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(IF 1.64; Q3); International audience; The North West migration of long and discontinuous mud banks along the French Guiana coast has been extensively studied during the past years, in particular with a large-scale vision, which consequently has integrated morpho and hydrodynamic data. The aims of the present paper were to use intrinsic sediment properties (grain-size, mineralogy, concentration, and cohesion) to (1) highlight the sedimentary conditions during the consolidation processes from fluid deposit to vegetation development, and (2) verify the apparent homogeneously derived sedimentary facies.Two intertidal transects, Macouria and Cayenne, were compared from the coast to offshore. Their altitude averages of 1 m and 2.8 m above mean sea level, respectively, were different enough to compare the influence of the hydrodynamic impact and emersion time on their sediment properties. The latter, i.e. grain size distribution, mineralogical content, mud concentration, and shear strength (cohesion), were determined from sampled surface sediments (first cm) and along sediment cores (20–30 cm depth) from each transect. A specific X-ray technique was applied to the whole core to differentiate clearly its thin layers.On both intertidal sites, the grain size dominated by the fine silt fraction (2–20 μm) and the bulk mineralogy characterized by five major minerals (quartz, feldspars, chlorite, illite, and kaolinite) appeared homogeneous along both transects and cores. In spite of this apparent uniformity of particle size and mineralogical parameters, as well as for visual observation along the core, high precision X-rays still showed a cyclic sedimentation at a micro-scale level. This cyclicity with intercalation of fine layers was related to distinct dynamic deposits marked by both tidal processes and hydrodynamic factors (swell propagation). The cohesion and concentration results were dependent on the topography, where high topography was characterized by sediments with high cohesion and concentration values, and vice versa. A comparison between these two parameters was done to define critical limits between soft and stiff muds, as well as unvegetated and colonized muds. The favorable intrinsic sedimentary properties for consolidation and colonization were also discussed according to the field observations and bibliographic data

International audience; Photogrammetry is an old remote sensing technique that has undergone significant new developments related to the emergence of new computer vision algorithms, notably the workflow technique called Structure-from-Motion (SfM photogrammetry). These innovations facilitate the utilization of this technique by non-specialists. SfM photogrammetry now enables the production of high-resolution morphometric 3D models and derived products such as digital surface models (DSMs) and orthophotographs. We conducted three SfM-photogrammetric experiments, in French Guiana on an embayed beach in Cayenne and on a small mudflat sector of a coastal mud bank near the Sinnamary estuary, and finally in the French southern Alps on a section of the braided Bach River near Sisteron. We developed a simple field protocol based on subvertical aerial photography from a microlight aircraft at low altitude (1000 feet). We generated DSMs and the other products with user-friendly Agisoft Photoscan Professional (c) software. These SfM implementations were aimed at highlighting the subtle morphological variations characterising these features and some of the processes involved in morphological change. The DSMs were produced at a resolution of 5 to 10 cm per pixel and had a mean vertical accuracy less than 10 cm compared to the Real-Time Kinematic Differential Global Positioning System (RTK-DGPS) control points, with a maximum of 20 cm in marginal sectors near high vegetation such as trees and shrubs and on wet surfaces dose to water-filled channels or in the lower intertidal zone. Low-cost, user-friendly SfM photogrammetry offers interesting new perspectives in the fields of coastal and fluvial geomorphology requiring high-resolution topographic data. The technique combines the advantages of the reproducibility of GPS topographic surveys and the high density and accuracy of airborne LIDAR, but at very advantageous cost compared to the latter.; La photogrammétrie est une technique ancienne de télédétection qui connaît des développements significatifs liés à l’émergence des algorithmes de vision assistée par ordinateur, comme la technique nommée « Structure-from-Motion » (photogrammétrie SfM). Ces innovations facilitent l’utilisation de cette technique par des non-spécialistes. La photogrammétrie SfM permet aujourd’hui la production de modèles morphométriques haute résolution et de leurs produits dérivés comme des modèles numériques de surface (MNS) et des orthophotographies. Nous avons effectué trois expérimentations de photogrammétrie SfM : en Guyane française sur une plage de baie à Cayenne et sur un étroit secteur d’une vasière intertidale associée à un banc de vase près de l’estuaire du fleuve Sinnamary, puis dans les Alpes du Sud sur une section de la rivière en tresse du Buëch près de Sisteron. Nous avons développé un protocole de terrain accessible basé sur des photographies aériennes sub-verticales à partir d’un aéronef ultra léger motorisé (ULM) volant à basse altitude (1000 pieds). Nous avons généré les MNS et les autres produits dérivés à l’aide du logiciel Agisoft Photoscan Professional ©. Ces applications de la technique de photogrammétrie SfM ont pour objectif de souligner les variations morphologiques fines caractérisant les objets d’étude ainsi que les processus morphogènes. Les MNS ont été produits avec une résolution de 5 à 10 cm par pixel et ont une précision verticale moyenne inférieure à 10 cm au regard des points de contrôle levés à l’aide du GPS différentiel cinématique (i.e. RTK-DGPS), avec un maximum de 20 cm dans certains secteurs marginaux près de la végétation haute avec des arbustes et des arbres et sur les surfaces humides près de chenaux actifs ou dans la zone intertidale. Peu coûteuse et facile d’utilisation, la technique de photogrammétrie SfM offre des perspectives novatrices dans les champs de la géomorphologie côtière et fluviale requérant des données topographiques haute résolution. Cette technique combine les avantages de la reproductibilité des levés topographiques GPS et la haute densité et la précision des données issues du LIDAR aéroporté, mais à coût très avantageux comparé à ce dernier.

