Territoires de l'expatriation française, entre légitimité politique et appropriation citoyenne

International audienceBased on a global work towards the concept of geopolitical stake adapted to the subject of French expatriation and citizenship, this paper will address the link between individuals –in their diversity and the complexity of their trajectories– and public authorities, through the analysis of the public measures set to their attention. From the development of territorial engineering abroad and citizen involvement, between belonging feelings and representations towards France in the World, these works lay upon a field investigation led in London between 2016 and 2017, in a context of both Brexit and French presidential election. In constrast to the top-down measures imposed by public authorities, we will question the citizen and private alternatives that sometimes bring a more adequate answer to the needs of concerned population , especially in the example brought by the French education system abroad.Prenant appui sur une réflexion globale autour de la notion d'enjeu géopolitique lié à l'expatriation des Français et à la citoyenneté dans le cadre de l'expatriation, cette recherche explorera le lien entre les individus, dans leur diversité et la complexité de leurs parcours, et les pouvoirs publics, par le biais des mesures politiques mises en place à leur attention. Entre développement de l'ingénierie territoriale hors des frontières françaises et implication citoyenne, entre sentiments d'appartenance et représentations de la France dans le monde, ces travaux reposent sur une enquête de terrain menée entre 2016 et 2017 à Londres, dans un contexte post-Brexit et pré-électoral en France. En miroir des mesures top-down imposées par les pouvoirs publics, nous examinerons les alternatives citoyennes et privées qui apportent une réponse parfois plus adéquate aux besoins de la population, particulièrement dans l'exemple de l'enseignement français

La réduction des dents humaines à la transition Pléistocène-Holocène dans le sud-ouest de la France : réévaluation et apports de l’analyse de la structure interne par imagerie 3D

Une réduction de la taille des dents humaines et une simplification de leur forme ont été observées en Europe et débattues en lien avec des changements culturels et environnementaux de la fin du Pléistocène et du début de l’Holocène. Entre autres facteurs, les techniques de cuisson ou la pression démographique ont été proposées comme causes de ces modifications biologiques. Cependant, ces modèles sont toujours débattus et les mécanismes qui ont contribué à la réduction des couronnes ne sont pas entièrement compris à ce jour. Grâce à de nouvelles découvertes et la révision des contextes chronologiques et archéologiques de certains gisements du sud-ouest de la France, une réévaluation la nature des variations des dimensions dentaires a été effectuée pour les individus datés du Magdalénien supérieur, de l’Azilien et du Mésolithique ancien. Des acquisitions microtomographiques d’une partie de l’échantillon ont été réalisées afin de caractériser de manière non invasive la structure interne des dents (épaisseur de l’émail, proportions des tissus dentaires). Si une réduction globale des dimensions dentaires est constatée pour tous les types de dents, elle est plus marquée entre l’Azilien et le Mésolithique ancien. Cette réduction est principalement liée aux changements de volume et d’épaisseur de l’émail, paramètre plastique et écosensible témoignant de variations dans la biomécanique de la mastication. Ces résultats soulignent l’impact des changements environnementaux et culturels du début de l’Holocène. Une révision des modèles impliqués dans ce phénomène de réduction dentaire est proposée. Ainsi, cette approche intégrée, combinant les aspects externe et interne des dents, a permis de dégager des facteurs potentiellement responsables de la variation dentaire observée à la transition Pléistocène-Holocène

Microevolution of outer and inner structures of upper molars in Late Pleistocene and Early Holocene humans

In this study, we investigate outer and inner variations of upper second molars (UM2) for Late Pleistocene and Early Holocene modern humans, at a key-period in our evolutionary history associated with major sociocultural, economic and environmental changes. Non-metric traits have been recorded on 89 UM2 of 66 Upper Paleolithic, Mesolithic and Neolithic individuals, and 40 UM2 have been microscanned to assess variations in enamel thickness (ET) distribution and enamel-dentine junction (EDJ) shape. Major changes are found between Mesolithic and Neolithic periods: a decrease of the metacone expression combined with an increase of the hypocone development; an increase of the heterogeneity of ET distribution between lingual and buccal cusps; and an increase of the development of the dentine horn tips corresponding to the hypocone and, to a lesser extent, to the metacone. These morphological modifications could be linked to the masticatory functional changes associated with the transition to agriculture

Évolution dentaire dans les populations humaines de la fin du Pléistocène et du début de l’Holocène (19000 – 5500 cal. BP) : une approche intégrée des structures externe et interne des couronnes pour le Bassin aquitain et ses marges / Dental evolution in Late Pleistocene and Early Holocene human populations (19000 – 5500 cal. BP) : a whole crown perspective in the Aquitaine Basin, southwest France, and its margins

