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Slippery slopes: Montane isolation and elevational shifts shape the evolution and diversity of Iberolacerta lizards
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Seasonal hazard-vulnerability patterns between drought and wildfire in New Caledonia derived from remote sensing products
No full textInternational audienceClimate change is escalating the frequency and intensity of droughts and wildfires globally. In New Caledonia, future intensification is projected, yet the seasonal and directional temporal relationships between vegetation drought and wildfire activity remain insufficiently characterized at the regional scale. This study presents a regional case study combining remote sensing and in-situ datasets spanning 2000-2024, aggregated at monthly and municipal scales, to analyse drought-fire temporal interactions in New Caledonia. The approach quantifies the temporal sequencing of interactions between vegetation condition and burned area occurrence, distinguishing periods when vegetation stress precedes fire activity (fire hazard) from periods when fire occurrence is followed by altered vegetation conditions (post-fire vulnerability and potential feedbacks). Lagged and seasonal correlation analyses were conducted using the Vegetation Health Index (VHI) as a proxy of vegetation drought and the Burned areas Anomaly Index (BAI) to characterize wildfire activity. Results reveal robust and spatially coherent correlations between vegetation drought and burned area extent, highlighting the strong association between VHI and subsequent wildfire activity. Distinct seasonal interaction patterns emerge, with vegetation condition preceding fire activity during the early dry season (August-September), while fire occurrence is followed by modified surface conditions over subsequent months (November-May), consistent with postfire ecosystem vulnerability and feedback mechanism. Marked geographic contrasts are observed, particularly between the west and east coasts. These findings improve understanding of drought-fire temporal linkages in New Caledonia and provide actionable, region-specific insights for seasonally targeted and spatially explicit wildfire risk management
A phylogenomic and morphometric reassessment of Ovulidae highlights host-related shell shape evolution
No full textInternational audienceThe egg-cowries comprise a family of specialised carnivorous caenogastropods (Ovulidae Fleming, 1828) that feed by browsing on octocorals, hexacorals and stylasterid hydrozoans. A recent phylogenetic study, employing a Sanger-based multilocus nucleotide dataset, revealed numerous instances of morphological-molecular incongruence and raised the need for a revision of the current classification. To test alternative hypotheses of ovulid classifications, we applied a phylogenomic approach relying on an Exon-capture methodology to 41 samples from 26 genera and 41 species, representative of the subfamily-and genus-level diversity. Tree reconstructions were performed using both Maximum Likelihood and Bayesian inference methods, resulting in a total of five well-supported subfamily-level clades. The genera Jenneria and Pseudocypraea formed a monophyletic clade, sister to Pedicularia, altogether here considered as forming the subfamily Pediculariinae. The monophyly of Ovulinae was upheld, incorporating Quasisimnia. Prionovolvinae as traditionally recognised proved to be a melting pot of diverse genera and species, including Ovula isibasii, challenging conventional morphology-based classifications. To further investigate morphological variation within Ovulidae, we conducted 2D geometric morphometric analyses to assess shape differences. Groups emerging from Principal Component Analysis (PCA) aligned with the traditional, morphology-based classification. The weak phylogenetic signal associated with the morphometric patterns suggested that phylogeny had only a marginal influence on the morphological evolution of this clade, in contrast to the much stronger role played by host adaptation. This phylogenetic reassessment based on robust genomic data, not only helped to refine our taxonomic framework but also underscores the power of molecular insights in investigating complex evolutionary relationships within families such as the Ovulidae. Furthermore, the morphometric multivariate analysis proved efficient in revealing patterns and addressing eco-evolutionary links
Historias del ecologismo, influencias y trayectorias en España (1950-2024)
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Monitoring tropical forests with light drones: ensuring spatial and temporal consistency in stereophotogrammetric products
No full textInternational audienceThis study benefited from an "Investissement d'Avenir" grant managed by the Agence Nationale de la Recherche (CEBA, ref. ANR-10-LABX-25-01), via project PHENOBS. We also acknowledge the support of the UE Biodiversa+ BiodivMon program (Project Coforfunc). We are thankful to Ilona Clocher, Jean-Louis Smock, Jean-Yves Goret, Florian Jeanne and Julien Engel for their help with drone data acquisition and/or processing. Access to the Paracou site and infrastructure (https://paracou.cirad.fr) was granted by CIRAD/Ecofog, and we thank Géraldine Derroire and all Phenobs project participants. We are grateful to Raphaël Pélissier for helping in the initial shaping of the Phenobs project and for his continued support
Les pouces des Néandertaliens de La Ferrassie : indices d’asymétrie et de spécialisation fonctionnelle
