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A multi-modal ResNet model to predict coastal fish occurrences using a seascape approach
No full textIn a context of rapidly declining biodiversity, knowing the distribution of endangered species is critical to ensure the protection of the areas they occupy. To achieve this, species distribution models (SDMs) typically use a range of variables to determine the suitability of an area to a given species, which enables scientists to produce species distribution maps.Most SDMs are statistically limited in the number of predictors they can take into account, which leads to using summary variables such as temperature yearly average or bathymetry extrema. Deep learning-based SDMs have been proposed to tackle this limitation by bringing powerful implicit feature extractors. Here, we describe a new model to advance the adaptation of such Deep-SDMs to marine environments and take advantage of the knowledge of the environmental seascape around surveyed points.We used data from the Reef Life Survey data set to predict the presence of 1,796 fish species around all of Australia, in a wide range of climates. The environmental seascape around each point was encoded as a raster image populated with 15 environmental variables, 4 human activity variables, and completed by a 10-year time series of temperature anomaly.The model performance was highly dependent on the species, with a 0.95 F1 score for the best performing species, Notolabrus parilus, but rapidly decreased, with the 100th best species having a 0.38 F1 score
Cultural Production Reveals Transitions to Sustained Human Development in both European and Non-European Societies
No full textSustained human development is often seen as a recent phenomenon, primarily linked to Europe's Industrial Revolution. This perspective has shaped much of our historical understanding, but it relies on a limited set of economic indicators with restricted temporal and geographic coverage. In this article, we introduce Cultural Production as a complementary proxy for human development, particularly suited to long-term and cross-regional comparisons. Cultural production reflects the extent to which societies enable individuals to acquire knowledge, develop skills, and contribute to intellectual and artistic life-conditions closely tied to education, health, material security, and institutional support. We construct a global dataset tracking 122,634 distinct cultural producers (e.g., scientists, artists, writers) and apply ecological methods to estimate the number of unrecorded figures, correcting for differential survivorship bias. The resulting measure enables a broader and deeper reconstruction of human development across time and space. Our results challenge the prevailing view that meaningful development began only in modern Europe. We confirm that Western Europe experienced continuous gains from the 11th century onward, but we also uncover sustained growth in non-Western regions long before the 19th century. Japan shows multiple developmental phases, including a continuous rise after 1500 CE. In China, we trace human development back over 1,500 years, identifying major advances during the Han, Tang, and late imperial periods. In South and West Asia, we reveal marked progress under the Abbasid Caliphate and the Delhi Sultanate. Cultural Production also enables estimates of human development for Antiquity, showing developmental peaks in Classical Greece and Rome, though these were not sustained. Altogether, our findings suggest that all major regions, including non-European societies, transitioned from stagnation to sustained growth well before the Industrial Revolution-some as early as 1000 CE. These results suggest a more widespread and earlier pattern of human development across civilizations than previously recognized
Synthèse des connaissances sur les fourmis (Hymenoptera, Formicidae) du Parc national des Écrins (SE France)
No full textInternational audienceSynthesis of knowledge on the ants (Hymenoptera, Formicidae) of the Écrins national park (SE France). The synthesis of 1686 occurrence data of ants (family Formicidae, Hymenoptera) identified to the species level, distributed across the entire Écrins National Park (core zone and adhesion zone) revealed 83 species, i.e. more than one third of the myrmecofauna of metropolitan France. The species ac- cumulation curve shows, however, that the completeness of the inventory is moderate. Although the first data date back to 1984, more than 90% of the data have been obtained since 2018. To remedy to the knowledge deficit, the park adopted a strategy in 2018 which consisted in: first mobilizing park agents for opportunistic collections throughout the territory and an association of ant specialists for identification, and second occasionally involving ant specialists in field surveys. This sampling effort allowed exploring the distribution of diversity and species according to the type of environment and to elevation, and to reveal the presence of species that could represent an issue for the park. In particular, Formica paralugubris Seifert, 1996, a species of redwood ant endemic to the western Alps and the Jura, very little known in France, was detected in several sites. This species being