Background Palikur Amerindians live in the eastern part of French Guiana which is undergoing deep-seated changes due to the geographical and economic opening of the region. So far, Palikur’s traditional ecological knowledge is poorly documented, apart from medicinal plants. The aim of this study was to document ethnobotanical practices related to traditional construction in the region. Methods A combination of qualitative and quantitative methods was used. Thirty-nine Palikur men were interviewed in three localities (Saint-Georges de l’Oyapock, Regina and Trois-Palétuviers) between December 2013 and July 2014. Twenty-four inventories of wood species used in traditional buildings were conducted in the villages, as well as ethnobotanical walks in the neighboring forests, to complete data about usable species and to determine Linnaean names. Results After an ethnographic description of roundwood Palikur habitat, the in situ wood selection process of Palikur is precisely described. A total of 960 roundwood pieces were inventoried in situ according to Palikur taxonomy, of which 860 were beams and rafters, and 100 posts in 20 permanent and 4 temporary buildings. Twenty-seven folk species were identified. Sixty-three folk species used in construction were recorded during ethnobotanical walks. They correspond to 263 botanical species belonging to 25 families. Posts in permanent buildings were made of yawu (Minquartia guianensis) (51%) and wakap (Vouacapoua americana) (14%). Beams and rafters were made of wood from Annonaceae (79%) and Lecythidaceae (13%) families. The most frequently used species were kuukumwi priye (Oxandra asbeckii), kuukumwi seyne (Pseudoxandra cuspidata), and pukuu (Xylopia nitida and X. cayennensis). Conclusions Although the Palikur’s relationship with their habitat is undergoing significant changes, knowledge about construction wood is still very much alive in the Oyapock basin. Many people continue to construct traditional buildings alongside modern houses, using a wide array of species described here for the first time, along with the techniques used. Electronic supplementary material The online version of this article (10.1186/s13002-018-0226-7) contains supplementary material, which is available to authorized users.

The mangroves play a vital role in the ecological balance. They provide marine ecosystem resources and are involved in its stabilization and in the coastal protection. They constitute the growth areas of many species that feed marine species and particularly shrimp. We develop a standard fishery model by integrating mangroves area into the analysis. The extended model shows that mangrove plays animportant role in shrimp production and data related to it are well supported by the model. We analyze the e¤ects of mangrove on open access of the French Guiana shrimp fishery and show that mangrove is not the only factor that plays a vital role in the French Guiana shrimp fishery.

