexe craniofacial subit de nombreux changements de contraintes fonctionnelles obligeant les diffĂ©rents tissus Ă  s’adapter tout en s’ajustant, tout au long de la croissance et au stade adulte, Ă  un certain niveau de performance fonctionnelle. Ces diffĂ©rentes interactions dĂ©veloppementales rĂ©pondent Ă  plusieurs facteurs forçants tels que les processus molĂ©culaires, gĂ©nĂ©tiques et cellulaires mais aussi l’environnement. Ce dernier va jouer sur ces interactions, mais de maniĂšre diffĂ©rente entre les phases prĂ©natale et postnatale, car l’environnement gestationnel et l’environnement Ă  la naissance sont diffĂ©rents. Pour tester les interactions entre l’organisme en dĂ©veloppement et son environnement et les consĂ©quences potentielles sur l’évolution, les Rodentia constituent un bon exemple de grande diversitĂ© Ă  tous Ă©gards (grande variĂ©tĂ© de formes, de rĂ©gimes alimentaires, de comportements et d’écologie) et donc un groupe d’étude de choix. Il s’agit d’un ordre de mammifĂšres trĂšs diversifiĂ© et disparate, dans lequel des changements peuvent ĂȘtre observĂ©s Ă  grande Ă©chelle. En outre, ce groupe comprend plusieurs organismes modĂšles qui peuvent ĂȘtre facilement Ă©levĂ©s en laboratoire, afin de tester les effets de diverses sources de variation grĂące Ă  des protocoles expĂ©rimentaux prĂ©cis. Le complexe craniofacial est une structure hautement intĂ©grĂ©e, complexe sur le plan architectural, car il est composĂ© de nombreux Ă©lĂ©ments squelettiques, et sur le plan fonctionnel, car il participe Ă  diverses tĂąches essentielles pour l’organisme. En mĂȘme temps, et de façon quelque peu paradoxale, cet ensemble est trĂšs Ă©volvable et prĂ©sente une grande diversitĂ© de formes. La base de la variation de la forme craniofaciale et son contrĂŽle sont autant liĂ©s aux effets additifs des gĂšnes qu’à leurs interactions Ă©pigĂ©nĂ©tiques et contextuelles au cours du dĂ©veloppement. Ces interactions Ă©pigĂ©nĂ©tiques pendant la croissance vont rĂ©pondre aux stimuli mĂ©caniques et autres, entre les centres d’ossification, les tissus et les organes qui composent la tĂȘte. En particulier, ces interactions contrĂŽlent la spatialisation et l’intensitĂ© du remodelage osseux en rĂ©ponse aux contraintes subies par les autres tissus. Elles vont ainsi compenser et coordonner la croissance des diffĂ©rents tissus et organes afin d’acquĂ©rir et/ou de maintenir certaines fonctions, comme l’occlusion entre les mĂąchoires supĂ©rieure et infĂ©rieure. Ces interactions Ă©pigĂ©nĂ©tiques sont donc essentielles au dĂ©veloppement normal du squelette en gĂ©nĂ©ral et du crĂąne en particulier. En rĂ©pondant aux changements de forces et de mouvements, elles seront un moteur potentiel de changements microĂ©volutifs (et donc macroĂ©volutifs) au niveau morphologique favorisant des directions adaptatives de variation et gĂ©nĂ©rant de nouvelles covariations fonctionnelles entre les traits. MalgrĂ© ce rĂŽle central, l’importance de ces interactions dans l’expression des diffĂ©rences interspĂ©cifiques et Ă  plus long terme dans la dynamique des clades reste mal comprise. L’analyse du rythme d’acquisition de la disparitĂ© chez l’adulte au cours de l’ontogenĂšse est un Ă©lĂ©ment clĂ© pour comprendre le remplissage diffĂ©rentiel de l’espace des formes par les clades. Ce projet a visĂ© Ă  Ă©tudier I) la mise en place de la disparitĂ© craniofaciale chez les rongeurs au cours du dĂ©veloppement Ă  Ă©chelle macroĂ©volutive, puis Ă  une Ă©chelle taxonomique plus fine ; et II) d’évaluer l’importance des processus Ă©pigĂ©nĂ©tiques lors de cette croissance postnatale.Understanding developmental mechanisms in evolution is crucial to apprehend the diversification of organismal forms. In mammals, changes occur during all development phases (prenatal and postnatal). Postnatal growth plays an essential role in the acquisition of the adult shape. During this period, the craniofacial complex undergoes many changes in functional constraint forcing the different tissue to accommodate while adjusting, along the growth and at the adult stage, to a certain level of functional performance. These different developmental interactions respond to several influencing factors such as molecular, genetic and cellular processes but also the environment. The latter will play on these interactions, but in different ways between the prenatal and postnatal phases, as gestational environment and environment at birth are different. For testing the interactions between the developing organism and its environment and the potential evolutionary consequences, Rodentia is a good example of broad diversity in all aspects (wide variety of forms, in diets, behavior and ecology) and thus a study group of choice. It is a very diverse and disparate mammal order, in which changes can be observed on a large scale. In addition, it includes model organisms that can be easily reared in laboratory following a precise experimental configuration to test the effects of diverse sources of variation. The craniofacial complex is a highly integrated structure, architecturally complex, as it is composed of many skeletal elements, and functionally, as it is involved in various tasks essential to the organism. At the same time, and somewhat paradoxically, this unit is highly scalable and presents a great diversity of forms. The basis of craniofacial shape variation and its control are as much, related to the additive effects of genes as to their epigenetic and context-specific interactions during development. These epigenetic interactions during growth will respond to mechanical and other stimuli between the ossification centers, the tissues and organs making up the head. In particular, these interactions control the spatialization and intensity of bone remodeling in response to other tissue strain. They will thus compensate and coordinate the growth of the different tissues and organs in order to acquire and/or maintain certain functions, such as the occlusion between the upper and lower jaws. These epigenetic interactions are thus essential to the normal development of the skeleton in general and the skull in particular. By responding to changes in forces and movements, they will be a potential driver of microevolutionary changes (and thus macroevolutionary changes) at the morphological level favoring adaptive directions of variation and generating new functional covariations between traits. Despite this central role, the importance of these interactions in the expression of inter-specific differences and in the longer term in the dynamics of clades remains poorly understood. Analysis of the tempo of adult disparity acquisition during ontogeny is a key element in understanding the differential filling of the shape space by clades. This project aimed I) at studying the establishment of craniofacial disparity in rodents during development on a macroevolutionary scale and then on a finer taxonomic scale; and II) at estimating the importance of the epigenetic processes during this postnatal growth

