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Faire la paix avec le vivant: une perspective juridico-anthropologique de la justice transitionnelle
No full textInternational audienceArmed conflicts have significant environmental consequences: destruction of places, soil and water contamination, and population displacement due to com petition for natural resources. These impacts are experienced differently by var ious social groups. In non-Western cultures with a close relationship to the non human, wars disrupt not only human social structures but also socio-ecological relations. Our analysis explores the socio-ecological implications of recognizing non-human living beings as victims of conflict to support a transition toward peace. Through case studies in Colombia and East Timor, combining legal anal ysis and field research, we rethink the notions of reparation and reconciliation. Juridico-anthropological analyses demonstrate the first steps toward conceiving law as a vector for rethinking the transition from armed conflicts to peace based on the concept of ecological solidarity and a notion of transitional justice rooted in the repair of the eco-social fabric.Les conflits armés entraînent des conséquences environnementales importantes: destruction des lieux, contamination des sols et de l’eau, ou encore déplacements de populations liés à la compétition pour des ressources naturelles. Ces impacts sont vécus différemment selon les groupes sociaux. Dans les cultures non occidentales ayant une relation étroite avec le non-humain, les guerres perturbent non seulement les structures sociales humaines, mais aussi les relations socio écologiques. Notre analyse explore les implications socio-écologiques de la re connaissance du vivant non-humain comme victime des conflits, en vue d’une transition vers la paix. À travers des études de cas en Colombie et au Timor Oriental, combinant analyses juridiques et recherches de terrain, nous repensons les notions de réparation et de réconciliation. Les analyses juridico-anthropologiques font la preuve des premiers pas vers une manière de concevoir le droit comme vecteur pour repenser la transition des conflits armés vers la paix à partir du concept de solidarité écologique, vers une notion de justice transitionnelle qui a comme base la réparation du tissu éco-social.I conflitti armati comportano importanti conseguenze ambientali: distruzione dei luoghi, contaminazione del suolo e dell’acqua, o anche spostamenti di popo lazioni legati alla competizione per le risorse naturali. Questi impatti vengono vissuti in modo diverso a seconda dei gruppi sociali. Nelle culture non occiden tali, che hanno un rapporto stretto con il non-umano, le guerre sconvolgono non solo le strutture sociali umane, ma anche le relazioni socio-ecologiche. La nostra analisi esplora le implicazioni socio-ecologiche del riconoscimento degli esseri viventi non umani come vittime dei conflitti, in vista di una transizione verso la pace. Attraverso lo studio di casi in Colombia e a Timor Est, che combinano analisi giuridiche e ricerche sul campo, ripensiamo le nozioni di riparazione e riconciliazione. Le analisi giuridico-antropologiche dimostrano i primi passi verso un modo di concepire il diritto come strumento per ripensare la transizione dai conflitti armati alla pace, a partire dal concetto di solidarietà ecologica, verso una nozione di giustizia transizionale che abbia come base la riparazione del tessuto eco-sociale
Diadromie, dispersion et histoire évolutive du genre Stenogobius dans les systèmes insulaires tropicaux Indopacifique
No full textTropical insular rivers of the Indo-Pacific host a unique and fragile aquatic biodiversity mainly represented by amphidromous freshwater species; they live in rivers but undergo a marine larval phase, important in terms of dispersal and colonisation of these fragmented habitats. These ecosystems, originally devoid of any freshwater fauna, have mostly been colonised by Gobiiformes, including the genus Stenogobius. This thesis presents an integrative analysis (morphology, genetics, otolithometry) of Stenogobius across the Indo-Pacific region. The first component focuses on a taxonomic revision the genus, revealing the presence of a widely distributed species, Stenogobius genivittatus, found from South Africa to Hawaii three endemic species at the Indo-Pacific barrier and 15 previously valid species were placed in synonymy. The second component examines life history traits related to amphidromy, in particular the duration of the pelagic larval phase, estimated by otolith microstructural analysis for S. genivittatus. Finally, the population structure of S. genivittatus was investigated to discuss the dispersal capacity of the species and the impact of past and present barriers on the species' distribution. The results presented highlight the central role of amphidromous life cycles in the colonization processes and in the maintenance of the connectivity between populations. However, these species are highly vulnerable to anthropogenic pressures and the conservation status of these species, if any, are Least Concern or Data Deficient. This work improves greatly the knowledge on the Stenogobius genus, with a revised taxonomy, which is compulsory for the implementation of future conservation and/or management measures.Les rivières insulaires tropicales de l'Indo-Pacifique abritent une biodiversité aquatique unique et fragile, principalement constituée d'espèces dulçaquicoles amphidromes. Celles-ci vivent en rivière mais traversent une phase larvaire marine, essentielle pour leur dispersion et la colonisation de ces habitats fragmentés. Ces écosystèmes, à l'origine dépourvus de toute faune dulçaquicole, ont