Made available in DSpace on 2018-11-26T16:22:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-03 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Ethnopharmacological relevance: This is the first intercultural report of antimalarial plants in this region. The aim of this study was to document the medicinal plants used against malaria by indigenous people in the Upper Rio Negro region and to review the literature on antimalarial activity and traditional use of the cited species. Materials and methods: Participant observation, semi-structured interviews, and ethnobotanical walks were conducted with 89 informants in five indigenous communities between April 2010 and November 2013 to obtain information on the use of medicinal plants against malaria. We reviewed academic databases for papers published in scientific journals up to January 2014 in order to find works on ethnopharmacology, ethnobotany, and antimalarial activity of the species cited. Results: Forty-six plant species belonging to 24 families are mentioned. Fabaceae (17.4%), Arecaceae (13.0%) and Euphorbiaceae (6.5%) account together for 36.9% of these species. Only seven plant species showed a relatively high consensus. Among the plant parts, barks (34.0%) and roots (28.0%) were the most widely used. Of the 46 species cited, 18 (39.1%) have already been studied for their antimalarial properties according to the literature, and 26 species (56.5%) have no laboratory essays on antimalarial activity. Conclusions: Local traditional knowledge of the use of antimalarials is still widespread in indigenous communities of the Upper Rio Negro, where 46 plants species used against malaria were recorded. Our studies highlight promising new plants for future studies: Glycidendron amazonicum, Heteropsis tenuispadix, Monopteryx uaucu, Phenakospermum guianensis, Pouteria ucuqui, Sagotia brachysepala and notably Aspidosperma schultesii, Ampelozizyphus amazonicus, Euterpe catinga, E. precatoria, Physalis angulata, Cocos nucifera and Swartzia argentea with high-use consensus. Experimental validation of these remedies may help in developing new drugs for malaria. (C) 2015 Elsevier Ireland Ltd. All rights reserved. Univ Estadual Paulista, Fac Ciencias Agron Botucatu, Dept Hort, Rua Jose Barbosa de Barros 1780, BR-18610307 Botucatu, SP, Brazil Cunuri Indigenous Community, Sao Gabriel Da Cachoeira, Amazonas, Brazil CNRS Guyane USR 3456, 2 Ave Gustave Charlery, Cayenne 97300, French Guiana Herbario EAFM, Inst Educ Ciencia & Tecnol Amazonas IFAM, Manaus, Amazonas, Brazil Univ Estadual Paulista, Fac Ciencias Agron Botucatu, Dept Hort, Rua Jose Barbosa de Barros 1780, BR-18610307 Botucatu, SP, Brazil CNPq: 555.669/2009-2 CAPES: 201062/2012-7 FAPESP: 2009/53638-7

International audience; Amazonian tree communities have already been seriously impacted by extreme natural droughts, and intense droughts are predicted to increase in frequency. However, our current knowledge of Amazonian tree species' responses to water stress remains limited, as plant trait databases include few drought tolerance traits, impeding the application and predictive power of models. Here we explored how leaf water potential at turgor loss point (π tlp), a determinant of leaf drought tolerance, varies with species life history, season, tree size and irradiance within a forest in French Guiana. First, we provided a further direct validation of a rapid method of π tlp determination based on osmometer measurements of leaf osmotic potential at full hydration for five Amazonian tree species. Next, we analysed a dataset of 131 π tlp values for a range of species, seasons, size (including saplings), and leaf exposure. We found that early-successional species had less drought-tolerant leaves than late-successional species. Species identity was the major driver of π tlp variation, whereas season, canopy tree size and leaf exposure explained little variation. Shifts in π tlp from saplings to canopy trees varied across species, and sapling leaf drought tolerance was a moderate predictor of canopy tree leaf drought tolerance. Given its low within-species variability, we propose that π tlp is a robust trait, and is useful as one index of species' drought tolerance. We also suggest that measuring this trait would considerably advance our knowledge on leaf drought tolerance in hyperdiverse communities and would thus likely shed light on the resilience of such vulnerable species-rich ecosystem.