    Postnatal development and evolution of the rodents' craniofacial complex

    No full text
    Understanding developmental mechanisms in evolution is crucial to apprehend the diversification of organismal forms. In mammals, changes occur during all development phases (prenatal and postnatal). Postnatal growth plays an essential role in the acquisition of the adult shape. During this period, the craniofacial complex undergoes many changes in functional constraint forcing the different tissue to accommodate while adjusting, along the growth and at the adult stage, to a certain level of functional performance. These different developmental interactions respond to several influencing factors such as molecular, genetic and cellular processes but also the environment. The latter will play on these interactions, but in different ways between the prenatal and postnatal phases, as gestational environment and environment at birth are different. For testing the interactions between the developing organism and its environment and the potential evolutionary consequences, Rodentia is a good example of broad diversity in all aspects (wide variety of forms, in diets, behavior and ecology) and thus a study group of choice. It is a very diverse and disparate mammal order, in which changes can be observed on a large scale. In addition, it includes model organisms that can be easily reared in laboratory following a precise experimental configuration to test the effects of diverse sources of variation. The craniofacial complex is a highly integrated structure, architecturally complex, as it is composed of many skeletal elements, and functionally, as it is involved in various tasks essential to the organism. At the same time, and somewhat paradoxically, this unit is highly scalable and presents a great diversity of forms. The basis of craniofacial shape variation and its control are as much, related to the additive effects of genes as to their epigenetic and context-specific interactions during development. These epigenetic interactions during growth will respond to mechanical and other stimuli between the ossification centers, the tissues and organs making up the head. In particular, these interactions control the spatialization and intensity of bone remodeling in response to other tissue strain. They will thus compensate and coordinate the growth of the different tissues and organs in order to acquire and/or maintain certain functions, such as the occlusion between the upper and lower jaws. These epigenetic interactions are thus essential to the normal development of the skeleton in general and the skull in particular. By responding to changes in forces and movements, they will be a potential driver of microevolutionary changes (and thus macroevolutionary changes) at the morphological level favoring adaptive directions of variation and generating new functional covariations between traits. Despite this central role, the importance of these interactions in the expression of inter-specific differences and in the longer term in the dynamics of clades remains poorly understood. Analysis of the tempo of adult disparity acquisition during ontogeny is a key element in understanding the differential filling of the shape space by clades. This project aimed I) at studying the establishment of craniofacial disparity in rodents during development on a macroevolutionary scale and then on a finer taxonomic scale; and II) at estimating the importance of the epigenetic processes during this postnatal growth.La comprĂ©hension des mĂ©canismes de dĂ©veloppement dans l’évolution est cruciale pour apprĂ©hender la diversification des organismes. Chez les mammifĂšres, des changements se produisent tout au long du dĂ©veloppement (prĂ©natal et postnatal). La croissance postnatale joue un rĂŽle essentiel dans l’acquisition de la forme adulte. Durant cette pĂ©riode, le complexe craniofacial subit de nombreux changements de contraintes fonctionnelles obligeant les diffĂ©rents tissus Ă  s’adapter tout en s’ajustant, tout au long de la croissance et au stade adulte, Ă  un certain niveau de performance fonctionnelle. Ces diffĂ©rentes interactions dĂ©veloppementales rĂ©pondent Ă  plusieurs facteurs forçants tels que les processus molĂ©culaires, gĂ©nĂ©tiques et cellulaires mais aussi l’environnement. Ce dernier va jouer sur ces interactions, mais de maniĂšre diffĂ©rente entre les phases prĂ©natale et postnatale, car l’environnement gestationnel et l’environnement Ă  la naissance sont diffĂ©rents. Pour tester les interactions entre l’organisme en dĂ©veloppement et son environnement et les consĂ©quences potentielles sur l’évolution, les Rodentia constituent un bon exemple de grande diversitĂ© Ă  tous Ă©gards (grande variĂ©tĂ© de formes, de rĂ©gimes alimentaires, de comportements et d’écologie) et donc un groupe d’étude de choix. Il s’agit d’un ordre de mammifĂšres trĂšs diversifiĂ© et disparate, dans lequel des changements peuvent ĂȘtre observĂ©s Ă  grande Ă©chelle. En outre, ce groupe comprend plusieurs organismes modĂšles qui peuvent ĂȘtre facilement Ă©levĂ©s en laboratoire, afin de tester les effets de diverses sources de variation grĂące Ă  des protocoles expĂ©rimentaux prĂ©cis. Le complexe craniofacial est une structure hautement intĂ©grĂ©e, complexe sur le plan architectural, car il est composĂ© de nombreux Ă©lĂ©ments squelettiques, et sur le plan fonctionnel, car il participe Ă  diverses tĂąches essentielles pour l’organisme. En mĂȘme temps, et de façon quelque peu paradoxale, cet ensemble est trĂšs Ă©volvable et prĂ©sente une grande diversitĂ© de formes. La base de la variation de la forme craniofaciale et son contrĂŽle sont autant liĂ©s aux effets additifs des gĂšnes qu’à leurs interactions Ă©pigĂ©nĂ©tiques et contextuelles au cours du dĂ©veloppement. Ces interactions Ă©pigĂ©nĂ©tiques pendant la croissance vont rĂ©pondre aux stimuli mĂ©caniques et autres, entre les centres d’ossification, les tissus et les organes qui composent la tĂȘte. En particulier, ces interactions contrĂŽlent la spatialisation et l’intensitĂ© du remodelage osseux en rĂ©ponse aux contraintes subies par les autres tissus. Elles vont ainsi compenser et coordonner la croissance des diffĂ©rents tissus et organes afin d’acquĂ©rir et/ou de maintenir certaines fonctions, comme l’occlusion entre les mĂąchoires supĂ©rieure et infĂ©rieure. Ces interactions Ă©pigĂ©nĂ©tiques sont donc essentielles au dĂ©veloppement normal du squelette en gĂ©nĂ©ral et du crĂąne en particulier. En rĂ©pondant aux changements de forces et de mouvements, elles seront un moteur potentiel de changements microĂ©volutifs (et donc macroĂ©volutifs) au niveau morphologique favorisant des directions adaptatives de variation et gĂ©nĂ©rant de nouvelles covariations fonctionnelles entre les traits. MalgrĂ© ce rĂŽle central, l’importance de ces interactions dans l’expression des diffĂ©rences interspĂ©cifiques et Ă  plus long terme dans la dynamique des clades reste mal comprise. L’analyse du rythme d’acquisition de la disparitĂ© chez l’adulte au cours de l’ontogenĂšse est un Ă©lĂ©ment clĂ© pour comprendre le remplissage diffĂ©rentiel de l’espace des formes par les clades. Ce projet a visĂ© Ă  Ă©tudier I) la mise en place de la disparitĂ© craniofaciale chez les rongeurs au cours du dĂ©veloppement Ă  Ă©chelle macroĂ©volutive, puis Ă  une Ă©chelle taxonomique plus fine ; et II) d’évaluer l’importance des processus Ă©pigĂ©nĂ©tiques lors de cette croissance postnatale

