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Territory Health: A Transdisciplinary Approach of Environmental, Plant, Animal, and Human Health Interdependencies in a Rural Landscape in France
No full textInternational audienceHealth is increasingly understood as an integrated property of human, animal, plant, and environmental systems, as articulated by the One Health and EcoHealth concepts. The Territory Health project applies these perspectives within an agricultural landscape to examine interdependencies between environmental, non-human organisms, and human health. Using in a participatory and experimental approach, the project brings together researchers, local residents, farmers, decision-makers, and NGOs to investigate the relationships between pesticide use, in situ exposure to pesticide mixtures, and health effects on non-target organisms. A key objective is to establish a "partner cohort" to examine how changes in food production, dietary practices, and the human-nature relationship shape health of the territory under study. By situating the food-biodiversity-environment-health nexus within a socioecosystem perspective, this work supports agrifood system transformations toward long-term territorial health
Sex Ratio Bias Triggers Demographic Suicide in a Dense Tortoise Population
No full textInternational audienceABSTRACT In theory, biased adult sex ratios combined with high population densities in physically coercive mating systems could trigger an extinction vortex, regardless of external factors such as predation or habitat loss. However, this has never been documented in the wild. In an exceptionally dense island population of Hermann's tortoises in Lake Prespa in North Macedonia, sexually coercive males dramatically overnumber females, inflict severe copulatory injuries and put them at risk of fatal falls from the island plateau's sheer rock faces. Harassed females are emaciated, reproduce less frequently, produce smaller clutches and have lower annual survival rates compared to females from a neighbouring mainland population. Sixteen years of capture‐recapture data reveal an ongoing extinction event and predict that the last island female will die in 2083. Paradoxically, while high population density might suggest prosperity, it can trigger population collapse under highly skewed adult sex ratio in a coercive mating system
Who’s coming home? Shorter early-life telomeres predict return to the natal colony in an Arctic seabird
No full textInternational audienceIn wild animals, the length of their telomeres, the non-coding DNA sequences protecting the ends of chromosomes, in early life has been shown to predict their performance (eg, survival, reproduction) later in life. However, literature has reported mixed relationships between telomere length (TL) and individual performance, possibly because many previous studies overlooked the effects of the resource-modulated trade-off between growth and telomere maintenance. We investigated the effects of early-life conditions, ie, sibling competition (one or two chicks) and trophic level (nitrogen isotopic values), on the TL of black-legged kittiwake (Rissa tridactyla) chicks while accounting for the growth-TL tradeoff. We also tested whether early-life TL was related to their return probability to the natal colony within six years after fledging (a proxy of survival to adulthood). Although there was no strong evidence for direct effects of the early-life conditions on TL, we found that in broods of two chicks, larger individuals tended to receive a higher-trophic-level diet and have shorter telomeres. This suggests that sibling competition might have imposed stronger resource constraints on the chicks, making them prioritize the limited resources towards growth at the expense of TL. Surprisingly, we found that chicks with shorter telomeres were more likely to return to their colony, whereas body size was not related to return probability, suggesting that TL may be a more comprehensive predictor of return probability than body size. Therefore, our study supports that early-life TL can be a predictor of later-life performance, but it should be used with caution by considering the effect of the resourceallocation trade-off with growth, which can influence the direction of prediction
Passive acoustic monitoring from profiling floats as a pathway to scalable autonomous observations of global surface wind