International audience; Plant responses to natural enemies include formation of secondary metabolites acting as direct or indirect defenses. Volatile terpenes represent one of the most diverse groups of secondary metabolites. We aimed to explore evolutionary patterns of volatile terpene emission. We measured the composition of damage-induced volatile terpenes from 202 Amazonian tree species, spanning the angiosperm phylogeny. Volatile terpenes were extracted with solid-phase micro extraction and desorbed in a gas chromatography–mass spectrometry for compound identification. The chemical diversity of the terpene blend showed a strong phylogenetic signal as closely related species emitted a similar number of compounds. Closely related species also tended to have compositionally similar blends, although this relationship was weak. Meanwhile, the ability to emit a given compound showed no significant phylogenetic signal for 200 of 286 compounds, indicating a high rate of diversification in terpene synthesis and/or great variability in their expression. Three lineages (Magnoliales, Laurales, and Sapindales) showed exceptionally high rates of terpene diversification. Of the 70 compounds found in >10% of their species, 69 displayed significant correlated evolution with at least one other compound. These results provide insights into the complex evolutionary history of volatile terpenes in angiosperms, while highlighting the need for further research into this important class of compounds.

International audience; Amphibian chytridiomycosis, an emerging infectious disease caused by the fungus Batrachochytrium dendrobatidis (Bd), has been a significant driver of amphibian declines. While globally widespread, Bd had not yet been reported from within Madagascar. We document surveys conducted across the country between 2005 and 2014, showing Bd's first record in 2010. Subsequently, Bd was detected in multiple areas, with prevalence reaching up to 100%. Detection of Bd appears to be associated with mid to high elevation sites and to have a seasonal pattern, with greater detectability during the dry season. Lineage-based PCR was performed on a subset of samples. While some did not amplify with any lineage probe, when a positive signal was observed, samples were most similar to the Global Panzootic Lineage (BdGPL). These results may suggest that Bd arrived recently, but do not exclude the existence of a previously undetected endemic Bd genotype. Representatives of all native anuran families have tested Bd-positive and exposure trials confirm infection by Bd is possible. Bd's presence could pose significant threats to Madagascar's unique “megadiverse” amphibians.

International audience; In response to seasonality and spatial segregation of resources, sea turtles undertake longjourneys between their nesting sites and foraging grounds. While satellite tracking hasmade it possible to outline their migration routes, we still have little knowledge of how theyselect their foraging grounds and adapt their migration to dynamic environmental conditions.Here, we analyzed the trajectories and diving behavior of 19 adult green turtles (Cheloniamydas) during their post-nesting migration from French Guiana and Suriname to theirforaging grounds off the coast of Brazil. First Passage Time analysis was used to identifyforaging areas located off Ceará state of Brazil, where the associated habitat correspondsto favorable conditions for seagrass growth, i.e. clear and shallow waters. The dispersaland diving patterns of the turtles revealed several behavioral adaptations to the stronghydrodynamic processes induced by both the North Brazil current and the Amazon Riverplume. All green turtles migrated south-eastward after the nesting season, confirming thatthey coped with the strong counter North Brazil current by using a tight corridor close to theshore. The time spent within the Amazon plume also altered the location of their feedinghabitats as the longer individuals stayed within the plume, the sooner they initiated foraging.The green turtles performed deeper and shorter dives while crossing the mouth of the Amazon,a strategy which would help turtles avoid the most turbulent upper surface layers of theplume. These adjustments reveal the remarkable plasticity of this green turtle populationwhen reducing energy costs induced by migration.

International audience; This study examined whether the antidermatophytic activity of essential oils (EOs) can be used as an indicator for the discovery of active natural products against Leishmania amazonensis. The aerial parts of seven plants were hydro-distilled. Using broth microdilution techniques, the obtained EOs were tested against three strains of dermatophytes (Trichophyton mentagrophytes, Microsporum gypseum and Microsporum canis). To compare the EOs antifungal and antiparasitic effects, the EOs activities against axenic amastigotes of L. amazonensis were concurrently evaluated. For the most promising EOs, their antileishmanial activities against parasites infecting peritoneal macrophages of BALB/c mice were measured. The most interesting antifungal candidates were the EOs from Cymbopogon citratus, Otacanthus azureus and Protium heptaphyllum, whereas O. azureus, Piper hispidum and P. heptaphyllum EOs exhibited the lowest 50% inhibitory concentration (IC 50) values against axenic amastigotes, thus revealing a certain correspondence between both activities. The P. hispidum EO was identified as the most promising product in the results from the infected macrophages model (IC 50 : 4.7 µg/mL, safety index: 8). The most abundant compounds found in this EO were sesquiter-penes, notably curzerene and furanodiene. Eventually, the evaluation of the antidermatophytic activity of EOs appears to be an efficient method for identifying new potential drugs for the treatment of L. amazonensis.

