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Effective conservation requires maintenance of the processes underlying species divergence, as well as understanding species’ responses to episodic disturbances and long-term change. We explored genetic population structure at a previously unrecognized spatial scale in seabirds, focusing on fine-scale isolation between colonies, and identified two distinct genetic clusters of Barau’s Petrels ( Pterodroma baraui ) on Réunion Island (Indian Ocean) corresponding to the sampled breeding colonies separated by 5 km. This unexpected result was supported by long-term banding and was clearly linked to the species’ extreme philopatric tendencies, emphasizing the importance of philopatry as an intrinsic barrier to gene flow. This implies that loss of a single colony could result in the loss of genetic variation, impairing the species’ ability to adapt to threats in the long term. We anticipate that these findings will have a pivotal influence on seabird research and population management, focusing attention below the species level of taxonomic organization.

NASA’s Curiosity rover detected light-toned rocks along its traverse on Mars. Geochemical data suggest that the rocks represent a diversity of silica-rich magmatic rock types that may be analogous to Earth’s early continental crust. Understanding of the geologic evolution of Mars has been greatly improved by recent orbital 1 , 2 , 3 , in situ 4 , 5 and meteorite 6 , 7 , 8 data, but insights into the earliest period of Martian magmatism (4.1 to 3.7 billion years ago) remain scarce 9 . The landing site of NASA’s Curiosity rover, Gale crater, which formed 3.61 billion years ago 10 within older terrain 11 , provides a window into this earliest igneous history. Along its traverse, Curiosity has discovered light-toned rocks that contrast with basaltic samples found in younger regions 12 . Here we present geochemical data and images of 22 specimens analysed by Curiosity that demonstrate that these light-toned materials are feldspar-rich magmatic rocks. The rocks belong to two distinct geochemical types: alkaline compositions containing up to 67 wt% SiO 2 and 14 wt% total alkalis (Na 2 O + K 2 O) with fine-grained to porphyritic textures on the one hand, and coarser-grained textures consistent with quartz diorite and granodiorite on the other hand. Our analysis reveals unexpected magmatic diversity and the widespread presence of silica- and feldspar-rich materials in the vicinity of the landing site at Gale crater. Combined with the identification of feldspar-rich rocks elsewhere 9 , 13 , 14 and the low average density of the crust in the Martian southern hemisphere 15 , we conclude that silica-rich magmatic rocks may constitute a significant fraction of ancient Martian crust and may be analogous to the earliest continental crust on Earth.

The impacts of global climate change on marine ecosystems are of increasing concern. Because of their restricted distribution, endemic organisms are especially sensitive. In this context, we investigated the impact of climate change on the wintering habitats of Barau’s petrel Pterodroma baraui, an Endangered endemic species of Réunion Island (western Indian Ocean). Birds were tracked with Global Location Sensing loggers, over 3 different years. We built suitability models to determine the environmental drivers that influence habitat selection. These models were then used to predict changes in the location and size of the wintering habitats in 2100. After breeding, Barau’s petrels consistently migrate eastward to a large oceanic area in the central and eastern Indian Ocean (centred on the Ninety East Ridge). Three main factors best predicted the presence of wintering Barau’s petrels: surface wind speed, sea surface temperature and chlorophyll a concentration. Adult Barau’s petrels tended to select cool, oligotrophic areas with stronger than average winds. Based on these variables, we identified 3 distinct areas of high suitability. This suitable habitat is predicted to shift westward and southward in the future, as a consequence of global warming, and the surface of total suitable habitat for wintering Barau’s petrels may be reduced by an average of 11% by the year 2100. These predictions are discussed in terms of biological conservation and adaptation to climate change. Our study is among the first to demonstrate the utility of using current tracking data and habitat modelling to predict the long-term effects of climate change on marine birds.