difficult to distinguish from Formica lugubris Zetterstedt, 1838 – a very common boreomontane species – the identification was based on a double diagnosis: morphological and molecular. The inventory revealed other remarkable species such as Leptothorax gredleri Mayr, 1855, a species from central and northern Europe whose only known station in France is the one in the park, and Leptothorax pacis (Kutter, 1945), a very rare species occurring mainly in the Alps and the Pyrenees. A conservation value analysis relying on a method specific to the park revealed Formica paralugubris as a species with a particularly high conservation value within the territory of the park.La synthèse de 1686 données d’occurrence de fourmis (famille des Formicidae, Hymenoptera) identifiées à l’espèce réparties sur l’ensemble du parc national des Écrins (zone cœur et zone d’adhésion) a permis de recenser 83 espèces, soit plus du tiers de la myrmécofaune de France métropolitaine. La courbe d’accumulation des espèces montre cependant que la complétude de l’inventaire des espèces est modérée. Bien que les premières données datent de 1984, plus de 90 % des données ont été obtenues depuis 2018. Face au déficit de connaissance d’avant 2018, la stratégie du parc, qui s’est avérée efficace, a d’abord été de mobiliser les agents du parc pour des collectes opportunistes sur l’ensemble du territoire et une association spécialiste des fourmis pour l’identification, puis de faire intervenir ponctuellement des spécialistes sur le terrain. Cette pression d’échantillonnage a permis d’explorer la distribution de la diversité et des espèces en fonction du type de milieu et de l’altitude, et de révéler la présence d’espèces pouvant constituer un enjeu pour le parc. En particulier, Formica paralugubris Seifert, 1996, une espèce de fourmis rousse des bois endémique de l’ouest des Alpes et du Jura, très peu connue en France, a été détectée dans plusieurs stations. Cette espèce étant difficile à distinguer de Formica lugubris Zetterstedt, 1838, une espèce boréo-montagnarde très commune, l’identification a porté sur un double diagnostic, morphologique et moléculaire. L’inventaire a révélé d’autres espèces remarquables telles que Leptothorax gredleri Mayr, 1855, une espèce d’Europe centrale et du nord dont la seule station connue en France est celle du parc, et Leptothorax pacis (Kutter, 1945), une espèce très rare présente essentiellement dans les Alpes et les Pyrénées. L’évaluation de patrimonialité selon une méthode propre au parc n’a révélé qu’une seule espèce à considérer comme patrimoniale pour le parc : Formica paralugubris
The Political Economy of Mining Rent Sharing: Is Government Effectiveness Really Costly?
No full textInternational audienceThis paper builds on the work of a previous study to modelling the political economy factors that influence government take over the lifespan of mining projects. We extend the political economy model by incorporating the opportunity costs of preferences for side payments, thereby enhancing its predictive power to explain government take. Preferences for side payments are likely to exist only in contexts where government effectiveness is limited and corruption is rampant. Our empirical evidence using data on de jure government take in copper mining projects in Africa and Latin America confirms the theoretical predictions by the revisited political economy model. Specifically, we find that government effectiveness is a key driving factor with a two‐dimensional linkage. As government effectiveness improves, countries with high level of corruption experience lower government take, while those with high transparency and strong political regimes experience higher government take
Shaping research in marine functional connectivity for integrated and effective marine science and management
No full textInternational audienceEffective knowledge of ecological connectivity at sea and at the land-sea interface is key to supporting global policy goals to conserve and restore ocean biodiversity and function. However, a persistent lack of commonality in terminology and understanding around the concept of marine connectivity hampers its application in spatial planning and policy, and its integration across disciplines. Building on an extensive literature review, we clarify definitions and subcategories of connectivity, and propose a unified conceptual framework for Marine Functional Connectivity (MFC) research to support multidisciplinary marine science for improved management and policy. We identify key challenges and future directions for advancing this emerging field, bringing together most strands of marine science to understand changes in biodiversity and functional interdependencies between habitats and regions. Placing MFC research at the heart of marine environmental science promises to significantly improve predictions of environmental and socio-economic change and the sustainable use of ecosystems and resources at sea and at the land-sea interface
Molecular phylogeny of the Acer-feeding aphid subfamily Drepanosiphinae (Insecta: Hemiptera: Aphididae) and the evolution of its endosymbiotic consortia