International audience

Le territoire de la Guyane possede la particularite d’etre la seule region francaise (sans compter les Territoires d’Outre-mer) ou vivent des populations autochtones possedant encore de nombreux savoirs locaux lies a la nature avec des savoir-faire associes. Faisant de la France a la fois un utilisateur potentiel de ressources genetiques mais aussi un fournisseur de ces memes ressources et de connaissances traditionnelles associees (CTA), la Guyane francaise tient une place particuliere. Nous nous proposons ici de discuter de la mise en place de l’acces et partage des avantages (APA) en Guyane, mais surtout de montrer le positionnement des differents acteurs (politiques, scientifiques, industriels et populations locales amerindiennes) sur ce sujet. Nous insisterons plus particulierement sur l’ambiguite de l’acces aux ressources biologiques chez les peuples amerindiens de la region de l’Oyapock, dans l’est de la Guyane francaise.

De nombreux espaces frontaliers périphériques des États nationaux font l’objet, de par le monde, de politiques publiques de développement territorialisées. La frontière franco-brésilienne, entre la Guyane française, département-région d’outre-mer français, et l’Amapá, État fédéré brésilien, constitue le cas d’étude sur lequel nous examinons ici ces politiques en nous intéressant non à leur efficacité mais à leur coïncidence. Cet examen révèle un différentiel politique majeur entre France et Brésil : s’appuyant sur des logiques nationales mises en place depuis le milieu du XXe siècle, mais aussi dotées de quelques spécificités locales, elles n’ont ni la même portée géographique, ni la même nature, ni les mêmes objectifs, ni les mêmes types de pilotes.En s’appuyant prioritairement sur l’analyse des documents de politiques publiques connexes, cet article revient successivement sur celles mises en œuvre du côté français et du côté brésilien, pour aboutir à un bilan tabulaire et cartographique comparatif mettant en exergue de nets écarts et une relative ignorance mutuelle. Muitas áreas de fronteira periféricas de estados nacionais no mundo são afetadas por políticas públicas de desenvolvimento territorializadas. A fronteira franco-brasileira entre a Guiana Francesa, departamento-região ultramarino francês e o Amapá, estado federal brasileiro, é o estudo de caso em que examinamos aqui essas políticas, concentrando-se não sobre a eficiência, mas sobre a coincidência delas. Esta avaliação revela uma grande divergência política entre França e Brasil : baseadas numa lógica nacional implementada desde meados do século XX, mas também com algumas especificidades locais, elas não têm o mesmo alcance geográfico, ou a mesma natureza, ou os mesmos objetivos ou os mesmos tipos de condutores. Baseado principalmente na análise de documentos relacionados a essas políticas públicas, este artigo sucessivamente debate as implementadas do lado do francês e do lado brasileiro. Isto leva a uma avaliação tabular e cartográfica comparativa destacando diferenças claras e uma ignorância mútua. Many peripheral border areas of national States around the world are affected by public territorial policies aiming to their development. The Franco-Brazilian border between French Guiana, a French overseas department and region, and Amapá, a Brazilian federal State, is the case study in which we examine here these policies, focusing not on their efficiency, but on their coincidence. This review reveals a major political gap between France and Brazil : based on national dynamics implemented since the mid-twentieth century, but also with some local specificities, they do not have the same geographic scope, or the same nature, or the same goals or even the same kinds of drivers. Based primarily on the analysis of documents related to those public policies, this paper successively discusses those implemented on the French side and then on the Brazilian side. This leads to a comparative tabular and mapping assessment highlighting clear differences and a relative mutual ignorance.