The recent identification of large deposits of sulphates by remote sensing and in situ observations has been considered evidence of the past presence of liquid water on Mars. Here we report the unambiguous detection of diverse phyllosilicates, a family of aqueous alteration products, on the basis of observations by the OMEGA imaging spectrometer on board the Mars Express spacecraft. These minerals are mainly associated with Noachian outcrops, which is consistent with an early active hydrological system, sustaining the long-term contact of igneous minerals with liquid water. We infer that the two main families of hydrated alteration products detected—phyllosilicates and sulphates—result from different formation processes. These occurred during two distinct climatic episodes: an early Noachian Mars, resulting in the formation of hydrated silicates, followed by a more acidic environment, in which sulphates formed. Ebb and flow The OMEGA spectrometer, orbiting on board Mars Express, is scanning the martian surface for signs of specific minerals. It has now detected a family of clays known as phyllosilicates, produced when volcanic basalt encounters water for long periods. The minerals are found mainly in rocky outcrops deposited early in martian history. The presence of a second family of sulphates suggests that there was a later, sporadically wet period, characterized by more acidic conditions.

We studied the foraging ecology of a tropical seabird community in 2 islands of the Seychelles from 2005 to 2007. Chick dietary samples were used to compare feeding habits among species and assess inter-annual and seasonal variations in diet. Fish prey dominated the diet of the community (68 to 100% of prey consumed), although cephalopods were present in 61.3, 40.0, 27.1 and 32.9% of the food samples from white-tailed tropicbirds, sooty terns, brown noddies and wedge-tailed shearwaters, respectively. We found high diet overlap between species (Mullidae fish being the first prey consumed [30 to 90%] for all species except for the white-tailed tropicbird [<2%]) but some segregation in prey length. Other important prey were Exocoetidae, Carangidae, Scombridae and Clupeidae mainly for white-tailed tropicbirds, sooty terns and brown noddies, Hemiramphidae and Coryphaenidae for white-tailed tropicbirds, and Engraulidae and fish larvae for lesser noddies and Audubon’s shearwaters. Despite some inter-annual and seasonal variations in diet, these were not consistent within the community. Responses of the seabird community to an environmental perturbation that negatively affected chick growth and breeding success of lesser noddies emphasised the higher vulnerability of species with smaller foraging ranges and/or with lower ability to switch diet (lesser noddy, roseate tern) compared to less range-restricted and/or more opportunistic ones (white-tailed tropicbird, brown noddy, sooty tern, white tern). Although situated in a tropical region, the food availability in the Seychelles seems to be predictable at a large (annual) temporal scale, but highly unpredictable at a small (intra-seasonal or daily) temporal scale.

Global mineralogical mapping of Mars by the Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activité (OMEGA) instrument on the European Space Agency's Mars Express spacecraft provides new information on Mars' geological and climatic history. Phyllosilicates formed by aqueous alteration very early in the planet's history (the \"phyllocian\" era) are found in the oldest terrains; sulfates were formed in a second era (the \"theiikian\" era) in an acidic environment. Beginning about 3.5 billion years ago, the last era (the \"siderikian\") is dominated by the formation of anhydrous ferric oxides in a slow superficial weathering, without liquid water playing a major role across the planet.

ChemCam is a remote sensing instrument suite on board the “Curiosity” rover (NASA) that uses Laser-Induced Breakdown Spectroscopy (LIBS) to provide the elemental composition of soils and rocks at the surface of Mars from a distance of 1.3 to 7 m, and a telescopic imager to return high resolution context and micro-images at distances greater than 1.16 m. We describe five analytical capabilities: rock classification, quantitative composition, depth profiling, context imaging, and passive spectroscopy. They serve as a toolbox to address most of the science questions at Gale crater. ChemCam consists of a Mast-Unit (laser, telescope, camera, and electronics) and a Body-Unit (spectrometers, digital processing unit, and optical demultiplexer), which are connected by an optical fiber and an electrical interface. We then report on the development, integration, and testing of the Mast-Unit, and summarize some key characteristics of ChemCam. This confirmed that nominal or better than nominal performances were achieved for critical parameters, in particular power density (>1 GW/cm 2 ). The analysis spot diameter varies from 350 μm at 2 m to 550 μm at 7 m distance. For remote imaging, the camera field of view is 20 mrad for 1024×1024 pixels. Field tests demonstrated that the resolution (∼90 μrad) made it possible to identify laser shots on a wide variety of images. This is sufficient for visualizing laser shot pits and textures of rocks and soils. An auto-exposure capability optimizes the dynamical range of the images. Dedicated hardware and software focus the telescope, with precision that is appropriate for the LIBS and imaging depths-of-field. The light emitted by the plasma is collected and sent to the Body-Unit via a 6 m optical fiber. The companion to this paper (Wiens et al. this issue ) reports on the development of the Body-Unit, on the analysis of the emitted light, and on the good match between instrument performance and science specifications.

