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Guillaume Deschasse,1,2 Elodie Drumez,2,3 Fabien Visade,2,4 Anne Charpentier,5 Céline Delecluse,4 Gilles Loggia,6,7 Pascale Lescure,7 Jadwiga Attier-Żmudka,8,9 Jennifer Bloch,5 Cédric Gaxatte,5 Frédéric Bloch,1 François Puisieux,5 Jean-Baptiste Beuscart2,5 1Department of Geriatrics, CHU Amiens-Picardie, Amiens, France; 2ULR 2694 - METRICS: Évaluation des technologies de santé et des pratiques médicales, University Lille, CHU Lille, Lille, France; 3Department of Biostatistics, CHU Lille, Lille, France; 4Geriatrics Department, Lille Catholic Hospitals, Lille, France; 5Department of Geriatrics, CHU Lille, Lille, France; 6COMETE, INSERM, Normandie Univ, UNICAEN, Caen, France; 7Department of Geriatrics, Normandie Univ, UNICAEN, CHU de Caen Normandie, Caen, France; 8Geriatric Department, General Hospital of Saint-Quentin, Saint-Quentin, France; 9CHIMERE EA 7516 Team Research, Jules Verne University, Amiens, FranceCorrespondence: Guillaume Deschasse, Department of Geriatrics, CHU Amiens-Picardie, Amiens, France, Tel +33-322-088-000, Fax + 33-322-455-748, Email deschasse.guillaume@chu-amiens.frBackground: Acute geriatric units (AGUs) require efficient discharge planning tools. Risk factors for discharge from an AGU to post-acute care (PAC) have not previously been investigated in detail.Methods: The objective is to identify risk factors for PAC transfer. The DAMAGE (prospective multicenter cohort) consecutively included more than 3500 subjects aged 75 or older and admitted to an AGU. The patients underwent a comprehensive geriatric assessment (CGA) during their stay in the AGU. Only community-dwelling patients admitted to the AGU from the emergency department were included in the analysis. We recorded the characteristics of the care pathway and identified risk factors for discharge to home or to a PAC facility.Results: 1928 patients were included. Loss of functional independence (a decrease in the Katz activities of daily living (ADL) score between 1 month prior to admission and AGU admission), living alone, social isolation, a high Katz ADL score at home, a low Katz ADL on admission, and delirium on admission were risk factors for transfer to PAC. Obesity, an elevated serum albumin level, and community-acquired infection were associated with discharge to home. Neither sex nor age was a risk factor for home discharge or transfer to PAC.Conclusion: The present results might help clinicians and discharge planning teams to identify patients at risk of transfer to PAC more reliably and promptly in AGUs.Keywords: care transitions, health services, rehabilitation, risk factors, acute geriatric unit

International audience; OBJECTIVES: Comfort care for a dying patient increases the quality of the end of life. End-of-life situations are frequently managed in acute geriatric units (AGUs), and transition to comfort care only is often necessary. However, the frequency of transition to comfort care and the latter's putative link with the end-of-life trajectory (sudden death, cancer, organ failure, and frailty with or without dementia) have not previously been studied in acute geriatric units. We sought to (1) describe end-of-life trajectories and the transition to comfort care only, and (2) analyse the relationship between the two, prior to death in an AGU. DESIGN: A secondary analysis of a subgroup of the DAMAGE cohort (a prospective multicentre cohort of 3509 patients aged 75~years and over and admitted consecutively to an AGU). SETTING/PARTICIPANTS: DAMAGE patients who died in an AGU after a stay of at least 48~hours. METHODS: Data on the end-of-life trajectory and the transition to comfort care only were extracted from medical records. RESULTS: Of the 177 included patients, 123 (69.5%) transitioned to comfort care only in the AGU. A frailty trajectory (in patients living with dementia or not) accounted for nearly 70% of deaths. Paradoxically, only frailty among people living without dementia was not significantly associated with a more frequent transition to comfort care [odds ratio (95% confidence interval): 1.44 (0.44-4.76), relative to a patient dying suddenly]. CONCLUSIONS AND IMPLICATIONS: Transition to comfort care only is frequent in AGUs and is linked to the end-of-life trajectory (except for frail patients living without dementia). The frailty trajectory is one of the most frequent, and, therefore, physicians must be aware of the need to improve practice in this context.