No full textInternational audienceAbstract. Wind forcing plays a pivotal role in driving upper-ocean physical and biogeochemical processes, yet direct wind observations remain sparse in many regions of the global ocean. While passive acoustics have been used to estimate wind speed from moored and mobile platforms, their application to profiling floats has been demonstrated only in limited cases. Here we report the first deployment of a biogeochemical profiling float equipped with a passive acoustic sensor explicitly designed for wind retrieval, aimed at detecting wind-driven surface signals from depth. The float was deployed in the northwestern Mediterranean Sea near the DYFAMED (DYnamique des Flux Atmosphériques en MEDiterranée) meteorological buoy from February to April 2025 and operated at parking depths of 500–1000 m. We demonstrate that wind speed can be successfully retrieved from subsurface ambient noise using established acoustic algorithms, with float-derived estimates showing good agreement with collocated surface observations. To evaluate scalability to remote regions, we simulate a remote deployment scenario by refitting the acoustic model of Nystuen et al. (2015) using ERA5 reanalysis as a reference for surface wind. The ERA5-based calibration performs well under moderate winds but exhibits systematic high-wind bias (≥ 10 m s−1). Finally, we apply a residual learning framework to correct these estimates using a limited subset of DYFAMED wind data, simulating conditions where only brief surface observations are available. The corrected wind time series achieved a 38.6 % reduction in RMSE, demonstrating the effectiveness of combining reanalysis with sparse in-situ calibration. This framework improves agreement with in-situ wind observations relative to reanalysis alone, supporting a scalable strategy for float-based wind monitoring in data-sparse ocean regions. Such capability has direct implications for improving estimates of air–sea exchanges, interpreting biogeochemical fluxes, and advancing climate-relevant ocean observing
Farming practices induce contrasted effects on parasitic infections in passerine birds in agricultural landscapes
No full textInternational audienceAgricultural intensification has led to landscape changes and the extensive use of synthetic pesticides. Concurrently, a significant decline in biodiversity has been observed, especially for birds that frequent farmlands, which may ultimately affect community structures by altering interspecific relationships. While the contribution of pesticides to bird declines is now widely recognised, their impacts on host-parasite interactions remain largely unexplored. Pesticides may influence the presence and abundance of parasites and/or alter the host's immune system, affecting control over pathogenic infections. We investigated, for the first time to our knowledge, the differences in wild passerines' parasite burden, caught within 10 sites mainly surrounded by conventional farming (CF) and 10 sites mainly surrounded by organic farming (OF), as these landscapes differ in pesticide use. We estimated the number of two ectoparasites (ticks, chewing lice) and two endoparasites (blood parasites Plasmodium, coccidia) in 10 bird species. Our results highlighted a strong effect of the year and bird species on parasitic infections. Nevertheless, farming practices induced contrasted effects on parasitic burdens in birds: ectoparasite burdens were lower in CF, while blood parasite burdens were higher in this environment. This suggests that both farming practices can have a positive or negative effect on avian parasitic infections, and on bird health more generally
Projet collectif de recherche - En remontant le fleuve...Paysages et sociétés du Blavet préhistorique: Rapport d’activités 2025 - Année intermédiaire de triennale 2024-2026 - N° d’autorisation : 2025-171 et 2025-248
No full textLe service départemental d’archéologie du Morbihan a proposé de mettre en place en 2020 un projet de recherche triennal portant sur la Préhistoire de la vallée du Blavet. Soutenu par l’État (DRAC Bretagne), ce projet intitulé « En remontant le fleuve… Paysages et sociétés du Blavet préhistorique » s’inscrit dans des problématiques de recherches de l’UMR 6566 et réunit des archéologues issus de différents horizons institutionnels (Conseil départemental, Ministère de la Culture, CNRS, Universités).La genèse de ce projet répond à un constat : les sites préhistoriques répertoriés « hors littoral » sont rares dans le Morbihan. Ce manque de connaissances illustre-t-il, au moins partiellement, une certaine réalité archéologique ou est-il uniquement le fait d’un biais des prospections et d’une méconnaissance des processus sédimentaires régionaux ? Le territoire sélectionné, le « corridor » du Blavet et son bassin versant constituent un secteur pertinent pour aborder cette question.La problématique principale du projet concerne la dynamique d’occupation de ce territoire au cours de la Préhistoire, en étudiant l’évolution des stratégies d’implantation et d’exploitation des ressources par les chasseurs-collecteurs, puis les premiers agriculteurs. Afin de répondre au mieux à cette problématique principale, cinq axes de travail ont été définis. Cette approche qualifiée de pluridisciplinaire, dans la perspective d’une analyse systémique, paraît la plus amène de faire progresser nos connaissances de ce secteur géographique. Le secteur s’étendant géographiquement des landes de Lanvaux jusqu’à Guerlédan au Nord du département du Morbihan, soit une zone correspondant à la moyenne vallée du Blavet, a été sélectionné pour devenir la « zone atelier » du projet. Le présent rapport expose les différentes actions réalisées durant l’année 2025. Cette année constitue la seconde année d’un nouveau cycle de recherches du projet qui se développe désormais lors d’une triennale 2024-2026. Les activités se sont organisées afin