International audience; In French Guiana, the coastal mud banks dynamics, specially the intertidal part, have been largely studied while the subtidal expansion suffers a lack of knowledge. The subtidal area requires significant study in order to understand the complete processes of mud bank migration. The aim of this short paper is to compare the mud bank migration in the subtidal area combining remote sensing data and in-situ measurement. The determination of the delimitation of the subtidal part is realized with remotely sensed data using waves attenuation as a proxy of the subtidal part location. Waves are dampened by fluid mud at proximity of the subtidal area, and are highly detectable on SPOT images. The regular bathymetric survey of the Kourou harbor channel offers a detailed situation of fluid mud arrival along the channel and so on the subtidal migration of the mud bank. Fresh mud arrival in the Kourou channel induce significant depth addition, more precisely the mud lens, important dredging effort in the navigation channel is organized to allow the passage of ships. Therefore, it is observed that the passage of mud bank contributes differently along the channel with a more pronounced arrival of fluid mud in the offshore part of the navigation channel between 2003 and 2009 while the onshore channel were silting-up by the trailing edge of the mud bank from 2010. Combining both the mud bank position from remote sensing images analyses and mud lens surveys allow the determination of the localization of a mud bank along the Kourou coast for 10years

National audience; En géographie des frontières, la modélisation constitue une pratique qui n’est pas systématisée. Il s’agit d’un objet de débat au sein de la discipline, rejoignant plus largement les controverses existantes autour de sa/ses théorisation/s. Quelques auteurs se sont néanmoins risqués à proposer des « modèles » d’effets-frontière et de relations transfrontalières, pouvant être appliqués à divers cas d’étude. On peut citer les « six exemples d’effet-frontière » que proposent J.-P. Renard et P. Picouet : l’intégration de marges, l’effet de dissymétrie, l’effet de dysfonctionnement, l’effet d’abri et de transit, l’effet créateur et accumulateur, et enfin le métamorphisme de contact qui opère la création d’un système spatial transfrontalier (Renard et Picouet, 1993, p. 7). Sous forme de catalogue, plutôt que de typologie englobante, les deux auteurs proposent des schémas de synthèse modélisant des lectures de compositions territoriales pouvant exister aux frontières.

International audience; Each year from February through July, Chelonia mydas (green turtles) and Dermochelys coriacea (leatherback turtles) come to nest on Awala-Yalimapo beach. During the nesting season, the presence of gravid turtles may directly affect the general morphology of the beach by provoking sand remobilization during firstly the conception of their nest and then during the nest disguising. Digital elevation models were realized to qualify and quantify the topographic modification conducted by the macro-bioturbation effect of marine turtles. Green turtles and leatherback turtles do not provoke the same perturbation on the beach. C. mydas affect the upper part of the beach by constructing their nest. Whereas D.coriacea provoke more important impact on the lower upper-beach when they come to lay. During the covering activity leatherback tend to disturb the morphology of the beach around their nests. Morphological changes on the beach during the nesting season draw attention to the potential effect of animal on their terrestrial habitat.

Deux peuples amérindiens de langue tupi-guarani, les Teko et les Wayãpi, vivent sur le territoire de Camopi, commune de Guyane française. Dans cet article nous nous attachons à retracer la construction historique de leurs territoires actuels, en montrant quand et comment ils se les ont appropriés. Nous explicitons également comment ces territoires sont devenus une commune de la République française. Dans une deuxième partie, nous présentons comment ces peuples s’adaptent aux changements contemporains induits par l’orpaillage illégal ayant lieu sur leur territoire et par le recrû démographique sans précédent qu’ils connaissent. Enfin, après avoir montré l’échec des politiques de regroupement que l’État français leur a imposé depuis 40 ans, nous concluons sur l’importance identitaire de leurs revendications socio-culturelles et territoriales contemporaines. Dois povos indígenas de língua Tupi-Guarani, os Wayãpi e os Teko moram no território de Camopí, município da Guiana Francesa. Neste artigo tentamos traçar a construção histórica dos territórios atuais desses povos, mostrando como e quando têm apropriado. Explicamos como estes territórios tornaram-se em um município da República Francesa. Em uma segunda parte, apresentamos como essas populações se adaptaram às mudanças contemporâneas induzidas pela garimpagem ilegal ocorrendo em seu território e o crescimento demográfico sem precedentes que eles vivem. Finalmente, depois de mostrar o fracasso das políticas de reunificação que o Estado francês impôs desde 40 anos, podemos concluir sobre a importância atual da afirmação das suas reivindicações socioculturais e territoriais contemporâneas. Two peoples of Tupi-Guarani language, Teko and Wayãpi Indians, live on the territory of Camopi, French Guiana municipality. In this article we try to trace the historical construction of the present territories of these people by showing how and when they appropriate it. We explain how these territories have become a municipality of the French Republic. In a second part, we present how these people adapt to contemporary changes induced by illegal mining taking place on their territory and to an unprecedented demographic increase of theirs own peoples. Finally, after showing the failure of reunification policies that the French state has imposed since 40 years, we conclude on the importance of the identity claims for their land and their cultures.