The estimation of population size and its variation across space and time largely relies on counts of individuals, generally carried out within spatial units such as quadrats or sites. Missing individuals during counting (i.e. imperfect detection) results in biased estimates of population size and trends. Imperfect detection has been shown to be the rule in animal studies, and most studies now correct for this bias by estimating detection probability. Yet this correction remains exceptional in plant studies, suggesting that most plant ecologists implicitly assume that all individuals are always detected.To assess if this assumption is valid, we conducted a field experiment to estimate individual detection probability in plant counts conducted in 1×1 m quadrats. We selected 30 herbaceous plant species along a gradient of conspicuousness at 24 sites along a gradient of habitat closure, and asked groups of observers to count individuals in 10 quadrats using three counting methods requiring progressively increasing times to complete (quick count, unlimited count and cell count). In total, 158 participants took part in the experiment, allowing an analysis of the results of 5,024 counts.Over all field sessions, no observer succeeded in detecting all the individuals in the 10 quadrats. The mean detection rate was 0.44 (ranging from 0.11 to 0.82) for the quick count, 0.59 for the unlimited count (range 0.18–0.87) and 0.74 for the cell count (range 0.46-0.94).Detection probability increased with the conspicuousness of the target species and decreased with the density of individuals and habitat closure. The observer’s experience in botany had little effect on detection probability, whereas detection was strongly affected by the time observers spent counting. Yet although the more time-consuming methods increased detection probability, none achieved perfect detection, nor did they reduce the effect on detection probability of the variables we measured.Synthesis. Our results show that detection is imperfect and highly heterogeneous when counting plants. To avoid biased estimates when assessing the size, temporal or spatial trends of plant populations, plant ecologists should use methods that estimate the detection probability of individuals rather than relying on raw counts.

International audience; Population size is a crucial parameter for both ecological research and conservation planning. When individuals are aggregated, estimating the size of a population through sampling raises methodological challenges, as the high variance between sampling units leads to imprecise estimates. Choosing the right sample design depending on the population aggregation level could improve the precision of estimates; however, this is difficult because studies comparing sample designs for aggregated populations have been limited to a few populations and sampling designs, so their results cannot be generalised. To address this gap, we combined simulations of spatial point populations and field counts of three plant species to compare the relative precision of estimates between three sampling methods: simple random sampling (SRS), systematic sampling (SYS) and spatially balanced sampling (SBS). Comparisons were performed on density and aggregation gradients for a range of sample sizes. Our simulations showed that SYS and SBS were always more precise than SRS when individuals were aggregated, reducing sampling variance up to 80% and 60%. The highest precision for estimating population size was always obtained when the average distance between sampling units equalled the diameter of the clusters (i.e. the groups of individuals). The difference in precision was similar for the natural populations, with sampling variance lowered by up to 75% (SYS) and 60% (SBS) compared to SRS. These findings lead us to recommend using SYS or SBS rather than SRS to estimate population size when individuals are spatially aggregated, as these consistently provide more precise estimates. Assessing cluster diameters in the field enables a quick assessment of the potential gain in precision to expect, and thus the best choice of sampling method depending on the trade-off between precision and field constraints.

Background There is a need for a mortality score that can be used to trigger advanced care planning among older patients discharged from acute geriatric units (AGUs). Objective We developed a prognostic score for 3- and 12-month mortality after discharge from an AGU, based on a comprehensive geriatric assessment, in-hospital events, and the exclusion of patients already receiving palliative care. Methods Devenir Après la Médecine Aigue Gériatrique (DAMAGE) is a French multicenter, prospective, cohort study. The broad inclusion criteria ensured that the cohort is representative of patients treated in an AGU. The DAMAGE participants underwent a comprehensive geriatric assessment, a daily clinical checkup, and follow-up visits 3 and 12 months after discharge. Multivariable logistic regression models were used to develop a prognostic score for the derivation and validation subsets. Results A total of 3 509 patients were assessed and 3 112 were included. The patient population was very old and frail or dependant, with a high proportion of deaths at 3 months (n = 455, 14.8%) and at 12 months (n = 1 014, 33%). The score predicted an individual risk of mortality ranging from 1% to 80% at 3 months and between 5% and 93% at 12 months, with an area under the receiving operator characteristic curve in the validation cohort of 0.728 at 3 months and 0.733 at 12 months. Conclusions Our score predicted a broad range of risks of death after discharge from the AGU. Having this information at the time of hospital discharge might trigger a discussion on advanced care planning and end-of-life care with very old, frail patients. Clinical Trials Registration Number: NCT02949635