de répondre à différents objectifs parmi lesquels :- poursuivre des recherches de longue haleine à l’image des prospections pédestres qui investissent préférentiellement maintenant les communes de Pluméliau-Bieuzy, Le Sourn et Saint-Thuriau- combiner des études en technologie et en pétrologie lithique afin d’alimenter de façon complémentaire les synthèses territoriales réalisées secteurs par secteurs- développer les opérations de terrain au coeur des recherches du pôle paysage qui investit désormais le fond de vallée.Cette seconde année 2025 a permis d’une part d’atteindre les objectifs scientifiques visés, tels que relatés dans ce rapport intermédiaire et d’autre part, a aussi permis de préparer les dernières opérations de terrains prévues pour 2026, dernière année de cette triennale. Enfin, ont aussi été portées de manière affirmée différentes actions de valorisation destinées à un large public, actions de valorisation qui caractérisent aussi le PCR depuis ses débuts
Advancing cancer research via comparative oncology
No full textInternational audienceIn the ongoing battle against cancer, the natural world provides promising inspiration for designing novel therapeutic strategies. The field of comparative oncology offers a valuable source of such inspiration. By combining evolutionary biology, ecology, veterinary medicine and clinical oncology, comparative oncology aims to better understand cancer, especially by highlighting taxa that are strongly resistant or susceptible to cancer and to identify the molecular and cellular mechanisms underlying the remarkable cancer resistance of some taxa. Such studies hold profound implications for human cancer research and treatment, and increase the probability of detecting therapeutic avenues that are non-toxic to healthy cells and tissues. This Perspective underscores the importance of comparative oncology, emphasizes its relevance, and showcases recent breakthroughs in identifying natural cancer resistance mechanisms and opportunities for clinical translation. We advocate for a better integration of cancer research on non-conventional model species into oncology and we urge enhanced cooperation between clinicians and comparative oncologists to advance cancer prevention or treatment strategies
Exemplar Sampling Algorithm for Instance Incremental Learning on Imbalanced Document Datasets
No full textInternational audienceIn this study, we propose an exemplar sampling algorithm to enhance the performance of end-to-end instance incremental learning for imbalanced administrative and financial document classification. This method uses a Determinantal Point Process (DPP) to select diverse exemplars representative of the dataset. The proposed algorithm is evaluated on both private and public administrative imbalanced datasets and compared with four other sampling algorithms. On the private dataset, our method outperforms all other methods and addresses the forgetting issue in incremental learning entirely. The accuracy, mean recall, weighted precision and mean F of DPP are 98.56%, 95.12%, 98.57% and 95.14%, respectively. It surpasses static learning, which uses all documents to train at once, in terms of mean recall by 0.3% while reducing accuracy by 0.07% and weighted precision \& mean F by only 0.03%. Additionally, on the public RVL-CDIP imbalanced dataset, our sampling algorithm demonstrates superiority over the other sampling algorithms and static learning, especially in achieving the highest accuracy, mean recall and mean F of 87.99%, 87.50% and 87.54%, respectively
Entre traditions et transformations : Le rôle des femmes dans le secteur viticole
No full textInternational audienceLe secteur viti-vinicole traverse une phase de mutations profondes sous l’effet cumulé des défis environnementaux, géopolitiques et institutionnels. Dans ce contexte instable, l’étude de la place des femmes repreneuses de domaines viticoles permet de mieux comprendre les dynamiques d’adaptation, de transmission et d'innovation dans un univers historiquement marqué par des normes de genre restrictives. Mobilisant une approche sociologique et genrée, notre recherche exploratoire repose sur 17 entretiens qualitatifs menés auprès de repreneuses issues de trois régions viticoles françaises (Alsace, Cairanne, Muscadet). Elle interroge les freins et leviers qui jalonnent leur parcours, depuis la conquête de leur légitimité au sein de la famille et de la profession, jusqu’à leur capacité à introduire de nouvelles pratiques. Les résultats révèlent que les trajectoires de ces femmes s'inscrivent dans une tension permanente entre héritage et transformation : elles doivent composer avec des attentes traditionnelles tout en affirmant des stratégies d'innovation et de renouvellement. L’expérience professionnelle antérieure, la mobilisation de réseaux d’entraide féminins, et l’adoption de pratiques de gouvernance plus collaboratives apparaissent comme des facteurs clés de réussite. En mettant en lumière ces trajectoires singulières, notre étude invite à repenser les dynamiques de succession dans les entreprises familiales viticoles et souligne l'importance d'un écosystème entrepreneurial plus ouvert