International audience; Investigating processes and timing of differentiation of organisms is critical in the understanding of the evolutionary mechanisms involved in microevolution, speciation, and macroevolution that generated the extant biodiversity. From this perspective, the Telestes genus is of special interest: the Telestes species have a wide distribution range across Europe (from the Danubian district to Mediterranean districts) and have not been prone to translocation. Molecular data (mtDNA: 1,232 bp including the entire Cyt b gene; nuclear genome: 11 microsatellites) were gathered from 34 populations of the Telestes genus, almost encompassing the entire geographic range. Using several phylogenetic and molecular dating methods interpreted in conjunction with paleoclimatic and geomorphologic evidence, we investigated the processes and timing of differentiation of the Telestes lineages. The observed genetic structure and diversity were largely congruent between mtDNA and microsatellites. The Messinian Salinity Crisis (Late Miocene) seems to have played a major role in the speciation processes of the genus. Focusing on T. souffia, a species occurring in the Danube and Rhone drainages, we were able to point out several specific events from the Pleistocene to the Holocene that have likely driven the differentiation and the historical demography of this taxon. This study provides support for an evolutionary history of dispersal and vicariance with unprecedented resolution for any freshwater fish in this region. Citation: Dubut V, Fouquet A, Voisin A, Costedoat C, Chappaz R, et al. (2012) From Late Miocene to Holocene: Processes of Differentiation within the Telestes Genus (Actinopterygii: Cyprinidae). PLoS ONE 7(3): e34423.