Objectives Chest CT has been widely used to screen and to evaluate the severity of COVID-19 disease in the early stages of infection without severe acute respiratory syndrome, but no prospective data are available to study the relationship between extent of lung damage and short-term mortality. The objective was to evaluate association between standardized simple visual lung damage CT score (vldCTs) at admission, which does not require any software, and 30-day mortality. Methods In a single-center prospective cohort of COVID-19 patients included during 4 weeks, the presence and extent of ground glass opacities(GGO), consolidation opacities, or both of them were visually assessed in each of the 5 lung lobes (score from 0 to 4 per lobe depending on the percentage and out of 20 per patient = vldCTs) after the first chest CT performed to detect COVID-19 pneumonia. Results Among 210 confirmed COVID-19 patients, the number of survivors and non-survivors was 162 (77%) and 48 (23%), respectively at 30 days. vldCTs was significantly higher in non-survivors, and the AUC of vldCTs to distinguish survivors and non-survivors was 0.72 (95%CI 0.628–0.807, p < 0.001); the best cut-off vldCTs value was 7. During follow-up, significant differences in discharges and 30-day mortality were observed between patients with vldCTs ≥ 7 versus vldCTs < 7: (98 [85.2%] vs 49 [51.6%]; p < 0.001 and 36 [37.9%] vs 12 [12.4%]; p < 0.001, respectively. The 30-day mortality increased if vldCTs ≥ 7 (HR, 3.16 (1.50–6.43); p = 0.001), independent of age, respiratory rate and oxygen saturation levels, and comorbidities at admission. Conclusions By using chest CT in COVID-19 patients, extensive lung damage can be visually assessed with a score related to 30-day mortality independent of conventional risk factors of the disease. Key Points • In non-selected COVID-19 patients included prospectively during 4 weeks, the extent of ground glass opacities(GGO) and consolidation opacities evaluated by a simple visual score was related to 30-day mortality independent of age, respiratory rate, oxygen saturation levels, comorbidities, and hs-troponin I level at admission. • This severity score should be incorporated into risk stratification algorithms and in structured chest CT reports requiring a standardized reading by radiologists in case of COVID-19. Supplementary Information The online version contains supplementary material available at 10.1007/s00330-021-07938-2.

The role of urban areas in the introduction of alien plant species, and their subsequent spread in the countryside, has long been identified. However, it was mainly considered indirectly due to the lack of data on the frequency of planting of alien species and their early stages of colonization. In this study, we took advantage of the spectacular flowering of the pampa grass (Cortaderia selloana), a tall ornamental plant, visible from afar, to study the spatial dynamics of planted and naturalized stands (i.e. those resulting from seed dispersal) over 600 km2 and over an 11-year period. Using distance sampling methods, we detected 216 and 241 planted stands in 2002 and 2013, respectively. In 2002, we also detected 853 naturalized stands, closely associated with anthropogenic habitats around urban areas. Such spatial association could have represented the initial stages of a spread from urban areas to natural habitats. However, 11 years later, this very close association between naturalized stands and urban areas has not weakened, suggesting a persistent pattern. In both 2002 and 2013, less than 15% of naturalized individuals grew up in natural habitats, almost all limited to the edges of reed beds where they did not threaten local biodiversity. Our study shows that the massive introduction of an alien plant into urban areas, and its subsequent massive naturalization, does not necessarily means its spread to natural habitats. On the contrary, it can remain closely associated with anthropogenic habitats.