majoritairement été colonisés par des Gobiiformes, notamment du genre Stenogobius. Cette thèse présente une analyse intégrative (morphologie, génétique, otolithométrie) du genre Stenogobius à l'échelle de l'Indo-Pacifique. La première partie porte sur une révision taxonomique du genre, révélant la présence d'une espèce largement répartie, Stenogobius genivittatus, présente de l'Afrique du Sud à Hawaï, ainsi que de trois espèces endémiques situées au niveau de la barrière Indo-Pacifique. Quinze espèces auparavant valides ont été mises en synonymie. La seconde partie s'intéresse aux traits d'histoire de vie liés à l'amphidromie, notamment la durée de la phase larvaire pélagique, estimée par l'analyse microstructurale des otolithes chez S. genivittatus. Enfin, la structure génétique des populations de S. genivittatus a été étudiée afin de discuter de sa capacité de dispersion et de l'impact des barrières passées et actuelles sur sa distribution. Les résultats présentés soulignent le rôle central du cycle de vie amphidrome dans les processus de colonisation et le maintien de la connectivité entre les populations. Toutefois, ces espèces sont particulièrement vulnérables aux pressions anthropiques, et leur statut de conservation, lorsqu'il existe, est classé au mieux en « Préoccupation mineure » ou « Données insuffisantes ». Ce travail apporte des connaissances majeures sur le genre Stenogobius, avec une taxonomie révisée, indispensable à la mise en œuvre de futures mesures de conservation et/ou de gestion
Spontaneous Initiation and Evolution of Polygonal Fault Systems During the Early Burial of Sediments in 3D Numerical Models
No full textInternational audiencePolygonal Fault Systems (PFS) or networks were generated in 3D finite-difference models within the upper (active) layer of two-layer model. The driving force of this process results from a progressive diagenetically induced volumetric contraction (porosity reduction) of the active layer during its burial. This contraction causes extensional strains, reduces horizontal compressive stresses, and increases deviatoric stresses, leading to elastoplastic yielding and strain-softening of the material in this layer. At a certain point, the initially homogeneous material loses stability resulting in deformation bifurcation and localization within narrow deformation bands (incipient faults). The material undergoes progressive failure within the bands, accompanied by the accumulation of the normal-sense displacement along the faults and the evolution of the fault system, with some faults dying and others forming. The fault architecture characterized in the models by depth-dependent fault density and pattern, is remarkably similar to the natural PFS, both buried and exhumed. The fault spacing (S) in the models scales with the active layer thickness (T) and increases as shear coupling (τ0) between the active and substratum layers decreases. The maximum throw δ along the faults linearly scales with T and increases with the volume or porosity reduction Δϕ. Under the chosen model parameters, the typical δ/T ratio of 0.045 for natural PFS, was obtained in the models for Δϕ ≈ 7%. However, a discrepancy exists between the location (depth) of the δ maximum in the model and nature, which is discussed in the paper and indicates avenues for further modeling development
Étude multi-échelle de la géodynamique et des minéralisations à éléments critiques dans la Ceinture Pyriteuse Ibérique, Portugal
No full textInternational audienc
In good form: morphological adaptations to burrowing lifestyles in cockroaches (Dictyoptera: Blattodea)
No full textInternational audience1. Investigating forms specialized for their ecology (i.e. ecomorphs) is a major theme in ecology and evolution. Among remarkable ecomorphs, those associated to fossorial habits have received increasing attention in vertebrates, but less so in invertebrates. Here, we focus on cockroaches, insects whose burrowing ecomorphs have long been observed but never formally investigated at a large taxonomic scale. 2. Our goal is to characterize different cockroach ecomorphs, with a particular focus on fossorial organisms in the broadest sense, i.e., including cockroaches digging galleries and feeding in deadwood. The study of these wood-eating species is particularly important because of the role of this diet in the evolution of eusociality in Blattodea (i.e. cockroaches and termites). 3. We used two sets of morphological data while taking into account the phylogenetic relationships of 62 species of cockroaches, sampled from nine families and covering three fossorial (hollow trunk, sand, dead wood) and two non-fossorial microhabitats (litter and under bark). The first set of data corresponded to linear measurements for 13 morphological traits, while the second set comprised 3D models of pronotums obtained by photogrammetry and microtomography and analysed by geometric morphometrics. To account for shared ancestry between species, phylogenetic comparative analyses were then carried out, including predictive analyses for six species whose microhabitat is unknown. 4. We identified morphological differences associated with different burrowing lifestyles, while highlighting the importance of considering shared ancestry. Among the most discriminating morphological traits are body length and the length of the anterior tibial spines, which distinguish species digging in deadwood from those burrowing in sand. 3D analyses of the pronotum also revealed interesting differences related to the microhabitat. Despite the ability to characterize ecomorphs from both sets of data, predictive analyses, which would be particularly valuable for fossil taxa, need further refinement