Since the Late Pleistocene, a reduction in size and a morphological simplification of human teeth have been observed and arguably linked to cultural and environmental changes. Following new discoveries along with the revision of key archaeological contexts, a re-assessment of the nature of crown variations on more than 1900 teeth is proposed for 176 Late Paleolithic, Mesolithic and Early Neolithic individuals from the Aquitaine Basin and its margins. In particular, a non-invasive assessment of internal tooth structure variability (enamel thickness, dental tissue proportions, enamel-dentine junction morphology) has been performed using 3D imaging methods (microtomography) and geometric morphometrics in order to characterize and interpret dental evolution from a whole crown perspective. Results from the morphometric analyses show a discontinuity between Late Pleistocene and Early Holocene populations. External dimensions, enamel thicknesses and tissue proportions are reduced in Mesolithic individuals compared to those of the Late Paleolithic, while major differences are observed in occlusal wear patterns and enamel distribution between Mesolithic and Early Neolithic samples. These data suggest that environmentally-driven modifications during the Early Holocene had a major impact on dental reduction in human populations and that Neolithic cultural changes had mostly affected enamel distribution. Finally, a correlation between occlusal wear pattern and enamel thickness distribution is observed and associated with dietary changes. In particular, enamel thickness may have rapidly evolved as a selective response to functional changes in masticatory biomechanics

3D models related to the publication: Internal tooth structure and burial practices: insights into the Neolithic necropolis of Gurgy (France, 5100-4000 cal. BC)

The present 3D Dataset contains the 3D models of external and internal aspects of human upper permanent second molars from the Neolithic necropolis analyzed in the following publication: Le Luyer M., Coquerelle M., Rottier S., Bayle P.: Internal tooth structure and burial practices: insights into the Neolithic necropolis of Gurgy (France, 5100-4000 cal. BC)

Altérations taphonomiques et micro-usures dentaires : impact sur la caractérisation des régimes alimentaires

L’étude de la micro-usure dentaire participe à la reconstruction des comportements alimentaires des populations du passé, humaines et animales. En contexte archéologique et paléontologique, les processus taphonomiques peuvent influencer la qualité des surfaces dentaires et entraîner la réduction du nombre d’échantillons observables. Ceci est particulièrement notable dans notre corpus de 19 molaires humaines Cerny (Néolithique, Bassin parisien), où 7 dents présentent des altérations réparties ..

Is the deciduous/permanent molar enamel thickness ratio a taxon-specific indicator in extant and extinct hominids?

In Primates, enamel thickness variation stems from an evolutionary interplay between functional/adaptive constraints (ecology) and the strict control mechanisms of the morphogenetic program. Most studies on primate enamel thickness have primarily considered the permanent teeth, while the extent of covariation in tooth enamel thickness distribution between deciduous and permanent counterparts remains poorly investigated. In this test study on nine extant and fossil hominids we investigated the degree of covariation in enamel proportions between 25 pairs of mandibular dm2 and M1 by a so-called “lateral enamel thickness diphyodontic index”. The results did not provide an unambiguous picture, but rather suggest complex patterns likely resulting from the influence of many interactive factors. Future research should test the congruence of the “diphyodontic signal” between the anterior and the postcanine dentition, as well as between enamel and the enamel-dentine junction topography

Methodological implications of intra- and inter-facet microwear texture variation for human childhood paleo-dietary reconstruction: Insights from the deciduous molars of extant and medieval children from France

The present study concerns occlusal dental microwear texture variation on the deciduous molars of children. A description and evaluation of microwear texture variation within facet 9 and a comparison of microwear textures between grinding facets 9 and 11 are presented. The relationship between wear facet surface area and intra-facet microwear texture variability is evaluated. The sample is composed of naturally-exfoliated, taphonomy-free deciduous second molars from twelve extant children and four archaeologically-derived medieval children (for a total of 51 surface measurements). Dental microwear texture analysis (DMTA) was performed using a confocal microscope and scale-sensitive fractal analysis (SSFA) at three standardized locations on facet 9, and one location on facet 11. Facet shape was visually assessed and scored using a headset magnifier (3×) and composite images (20× confocal microscopy). Individuals were assigned to two groups based on a qualitative assessment of facet surface area. Microwear texture variability within facet 9 was high relative to the variability of microwear textures between individuals. No significant inter-facet variation between facets 9 and 11 was detected. No clear differences in microwear and variabilities within facet 9 were found between individuals assigned to small and large facet groups. Our study shows the existence of important intra-facet microwear variation in a sample of children. Intra-facet microwear variation can affect the ability of DMTA to distinguish between diets in contexts with small sample sizes and subtle differences in diet – such as those characterizing dietary transitions in children. Results also suggest non-dietary factors may influence microwear formation during dental exfoliation. A better understanding of intra-facet microwear variation, and when and how to account for it, can improve the application of occlusal DMTA in similar contexts