Background Surgical lung biopsy is essential in the diagnostic algorithm of interstitial lung disease (ILD) of unknown cause. Safety concerns have been recently reiterated. The aim of this study was to prospectively assess the yield of diagnosis and safety of video-assisted thoracoscopic surgical lung biopsy (VATS-LB) for ILD diagnosis. Methods This prospective study, conducted in 6 ILD-referral Paris hospitals, included 103 patients with ILD. After initial multidisciplinary discussion, VATS-LB was proposed. A final diagnosis was made after the procedure, during a second multidisciplinary discussion. The main outcome was to determine the final diagnoses and their proportion after VATS-LB. Other outcomes were the percentage of change in diagnosis and treatment propositions after VATS-LB and adverse events during 3 months after surgery, postoperative pulmonary function, quality of life and pain. Results A definite diagnosis was reached in 87 cases (84.4%), while 16 remained unclassifiable (15.6%). Hypothesized diagnosis and treatment changed after VATS-LB in 65 (63.1%) and in 41 patients (39.8%), respectively. There was one death due to acute exacerbation. In-hospital complications were predicted by a lower preoperative distance at 6-minute walking test and by forced vital capacity lower than 77%. Postoperative quality of life was not modified at 3 months while forced vital capacity decreased slightly. Postoperative neuropathic pain was revealed in 5% and 2% patients at 1 and 3 months, respectively. Conclusions VATS-LB dramatically changed preoperative hypothetical diagnoses and treatment in ILD of unknown cause with good patient survival in ILD-referral centers.

Protected areas (PAs) are a key element of global conservation strategies aiming to protect habitats and species from various threats such as non-natives species (NNS) with negative ecological impacts. Yet little is known about the mechanisms by which PAs are colonized by NNS, and more specifically the role of colonizing events from surrounding areas. Here, we compared terrestrial and freshwater non-native plants and animals recorded in Norwegian PAs and in 5-km belts around them, using the database of the Norwegian Biodiversity Information Centre Species Map Service. Our analysis included 1,602 NNS and 671 PAs. We found that NNS were recorded in only 23% of the PAs, despite the fact that 90% of the 5-km belts were colonized by at least one NNS. A Zero-inflated negative binomial regression model showed that the number of NNS in the 5-km belts was a strong explanatory variable of the NNS richness inside PAs. Other significant variables included the surface area of the PA, mean human population density in the PA, main type of habitat and accessibility of PAs. We also observed similarity in the species in and around the PAs, with, on average, two thirds of the NNS present in a specific PA also present in its 5-km belt. Furthermore, NNS were recorded in PAs on average 4.5 years after being recorded in the 0–5 km belts, suggesting a dynamic of rapid colonization from the belts to the PAs. Invasive NNS represented 12% of NNS in the belts but 40% in the PAs. This difference was related to the higher abundance of invasive NNS in the belts. Our results highlight the necessity of expanding the focus of NNS management in PAs beyond their boundaries, in particular to prevent incursions of NNS with high negative ecological impact.

International audience; Ancient human-whale relationships are difficult to study because, counterintuitively, whales have been virtually invisible in the archaeological record despite the immense quantities of valuable products they provide. In this review, we explain the reasons for this invisibility, and we also show how an interdisciplinary approach combining archaeological and ethnographic studies with new biomolecular and isotopic techniques is yielding new insights, allowing a broader perspective on what whale bones found in archaeological sites or collections can tell us. Until recently, the rare whale bones found in archaeological sites were often overlooked or misidentified. The recent development of biomolecular methods, including ancient DNA analyses and collagen peptide mass fingerprinting (ZooMS), has enabled reliable identification of whale species from even small bone fragments. In addition, stable isotope analyses can provide information about ancient whale diets, feeding habits, migrations, or even environmental changes. Combined with radiocarbon dating, these approaches provide valuable ecological and historical context for whale conservation.

Ecological baselines—reference states of species' distributions and abundances—are key to the scientific arguments underpinning many conservation and management interventions, as well as to the public support to such interventions. Yet societal as well as scientific perceptions of these baselines are often based on ecosystems that have been deeply transformed by human actions. Despite increased awareness about the pervasiveness and implications of this shifting baseline syndrome, ongoing global assessments of the state of biodiversity do not take into account the long-term, cumulative, anthropogenic impacts on biodiversity. Here, we propose a new framework for documenting such impacts, by classifying populations according to the extent to which they deviate from a baseline in the absence of human actions. We apply this framework to the bowhead whale ( Balaena mysticetus ) to illustrate how it can be used to assess populations with different geographies and timelines of known or suspected impacts. Through other examples, we discuss how the framework can be applied to populations for which there is a wide diversity of existing knowledge, by making the best use of the available ecological, historical and archaeological data. Combined across multiple populations, this framework provides a standard for assessing cumulative anthropogenic impacts on biodiversity. This article is part of a discussion meeting issue ‘The past is a foreign country: how much can the fossil record actually inform conservation?’