The current accelerated extinction tempo and the attendant decline in speciation rates are expected to segue into a mass-extinction event in the next few centuries. It cannot be stopped and will have profound implications for humans not yet born. What can be done? To begin, it is clear that the customary short-term conservation strategies with their scale mismatches fail to work in the long term, because they ignore the slow variables associated with deep time that ultimately drive the eco-evolutionary dynamics of ecosystems. Also, it is clear that large population ranges not only reduce extinction rates, but also enhance speciation rates. Hence, mitigation strategies for protecting as much evolutionary potential as possible during the forthcoming century and subsequent millennia (102-104 years) necessitate a focus on nonlinear, self-organizing, eco-evolutionary complexity that emerges from the slow processes embedded across expansive spatial and temporal scales. Management schemes for the effective protection of eco-evolutionary couplings include restoring apex predators, maintaining ecoevolutionary abundances of important species, linking bottom-up and top-down control of food webs, establishing and protecting corridors between ecosystems, strengthening the negative feedbacks that sustain eco-evolutionary interplay, and protecting and restoring biodiversity and biodisparity. Moreover, given that the vast majority of ecosystems worldwide are human dominated, it is imperative that the geographical range of diverse biota be expanded into these anthropogenic habitats, a sharing of living space promoted by reconciliation ecology. To illustrate the theoretical efficacy of the above, we briefly apply

Excessive weight gain after initiation of antiretroviral therapy (ART) has become a recognized concern among people living with HIV. Individual weight trajectories remain highly heterogeneous and challenging to predict using conventional methods. We leveraged the French Dat’AIDS national cohort to assess whether machine learning (ML) could enhance the prediction of individual body weight at 6, 12, and 24 months after ART initiation. Using 112 baseline variables encompassing demographic, clinical, laboratory, and treatment-related data, we trained XGBoost models and evaluated performance using root mean square error (RMSE), R², and mean prediction error. A simple benchmark model based on baseline weight was used for comparison. Among 24,014 eligible ART-naïve adults, the ML models achieved RMSEs of approximately 4.6 kg, 5.3 kg, and 6.4 kg at 6, 12, and 24 months respectively, with declining predictive power over time. Baseline weight (Weight_M0) consistently emerged as the strongest predictor, while other factors contributed minimally. Although ML marginally outperformed the benchmark (Weight_M0), accuracy remained insufficient for clinical decision-making. Sensitivity analyses excluding individuals with implausibly large monthly weight changes modestly improved RMSE (3.9–6.0 kg), underscoring the impact of data quality. Our results demonstrate that, despite large sample size and rich clinical variables, ML lacks the precision necessary for individual weight forecasting in this context. These findings highlight the limitations of applying artificial intelligence to heterogeneous real-world cohorts and underscore the need to incorporate behavioral and lifestyle factors to improve predictive modeling.

Slope movements of material in lunar craters are investigated based on remote spectral studies carried out on board the Clementine spacecraft, and data obtained during the large-scale survey on board the LRO (Lunar Reconnaissance Orbit) spacecraft. The morphological analysis of crater forms based on large-scale images and spectral and spectropolarized assessments of the exposition age (or maturity) of the slope material has led to the conclusion that the formation process of observed outcrops probably is a modern feature. The lower age limit of these structures is estimated at 40–80 years. Thus, slope movements of surface materials can continue at the present time, regardless of the age of the crater studied. Slope movements of crushed granular material lead to fresh outcrops of subsurface layers of marine or continental landscapes and, therefore, extend our capabilities to research the deep material of the Moon. To analyze this phenomenon, craters of 16 and 30 km have been selected. The length of fresh outcrops, while depending strongly on the dimensions of the craters, can be up to several kilometers. In connection with this, the prospect appears of remote analysis of rocks that came to the surface from depths of at least several hundred meters. In this case, there are openings for the contact analysis of subsurface material without the use of labor-intensive operations associated with the delivery of equipment for deep drilling to the lunar surface.