HAL-EPHE's Open Archive (Ecole Pratique des Hautes Etudes
Not a member yet
89096 research outputs found
Sort by
Diversification and historical biogeography of the Himalayan toad (Duttaphrynus himalayanus)
No full textInternational audienc
A Mind Journey to the Divine Court: Translating an Early Modern Taoist Rite for Internal Petition
No full textInternational audienc
Comment Hélinand de Froidmont travaillait-il ? Découvrir ses notes grâce à des collections d’exempla cisterciennes
No full textInternational audienc
Cent ans après, à chacun son Mishima
No full textInternational audienceSeen from end to beginning, the life of Yukio Mishima seems like a destiny in which everything that happened could not have unfolded any other way. Yet it is precisely this notion of an easy fatalism that has given rise to many misunderstandings in the interpretation of his work and in the understanding of his character. On the centenary of the birth of the author of Confessions of a Mask, Thomas Garcin, a professor of Japanese Studies at the University of Paris and a profound connoisseur of the writer's legacy, paints a portrait that contradicts the clichés that have built up around Mishima. In this ‘Register’, each of us is invited to create (or recreate) our own image of him
No impact of black-eye symptom on foraging behaviour and reproductive success of Northern gannets following highly pathogenic avian influenza
No full textInternational audienceHighly Pathogenic Avian Influenza Virus (HPAIV) is currently causing major wild animal population crashes all over the world including Antarctica. Yet, there are important knowledge gaps on the implications of long-lasting symptoms for the ecology of surviving individuals and the conservation of their populations. Using GPS tracking devices and long-term demographic data, we examined the effects of HPAIV on a seabird population of Northern gannets (Morus bassanus) in the colony of Rouzic, France. One year after the HPAIV outbreak of 2022, the breeding gannet population declined by 38 % and 22.3 % of surviving breeders were zombie birds: they had darkened irises, a black-eye symptom indicative of past infection to HPAIV. Importantly, we demonstrate that black eyes were not associated with detectable differences in the foraging behaviour and habitat use of surviving breeding gannets. Compared to years prior to the outbreak, the foraging effort of breeding individuals was lower and breeding success was higher, aligning with Ashmole's halo hypothesis, which posits that smaller seabird populations face lower intra-specific competition for food in the vicinity of their breeding colony and thereby, have a reduced foraging range. Our results highlight the importance of density-dependant mechanisms in population responses to sudden mass-mortalities, but raise conservation concerns, especially for species facing cumulative threats. In the long-term, locally depleted populations may reach critical thresholds where individual abundance and productivity may not be sufficient to maintain a positive demographic growth rate, ultimately leading to local population extinctions
Sesquiterpene diversity and TPS-a gene characterization in the pelargonium genus
No full textInternational audienceSesquiterpenes are key molecules nurturing the complex and subtle base notes of pelargonium fragrances. Yet, their contribution to the essential oil olfactory profile and their biosynthesis are far from being well understood. We therefore explored sesquiterpene composition in 10 pelargonium accessions and revealed that, although lowly accumulated, their wide diversity participates to the biochemical uniqueness of each fragrance. We further investigated sesquiterpene biosynthesis thanks to a multiomic approach, integrating transcriptomic together with metabolomic data. A phylogenetic analysis of pelargonium TPS-a subfamily first revealed a total of 21 groups of orthology and denoted a strong transcriptional regulation of related enzymes. Seven sesquiterpene synthases were then wisely selected for functional characterization, both in vitro and in planta. Among them, two 6,9-guaidiene synthases were characterized for the first time in plants. Finally, we explored the role of amino acids located in the active site of sesquiterpene synthases in the enzymatic mechanism using site-directed mutagenesis. Altogether, this work highlights the great potential of the multiomic approach to predict TPS functions, but also exposes its limitations, inherent to terpene synthase's plasticity.</div
Councils, local power and social mobility at the turn of the third millennium BC
No full textInternational audienc
Citizen science contributions to soil biodiversity research and conservation: insights from European studies
No full textInternational audienceCitizen science (CS) has emerged as a valuable approach for bridging knowledge gaps in biodiversity studies by expanding spatial and temporal coverage, yet remains underused in soil biodiversity monitoring. We conducted the first Europe-wide synthesis of CS initiatives dedicated to soil biodiversity, systematically reviewing published and unpublished projects to assess their contributions and limitations. A total of 126 papers and projects were analyzed across 36 countries, with Western European countries leading in study volume. National-scale studies dominated, with urban areas being the most studied land use type. Taxonomic coverage was broad but uneven, dominated by soil macrofauna (ants, gastropods and earthworms) and fungi. Methodologies ranged from opportunistic sampling to structured surveys, reflecting diverse scientific objectives and producing data of variable quality. Citizens contributed substantially to species identification, although verification practices varied widely, from expert validation to self-reported identifications without verification. Overall, our synthesis reveals a fragmented but dynamic CS landscape that, while providing valuable contributions, remains far from realizing its full scientific potential. Strengthening the role of CS in soil biodiversity research will require greater emphasis on taxonomic accuracy, with error rates systematically assessed. Emerging image-based identification tools, including community-based identification features and automated species recognition, offer promising avenues to enhance both taxonomic accuracy and participant engagement. Equally important is fostering inclusive participation to broaden spatial coverage and co-develop conservation-relevant indicators with stakeholders. Finally, dataset interoperability and metadata standardization are essential to integrate heterogeneous initiatives and unlock the full potential of CS for researchers and soil biodiversity monitoring frameworks
Galien, Des habitudes: texte établi et traduit par V. Boudon-Millot
No full textInternational audienc
A reversed latitudinal ocean oxygen gradient in the Proterozoic
No full textInternational audienceMajor changes in the oxygenation of the atmosphere and ocean have been suggested to trigger the taxonomic diversification and ecological expansion of complex life, including animals, during the Neoproterozoic–Palaeozoic transition. However, testing this hypothesis is hampered by the paucity of quantitative constraints on the oceanic oxygen availability at that time. Here we show how the spatial pattern of I/Ca ratios in marine carbonates—a proxy for dissolved oxygen in the local upper ocean—provides a fingerprint of the oxygenation state of Earth’s surface. Spatial analyses on published I/Ca ratios spanning the past 2,000 million years show that the latitudinal gradient of oxygen concentrations in the upper ocean was reversed in the Proterozoic eon relative to the modern pattern of decreasing oxygen concentrations from the mid-latitudes to the Equator. Using an Earth system model, we identify that the Proterozoic I/Ca latitudinal pattern is associated with a biosphere-controlled distribution of oxygen in the upper ocean at a low atmospheric oxygen level, and the transition to a modern pattern in the I/Ca proxy may correspond to a threshold of around 1% of today’s atmospheric oxygen concentration