How did ancient communities around the Mediterranean exploit the presence of whales in their seas? Given that the whales currently present in the region are seldom found near the coast, it seems probable that ancient whale exploitation would have been restricted to stranded animals. The authors explore, however, the possibility that additional species migrated seasonally through the Strait of Gibraltar to visit coastal calving grounds, which could have supported an organised whaling industry. Classical literature provides a number of descriptions suggestive of coastal encounters with whales. New methods of whale bone identification will shed light on which species were previously present in the Mediterranean and thus on the probability of ancient whaling. This article is one of two on ancient whaling in the current issue, and should be read in conjunction with that by Dario Bernal-Casasola and colleagues.

This account presents information on all aspects of the biology and ecology of Baccharis halimifolia L. that are relevant to understanding its invasive behaviour. The main topics are presented within the framework of the new series of Botany Letters on Monographs on invasive plants in Europe: taxonomy, distribution, history of introduction and spread, ecology (including preferred climate and habitats, responses to abiotic and biotic factors, ecological interactions), biology (including physiology, phenology and reproductive biology), impacts and management. Baccharis halimifolia L. (Asteraceae), groundsel bush, is a broad-leaved shrub native to the coastal area of southeastern North America. Introduced for ornamental and amenity purposes during the nineteenth century, it has become naturalized in several coastal habitats, as well as in disturbed areas of western Europe. The shrub is now common on the Atlantic coast of Europe from northern Spain to Belgium and it is an emerging problem on the Medit...

Right whales ( Eubalaena glacialis ) were extirpated from the eastern North Atlantic by commercial whaling. Grey whales ( Eschrichtius robustus ) disappeared from the entire North Atlantic in still-mysterious circumstances. Here, we test the hypotheses that both species previously occurred in the Mediterranean Sea, an area not currently considered part of their historical range. We used ancient DNA barcoding and collagen fingerprinting methods to taxonomically identify a rare set of 10 presumed whale bones from Roman and pre-Roman archaeological sites in the Strait of Gibraltar region, plus an additional bone from the Asturian coast. We identified three right whales, and three grey whales, demonstrating that the ranges of both of these species historically encompassed the Gibraltar region, probably including the Mediterranean Sea as calving grounds. Our results significantly extend the known range of the Atlantic grey whale, and suggest that 2000 years ago, right and grey whales were common when compared with other whale species. The disappearance of right and grey whales from the Mediterranean region is likely to have been accompanied by broader ecosystem impacts, including the disappearance of their predators (killer whales) and a reduction in marine primary productivity. The evidence that these two coastal and highly accessible species were present along the shores of the Roman Empire raises the hypothesis that they may have formed the basis of a forgotten whaling industry.