No full textInternational audienceThe Drepanosiphinae is a Holarctic subfamily of Aphididae comprising six genera: Drepanaphis, Drepanosiphoniella, Drepanosiphum, Megalosiphonaphis, Shenahweum, and Yamatocallis, all of which exhibit strict host plant associations, primarily with Acer species. Despite long-standing taxonomic attention, evolutionary relationships within the group remain poorly resolved, and some important aspects of their biology, such as their patterns of association with symbionts, have been unexplored despite evidence that species in the subfamily might be involved in atypical nutritional symbioses. Here, we present a molecular phylogenetic reconstruction of this subfamily and investigate the evolution of its endosymbiotic consortia. Phylogenetic analyses were conducted using multiple DNA markers, employing both Bayesian inference (BI) and maximum likelihood (ML) approaches. Endosymbionts were characterized using high-throughput sequencing of a fragment of the bacterial 16S rRNA gene. The resulting phylogenies are largely congruent across markers and methods and consistently support the monophyly of Drepanosiphinae. Drepanaphis and Drepanosiphum form a well-supported clade as sister to Drepanosiphoniella, while Yamatocallis and Megalosiphonaphis form a distinct, more distantly related clade. Within Drepanaphis, species group according to host plant use rather than traditional morphological groupings, revealing three host-associated clades: rubrum, saccharum, and grandidentatum. Endosymbiont characterization revealed that, in addition to the obligate symbiont Buchnera aphidicola, most Drepanosiphinae species also host a Sodalis-like bacterium, consistent with previous genomic evidence for a dual nutritional symbiosis with this bacterium. However, Sodalis was absent in most Yamatocallis species, indicating a complex and potentially dynamic evolutionary history of symbiotic relationships within the subfamily. Patterns of association with Wolbachia, Rickettsia, Fukatsuia, Serratia and Arsenophonus suggest a limited role in nutrition. By integrating phylogenetic reconstruction with symbiont profiling, this study provides the most comprehensive evolutionary framework to date for Drepanosiphinae and reinforces the view that nutritional symbioses in aphids are evolutionarily dynamics
Energy flows reveal declining ecosystem functions by animals across Africa
No full textInternational audienceA key challenge for ecological science is to understand how biodiversity loss is changing ecosystem structure and function at scales that are relevant for policy1. Almost all biodiversity metrics are challenging to disaggregate into animal-mediated ecosystem functions such as pollination, seed and nutrient dispersal, and predation. Here we adopt an ecosystem energetics approach2 as a physically meaningful method of translating animal species composition into a suite of ecosystem functions. Drawing on new datasets that estimate biodiversity intactness and species population densities3,4,5, we quantify historical changes to energy flows through mammal- and bird-mediated ecosystem functions across sub-Saharan Africa. In total, trophic energy flows have decreased by more than one-third. The pattern of decreasing function varies by historical biome, driven by arboreal birds and primates in forests, terrestrial herbivores in grassy systems, and burrowing mammals in arid systems. Functions performed by megafauna in particular have collapsed outside protected areas. Compared with other biodiversity metrics, an energetics approach highlights the ecological importance of smaller animals and keystone species. The results can help practitioners conserve and restore functionally diverse, energetically intact ecosystems across land uses and biomes. By relating biodiversity intactness to energy and material flows, ecosystem energetics can also advance efforts to integrate animal-driven functions into biosphere and earth system models, helping us to understand possible regional or planetary boundaries6 for biodiversit
Diffusive gradient in thin film for ultra-trace methylmercury measurements in the coastal and open sea
No full textInternational audienceMonomethylmercury (MMHg) is a potent neurotoxin causing neurodevelopmental delays and cardiovascular and immunological issues. Human exposure primarily occurs through seafood consumption due to MMHg bioaccumulation and biomagnification from seawater into marine organisms. Determining MMHg in seawater at ultratrace concentrations poses logistical and analytical challenges. Diffusive Gradient in Thin-film (DGT) samplers represent a promising solution, which captures time-averaged concentrations by preconcentrating in situ MMHg over a defined exposure time. DGT manufactured with 3-mercaptopropyl-functionalized silica (3MFS) in agarose and polyacrylamide gels were tested and compared for the determination of MMHg present in open ocean and coastal waters. Different elution methods using acidic thiourea were tested to reach precise, accurate and quantitative elution of MMHg from the binding gel. We found that polyacrylamide-3MFS binding gels display a higher elution efficiency (94 ± 3 %), precision and better handling compared to agarose-3MFS gels (41 ± 6 %). A unique mooring line installed in the South Western Tropical Pacific Ocean, provided monthly DGT-MMHg concentrations over a year showing potential seasonal differences in MMHg concentrations ranging between 18 and 106 fM. DGT were also deployed in shallow Peruvian coastal waters, exhibiting higher MMHg concentrations (170 ± 97, n = 26) with typical benthopelagic gradients. DGT-MMHg concentrations were in good agreement with discrete water samples analyzed by reference methods using isotope dilution. DGTs offer complementary advantages over oceanographic cruises, notably in situ preconcentration, low blanks, minimal logistical requirements and cost-effectiveness. DGTs represent a valuable tool for studying the marine MMHg cycle for evaluating the implementation of the Minamata Convention