    Supplementary Data 5

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    ‘Allcompat’ summary tree formatted for FigTree

    Supplementary data 2

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    List of the modifications to the matrix of Borths & Stevens (2017

    Commonalities and evolutionary divergences of mandible shape ontogenies in rodents.

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    16 pagesInternational audienceIn mammals, significant changes take place during postnatal growth, linked to changes in diet (from sucking to gnawing). During this period, mandible development is highly interconnected with muscle growth and the epigenetic interactions between muscle and bone control the spatialization of bone formation and remodelling in response to biomechanical strain. This mechanism contributes to postnatal developmental plasticity and may have influenced the course of evolutionary divergences between species and clades. We sought to model postnatal changes at a macroevolutionary scale by analysing ontogenetic trajectories of mandible shape across 16 species belonging mainly to two suborders of Rodents, Myomorpha and Hystricomorpha, which differ in muscle attachments, tooth growth and life-history traits. Myomorpha species present a much stronger magnitude of changes over a shorter growth period. Among Hystricomorpha, part of the observed adult shape is set up prenatally, and most postnatal trajectories are genus-specific, which agrees with nonlinear developmental trajectories over longer gestational periods. Beside divergence at large scale, we find some collinearities between evolutionary and developmental trajectories. A common developmental trend was also observed, leading to enlargement of the masseter fossa during postnatal growth. The tooth growth, especially hypselodonty, seems to be a major driver of divergences of postnatal trajectories. These muscle- and tooth-related effects on postnatal trajectories suggest opportunities for developmental plasticity in the evolution of the mandible shape, opportunities that may have differed across Rodent clades
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