As economic and social contexts become more embedded within biodiversity conservation, it becomes obvious that resources are a limiting factor in conservation. This recognition is leading conservation scientists and practitioners to increasingly frame conservation decisions as trade-offs between conflicting societal objectives. However, this framing is all too often done in an intuitive way, rather than by addressing trade-offs explicitly. In contrast, the concept of trade-off is a keystone in evolutionary biology, where it has been investigated extensively. I argue that insights from evolutionary theory can provide methodological and theoretical support to evaluating and quantifying trade-offs in biodiversity conservation. I reviewed the diverse ways in which trade-offs have emerged within the context of conservation and how advances from evolutionary theory can help avoid the main pitfalls of an implicit approach. When studying both evolutionary trade-offs (e.g., reproduction vs. survival) and conservation trade-offs (e.g., biodiversity conservation vs. agriculture), it is crucial to correctly identify the limiting resource, hold constant the amount of this resource when comparing different scenarios, and choose appropriate metrics to quantify the extent to which the objectives have been achieved. Insights from studies in evolutionary theory also reveal how an inadequate selection of conservation solutions may result from considering suboptimal rather than optional solutions when examining whether a trade-off exits between 2 objectives. Furthermore, the shape of a trade-off curve (i.e., whether the relationship between 2 objectives follows a concave, convex, or linear form) is known to affect crucially the definition of optimal solutions in evolutionary biology and very likely affects decisions in biodiversity conservation planning too. This interface between evolutionary biology and biodiversity conservation can therefore provide methodological guidance to support decision makers in the difficult task of choosing among conservation solutions. Percepciones de la Teoria de Historia de Vida para una Tratamiento Explicito de las Compensaciones en la Biologia de la Conservacion Resumen A la vez que los contextos economicos y sociales se involucran mas en la conservacion de la biodiversidad, se vuelve obvio que los recursos son un factor limitante en la conservacion. Este reconocimiento esta llevando a los cientificos de la conservacion y a quienes la practican a enmarcar frecuentemente a las decisiones de conservacion como compensaciones entre objetivos sociales en conflicto. Sin embargo, esto suele hacerse de manera intuitiva, en lugar de dirigirse explicitamente a las compensaciones. En contraste, el concepto de compensacion es una piedra angular en la biologia evolutiva, en donde se ha investigado extensivamente. En este articulo discuto que las percepciones de la teoria evolutiva pueden proporcionar apoyo teoretico y metodologico a la evaluacion y cuantificacion de las compensaciones en la conservacion de la biodiversidad. Revise las diversas formas en las que las compensaciones han emergido dentro del contexto de la conservacion y como los avances de la teoria evolutiva pueden ayudar a evitar las principales dificultades de un enfoque implicito. Al estudiar las compensaciones evolutivas (p. ej.: reproduccion vs. supervivencia) y las compensaciones de conservacion (p. ej.: conservacion de la biodiversidad vs. agricultura), es importante identificar correctamente al recurso limitante, mantener como constante el aumento de este recurso al compararlo con escenarios diferentes y elegir las medidas apropiadas para cuantificar el alcance al que se han logrado los objetivos. Las percepciones de estudios de la teoria evolutiva tambien revelan como una seleccion no adecuada de soluciones de conservacion puede resultar de considerar soluciones sub-optimas en lugar de soluciones opcionales al examinar si las compensaciones salen de entre dos objetivos. Ademas, se sabe que la forma de la curva de compensacion (es decir, si la relacion entre dos objetivos sigue una forma concava, convexa o lineal) afecta crucialmente la definicion de las soluciones optimas en la biologia evolutiva y muy probablemente tambien afecte a las decisiones en la planeacion de la biologia de la conservacion. Esta interconexion entre la biologia evolutiva y la conservacion de la biodiversidad puede proporcionarnos asi una guia metodologica que apoye a quienes toman las decisiones en la dificil labor de elegir entre las soluciones de conservacion.

International audience; One contribution of 16 to a theme issue 'From DNA barcodes to biomes'. Over the last few centuries, many cetacean species have witnessed dramatic global declines due to industrial overharvesting and other anthropogenic influences, and thus are key targets for conservation. Whale bones recovered from archaeological and palaeontological contexts can provide essential baseline information on the past geographical distribution and abundance of species required for developing informed conservation policies. Here we review the challenges with identifying whale bones through traditional anatomical methods, as well as the opportunities provided by new molecular analyses. Through a case study focused on the North Sea, we demonstrate how the utility of this (pre)historic data is currently limited by a lack of accurate taxonomic information for the majority of ancient cetacean remains. We then discuss current opportunities presented by molecular identification methods such as DNA barcoding and collagen peptide mass fingerprinting (zooarchaeology by mass spectrometry), and highlight the importance of molecular identifications in assessing ancient species' distributions through a case study focused on the Mediterranean. We conclude by considering high-throughput molecular approaches such as hybridization capture followed by next-generation sequencing as cost-effective approaches for enhancing the ecological informativeness of these ancient sample sets. This article is part of the themed issue 'From DNA barcodes to biomes'.

Summary 1. The production of variably sized offspring has been hypothesized to be adaptive to temporal variability in environmental conditions. 2. This is difficult to verify empirically, and theoretical models are typically generic and not parameterized with data from real populations; studies integrating theoretical and empirical approaches to this problem are rare. 3. Here, we present experimental data on the growth of Scirpus maritimus, a clonal aquatic macrophyte that grows through vegetative extensions involving tubers. 4. The experiments show that offspring fitness (biomass productivity) is dependent on environmental conditions (water depth). 5. Experimental data indicate that variation in offspring (tuber) sizes can be approximated by a lognormal distribution. 6. We use these data to develop a different equation model of S. maritimus growth to test whether producing variably sized offspring is adaptive. The model compares fitness under the lognormal strategy to several hypothetical strategies with qualitatively different variance in offspring size. 7. The model results suggest that lognormal variation in S. maritimus tuber size may be adaptive to the temporal variation in water levels that characterize its natural Mediterranean environment. 8. We illustrate how the underlying principles that lend adaptive value to offspring size variation may apply to other species experiencing similar environmental conditions. 9. Synthesis. Close integration of data and theoretical models creates a unique tool for investigating the adaptive value of life-history traits in clonal aquatic plants.