Chemical hydrogen storage materials – boranes and silanes catalytic solvolysis and dehydrogenation: a mechanistic and regeneration perspective
No full textInternational audienceHydrogen (H 2 ) has gained a lot of interest as an alternative energy vector, to reduce greenhouse gas emission issues caused by the fossil fuel industry. However, to make hydrogen a real energy carrier in a decarbonated economy, a secure and sustainable supply chain is needed. This approach requires notably safe storage and efficient strategies for recycling of raw materials. We discuss in this survey the state-of-the-art in the field of chemical hydrogen storage (CHS) materials, considering two possible vectors: ammonia borane and hydrosilanes. Regardless of the vector, to achieve real use, it is necessary to understand both the performance of the system and its life cycle, which relates to catalysts structure, and the activation of chemical bonds with efficient and complete catalytic cycles. We give herein an overview of hydrolysis and/or alcoholysis from metals, using coordination complexes, molecular supported catalysts or other materials, including nanocatalysts, with a focus on mechanistic information and understanding. Notably, the studies related to these two vectors can be considered somewhat complementary. Thus, the set of bibliographic report on ammonia borane is very documented in efficient catalytic systems, while its recycling remains at a very early stage. In comparison, hydrosilanes have been much less addressed specifically as a vector for hydrogen, while their reactivity at the molecular scale benefits from a relevant understanding from coordination chemistry studies. In addition, both hydrosilane polymerization and solvolysis reaction enables the release of H 2 , and produces by-products of which added value is already established. This opening the way to economical strategies where recycling can be optional. Nevertheless, the reversibility of hydrosilanes chemistry in H 2 uptake remains attractive and is another option to develop
High alpine preglacial caves modified by glacial processes and late condensationcorrosion in the Scerscen Valley (Valmalenco, Western Alps, Italy)
No full textInternational audienceThe Scerscen Valley (western Italian Alps) is home to caves at an altitude of around 2600 m, opening close to the Speleogenesis edge of a glacier. The aim of the research as part of a multi-disciplinary project was to reconstruct the evolution Alpine Cosmogenic GeomorphologyHydrogeologyglaciersburial dating of cosmonucleide some the of caves the related most burial recent to dating, the processes, geological recorded such and morphology paleoenvironmental as condensation-corrosion and micrometeorology, evolution and of sediment the carried area deposition. and out mineralogical to evaluate We the performed identifirole of cation by XRD, and hydrogeology using dye tracing and physical and chemical analyses. The cosmonucleide dating of quartz pebbles showed that the Veronica Cave is the oldest, with deposits dated at 1.3 ± 0.4 Ma, and possibly even older. It certainly formed at a much lower altitude (approx. 1300 m a.s.l. or lower) during the Alpine uplift. The Morgana and Marsooi caves, given the smaller volume of their phreatic conduits (1/3 of Veronica), are possibly more recent, formed during interglacials and evolved close to a glacial body. The caves initiated in dolomitic marble under the influence of sulfuric acid speleogenesis (SAS) due to pyrite oxidation. The conduits were then enlarged dramatically under phreatic conditions. The caves have evolved since their preglacial formation, with phases of filling by fluvio-glacial sediments and unclogging. Water tracing and physico-chemical analysis attest to a well-karstified aquifer, with rapid water circulation (>20 m/h) and low temperatures (~2 °C), draining towards the main spring, "La Prediletta", located at the foot of the dolomitic marbles. Microclimatic records (cave temperature and humidity) show seasonal cycles of condensation and evaporation, influenced by air exchanges with the outside atmosphere. These processes contributed to the formation of secondary minerals by evaporation (gypsum, hydromagnesite…) and, above all, to the significant enlargement of passages by the retreat of walls with characteristic morphologies (facets and grooved walls). The Scerscen caves bear witness to a long geological and climatic history, from their formation before the Mid-Pleistocene ice ages to their present-day evolution. They offer valuable insights into karst processes in the high mountains, and interactions between glaciers and aquifers