No full textInternational audienceLes premiers métacarpiens constituent des témoins privilégiés des comportements manuels, leur structure interne reflétant l’histoire mécanique des sollicitations auxquelles ils ont été soumis. Grâce à la plasticité du tissu osseux, ces éléments s’adaptent aux contraintes répétées au cours de la vie. L’étude de l’asymétrie bilatérale sur les premiers métacarpiens fournit ainsi des indices sur des préférences latérales et éclaire la nature des gestes techniques récurrents chez les hominines. Afin d’explorer cette question, nous avons examiné par micro-CT scans les premiers métacarpiens droits et gauches de La Ferrassie 1 et 2 (45-43 ka), comparés à un échantillon d’Homo sapiens actuels dont le profil biologique et les activités manuelles sont connus. Les analyses, menées avec le package MorphoMap sous R, permettent de caractériser finement la distribution et la rigidité de l’os cortical, en lien avec certains types d’activités manuelles.Les résultats révèlent un dimorphisme sexuel marqué : LF1 (mâle) présente une plus grande épaisseur corticale et une rigidité accrue par rapport à LF2 (femelle). De plus, une asymétrie directionnelle distincte est observée chez chaque individu : un net biais gaucher chez LF2, tandis que LF1 montre des indices compatibles avec une latéralisation droitière, bien que moins prononcés. Ces différences reflètent des sollicitations mécaniques distinctes : LF1 se rapproche des profils d’ouvriers spécialisés dans des tâches de précision, tandis que LF2 évoque un travail manuel plus intensif et répétitif.Ces observations suggèrent que les pouces des deux Néandertaliens de La Ferrassie semblent avoir été soumis à des sollicitations fonctionnelles différentes. L’étude ouvre ainsi de nouvelles perspectives sur l’articulation entre asymétrie bilatérale, contraintes fonctionnelles et comportements techniques chez les populations du Paléolithique
Cocaine use in Europe: the need for cross-sectoral collaboration between security, justice, health, and social systems
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Comparison of high resolution XRF and downhole geophysical scanning of Nussloch loess records, Germany, with field observations
No full textInternational audienceNussloch (Germany) is a distinctive site of interest, particularly as a reference sequence for Late Pleistocene European loess, because it provides a comprehensive record of millennial climate variability. A notable feature of this site is its location within an active quarry. Consequently, the stratigraphic profiles documented constitute an ephemeral record, susceptible to rapid disappearance or brief accessibility, contingent on the operational status of the quarry. In order to guarantee the maintenance of a complete record of the sequence, three separate cores were collected and labelled S1, S2, and S3. The results of core S2, which is the most complete and thoroughly examined, are presented here. A comparison is drawn with the most recent P8 profile that is currently available. XRF measurements, conducted after the cores had been opened and described, are also presented. Borehole logging was carried out in the field after core retrieval, and the resulting measurements are also presented. The findings of this study demonstrate that a high degree of correlation can be established between the records from outcrop investigations and core studies, demonstrating the importance of preserving such archives for future research
Landscapes of uncertainty: Mangrove rice farmers' perceptions of rainfall variability and climate change adaptation in three coastal regions of Guinea-Bissau, West Africa
No full textInternational audienceRainfall variability poses growing challenges to mangrove rice farming in Guinea-Bissau, threatening both local livelihoods and food security. This study investigates how farmers in the coastal regions of Cacheu, Oio, and Tombali perceive changing rainfall patterns and adapt their cropping calendars accordingly. Using a companion modelling approach, we co-designed a serious game with 45 mangrove rice farmers from 13 villages, complemented by group interviews and participant observation. The results reveal that farmers possess detailed, experience-based knowledge of rainfall variability-particularly regarding the delayed onset, mid-season dry spells, and early cessation of rains-which directly influences key agricultural decisions such as nursery establishment, transplanting, and harvesting. Through the serious game, participants collectively identified and validated four main adaptation strategies: (1) flexible adjustments to cropping systems (e.g., shifting to direct seeding in erratic years), (2) strategic use of short-and medium-cycle rice varieties, (3) enhanced water management through reinforced dykes and drainage innovations, and (4) diversification into complementary livelihood activities such as cashew cultivation and fishing. The serious game proved to be an effective tool for facilitating dialogue, sharing local knowledge, and collectively refining context-specific adaptation pathways. These findings underscore the value of integrating farmers' ecological knowledge with participatory methodologies to support resilient agricultural planning under climate uncertainty.</div
From Butler to Wakanda: Afrofuturism as Transatlantic Dialogue
No full textInternational audienceThis paper examines how twentieth-century African and African American Afrofuturist works anticipate and resonate with Ryan Coogler’s Black Panther (2018), positioning the film not as a rupture but as a crystallization of long-standing transatlantic conversations. By placing Octavia Butler’s Parable of the Sower (1993) and Wanuri Kahiu’s Pumzi (2009) in dialogue with Black Panther, I argue that Coogler synthesizes a diasporic tradition of speculative aesthetics that interrogates sovereignty, memory, and futurity across the Black Atlantic