Bolboschoenus maritimus, a clonal species, is locally invasive in Mediterranean temporary pools where it threatens endangered rare plant species such as Isoetes setacea. The combination of management modifications (grazing) and of the progressive accumulation of fine sediments in the pools contributed to the establishment of competitive perennial plants such as B. maritimus. The competitive advantage of B. maritimus on I. setacea has been studied in controlled conditions. The goal of this experiment was to assess the role of environmental conditions in the output of the competition between Bolboschoenus and Isoetes, notably hydrology and soil richness. For this purpose, Isoetes was cultivated alone (three individuals/pot) and with Bolboschoenus (three individuals of both species). The experiment was run with five replicates on six types of sediment (gradient of richness in sand/silt/clay) combined with three hydrological treatments (flooded, wet. and dry). The competitive advantage of Bolboschoenus was measured as the ratio of the production of Isoetes in mixture versus monoculture. The results showed that Isoetes was always outcompeted by Bolboschoenus. However, the competitive advantage of Bolboschoenus on Isoetes, was more related to hydrology than to soil richness. The competitive advantage of Bolboschoenus was very high in wet and flooded conditions and very low in dry conditions. This situation may lead to the extinction, medium-term, of the populations of I. setacea. The introduction of ovine grazing or of cut back practices in temporary pools could reduce the B. maritimus biomass and help toward the conservation of I. setacea populations.

Mediterranean temporary pools represent unique species-rich habitats with many rare and endangered species. The Roque-Haute Natural Reserve is one of the few sites in France with Isoetes setacea Lam., a very rare Mediterranean quillwort, considered as a keystone species determining a priority habitat for the European Union. Land uses changes have favoured the invasion of the pools by several shrub and tree species (e.g., Ulmus minor, Fraxinus angustifolia subsp. oxycarpa). Clearing shrubs in an experimental area of one pool resulted in the increase of I. setacea as compared to control, combining a higher cover in previously occupied quadrats and more quadrats occupied. Litter accumulation had a negative effect on the population of Isoetes but this effect was detectable only in the cleared area. Light attenuation was shown experimentally to be detrimental to the vegetative and regenerative production of I. setacea. Clearing of the shrubs and removal of the litter led to an increase in the I. setacea populations and therefore appears to be an effective technique for restoring these plant communities invaded by shrubs. Long-term shrub control should be ensured by reintroducing sheep grazing in order to enhance the sustainable conservation of this oligotrophic habitat.

As economic and social contexts become more embedded within biodiversity conservation, it becomes obvious that resources are a limiting factor in conservation. This recognition is leading conservation scientists and practitioners to increasingly frame conservation decisions as trade-offs between conflicting societal objectives. However, this framing is all too often done in an intuitive way, rather than by addressing trade-offs explicitly. In contrast, the concept of trade-off is a keystone in evolutionary biology, where it has been investigated extensively. I argue that insights from evolutionary theory can provide methodological and theoretical support to evaluating and quantifying trade-offs in biodiversity conservation. I reviewed the diverse ways in which trade-offs have emerged within the context of conservation and how advances from evolutionary theory can help avoid the main pitfalls of an implicit approach. When studying both evolutionary trade-offs (e.g., reproduction vs. survival) and conservation trade-offs (e.g., biodiversity conservation vs. agriculture), it is crucial to correctly identify the limiting resource, hold constant the amount of this resource when comparing different scenarios, and choose appropriate metrics to quantify the extent to which the objectives have been achieved. Insights from studies in evolutionary theory also reveal how an inadequate selection of conservation solutions may result from considering suboptimal rather than optional solutions when examining whether a trade-off exits between 2 objectives. Furthermore, the shape of a trade-off curve (i.e., whether the relationship between 2 objectives follows a concave, convex, or linear form) is known to affect crucially the definition of optimal solutions in evolutionary biology and very likely affects decisions in biodiversity conservation planning too. This interface between evolutionary biology and biodiversity conservation can therefore provide methodological guidance to support decision makers in the difficult task of choosing among conservation solutions.