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A recent paper by Kolby et al. [1], surveying for Batrachochytrium dendrobatidis (Bd) and ranavirus in Madagascar, presents results for 508 amphibian specimens and 68 water bodies sampled during a 2-month period of the 2013–14 wet season. Kolby et al. [1] did not detect Bd in any of the samples, presenting evidence that add to our understanding of Bd dynamics in Madagascar. Earlier in 2015, we published “Widespread presence of the pathogenic fungus Batrachochytrium dendrobatidis in wild amphibian communities in Madagascar” in the journal Scientific Reports [2]. We presented rigorous spatial and temporal surveillance data for 4,155 amphibians sampled across a 10-year period, and used two independent molecular diagnostics to demonstrate the occurrence of a molecular signature of Bd infection at multiple locations across the island. We focus here on solely the Bd results, which directly relate to our published study. While the conclusions of Bd’s occurrence and prevalence in Madagascar may appear to conflict between these papers, upon closer investigation the data sets actually complement each other. Our evidence for Bd’s presence and its widespread incidence is based on multi-year monitoring data carried out through the National Monitoring Program [3] and allied survey efforts, occurring in both the wet and dry season. Our data collected during the same time as Kolby et al.’s sampling (2013–14 wet season), is consistent with their recently published results [1,2] (summarized in Table 1). Therefore, Kolby et al.’s conclusion that our data “highly contradict” those reported in their study is inaccurate. In the 2013–14 wet season, we sampled 569 frogs from 8 locations, of which only 3 samples showed a positive signal for Bd. The positive samples were collected from one individual at each of three sites: Antoetra, Ranomafana, and Ankaratra. While both datasets (the sampling reported in Kolby et al. 2015 and the wet season 2013–2014 sampling reported in Bletz et al. 2015) surveyed numerous individuals and locations across the island, there are some differences in sampling locations. More specifically, one of our positive occurrences came from Antoetra, which was not surveyed by Kolby et al [1]. Two of our positives do come from locations surveyed by both groups: Ranomafana and Ankaratra; if we combine the sub-sites within these locations, the prevalence is 0.0043 and 0.0062 respectively, which falls within the prevalence confidence intervals presented in Kolby et al. [1] (Table 1). This same logic is used by Kolby et al. [1] to show the complementarity of their field survey data and Kolby’s previous work showing Bd’s presence in amphibians imported into the US from Madagascar [4]. Both datasets are consistent with the conclusion that Bd had a very low prevalence during the 2013–2014 wet season. Table 1 Summary of published Bd survey data for the 2013–2014 wet season. The low prevalence detected in the wet season may likely be explained by seasonality of Bd. Both papers discuss the possibility of seasonal patterns, where Bd prevalence decreases in the warmer, wetter season and increases in the cooler, dryer season due to climatic or so-far un-described environmental factors. This phenomenon is not unusual and several studies have noted a high degree of seasonal variation in the prevalence of Bd (e.g. [5, 6, 7, 8]). In our published study [2] we present preliminary evidence of a seasonal pattern of Bd, showing that prevalence and/or detection was greater in the dryer, cooler season (May-Oct) than the wetter, warmer season (Nov-April) [2]. This seasonal pattern we documented likely explains the lack of detection by Kolby et al. since they sampled only in the wet (and warmer) season. Kolby et al. [1] supplement their individual sampling with the analysis of filtered water from natural habitats. In this case, the lack of Bd detection might be associated with increased water flow due to increased rainfall during the wet season, which could lower the concentration of Bd zoospores to undetectable levels. Additionally, water-filters of natural water bodies have also been found to be less sensitive than direct sampling of amphibians [9,10]. To better understand seasonal variation as well as other factors such as geographic distribution and host species variation, additional sampling across wet and dry season in a uniform and standardize manner will be important. The major difference between these papers is that we draw from data collected in multiple years and seasons and from a much larger sample of amphibians with further validation using chytrid lineage-based PCR amplification, making our study more comprehensive in nature. Kolby et al. [1] surveyed for a 2-month period, which makes it difficult to make general assumptions about pathogen occurrence from such a small snap shot in time. Our data set thus allows for the conclusion of the “widespread presence of Bd” as we document repeated detections of Bd at geographically distant locations in Madagascar albeit with varying degree of prevalence among sites and seasons. We also have secondary confirmation and validation of Bd’s presence from an independent non-nuclear lineage specific qPCR designed to the Bd mtDNA locus, which is unique to our study. Kolby et al. [1] suggest that Bd in Madagascar cannot yet be described with certainty in part due to the variability of sampling and detection methods. We acknowledge ourselves that our use of various methods may confound some of our findings, such as the seasonal pattern of Bd; however, and importantly, this does not negate or question the evidence for Bd-positive samples collected from Madagascar. While the data presented by both studies indicate a low prevalence of Bd in Madagascar in 2014, we argue that the additional multi-year data we have collected strongly supports the occurrence of one or more Bd lineage(s) in the samples collected from wild Madagascar amphibians. A similar conclusion was also made by Kolby et al. [4] based on their observations of Bd in wild-caught frogs from Madagascar that were imported into the USA. Definitive and final confirmation of Bd in Madagascar awaits histopathology, isolation of a Bd culture, and/or genome sequencing. These additional analyses can clarify whether Madagascar is facing the panzootic, hypervirulent Bd-GPL or a different (possibly endemic) Bd-lineage. More importantly, our results may have serious conservation implications. We presented strong evidence that at least one lineage of Bd exists in Madagascar, with increased prevalence at some locations during the dry season. It remains to be understood if this genotype is virulent with respect to the resident anuran fauna and capable of causing population declines. Using the ‘precautionary principle’ in reacting to suspected introductions of novel emerging infectious diseases infecting wildlife [11] it is essential to initiate conservation actions. Continuing ongoing population monitoring of Madagascar's amphibians and pathogen surveillance through the NMP are therefore essential and are a priority of the national amphibian conservation strategy for the country known as ‘A Conservation Strategy for the Amphibians of Madagascar (ACSAM) [12,13]. If it is relatively hypovirulent, it gives conservationists time to engage in mitigation strategies and to plan for the possible (and likely inevitable) arrival of a virulent genotype, which could threaten the diverse, endemic frog communities.