Positive plant-plant interactions are known to increase species richness in stressful and poor habitats that are often species poor, but the role of facilitative interactions in species-rich communities is less well understood. It has been proposed that allelopathic plants may create non-transitive species interactions, which increase species coexistence, and that such indirect facilitation may be important in species-rich communities. We examined species richness in 12 different plant communities all dominated by the aromatic Thymus vulgaris that produces monoterpenes known to inhibit germination and growth of other plants. We found consistently, and across communities, higher species richness in microsites with thyme than without. Species richness in microsites with, respectively without, two other perennial plants did not differ, suggesting that increased species richness in thyme microsites is due to the presence of thyme. We found a more similar species composition among thyme microsites and positive estimates of thyme on landscape richness enhancement, indicating that thyme also affect richness at the community level. However, across communities, we did not find species consistently confined to thyme microsites, albeit within communities some plants were exclusive to thyme. Abundance of a dominant grass was reduced in microsites where thyme produces the monoterpene carvacrol, suggesting that one mechanism by which thyme facilitates species richness was by the repression of a superior competitor that could allow other species to persist. However, this does not explain higher species richness in microsites of thyme producing other monoterpenes. We discuss how chemical variation in thyme and adaptation of associated species to local monoterpenes may affect richness and community diversity. Synthesis. Allelopathic plants are generally believed to negatively impact upon the performance of associated species. However, allelopathic plants may be important determinants of species richness at the community level by creating microenvironments where species-specific interactions differ. Our finding shows that thyme increases species richness both locally and at the community level by creating a mosaic of thyme-modified and unmodified microsites differing in richness and composition. We suggest that this may also apply to other aromatic plants common in Mediterranean vegetation. Thymus vulgaris produce monoterpenes as the main constituent of its aromatic oil. It has a genetic polymorphism for monoterpene production, and the different monoterpenes vary in their allelopathic properties. Our finding shows that thyme increases species richness both locally and at the community level by creating a mosaic of thyme-modified and unmodified microsites differing in richness and composition. We suggest that this may also apply to other aromatic plants common in Mediterranean vegetation.

The clonal macrophyte Scirpus maritimus (Cyperaceae) propagates locally by rhizomes and reproduces sexually by achenes. The purpose of this paper was to examine whether in size-limited habitats in patchy and discrete marshes in two Mediterranean wetlands in southern France natural populations may suffer from a reduced maternal fecundity due to a deficit in outcross pollen. We first verified that S. maritimus suffers from a reduced fecundity when self-pollinated. At a site in the Camargue, mean fecundity (mean number of achenes per centimetre of spikelet) measured in 1995 and 1996 in seven and nine populations, respectively (surface area from 50 to 4500 m) increased significantly with population surface area in 1995 but not in 1996. In the second wetland at Roquehaute, which is composed of small ponds, fecundity was very low in all 12 local populations studied in 1996 (1.1 achenes per spikelet, SD = 1.2) and was not correlated with the population surface area (from 10 to 400 m). We performed a pollen supplementation experiment in five local populations at Roquehaute to determine whether this low fecundity may be due to a pollen limitation. A significant increase in fecundity after among-pond pollinations compared to within-pond pollinations indicated that local populations suffer from a deficit in outcross pollen, since each pond appears to contain one or a few number of clones (or incompatibility types). In S. maritimus, clonal spread may have a cost in terms of reduced fecundity in small habitats because each habitat is colonized by very few clones.

Clonal plant species can be considered as populations of interconnected ramets which are basically identical in form and function, and potentially independent from each other. Experimental studies and field observations suggest that an intra-clonal specialization of ramets with different roles (division of labour) can increase the performance of clonal systems under heterogeneous conditions. This paper explores structural and functional variation in the emergent macrophyte Scirpus maritimus, which forms ramets that specialize in three main activities: sexual reproduction, photosynthetic assimilation and vegetative growth, and reserve storage. The main question asked in this study is whether such specialization is a developmentally programmed syndrome in this species, and whether environmental conditions can alter the pattern of ramet differentiation along rhizome systems.

Many species show changes in distribution and phenotypic trait variation in response to climatic warming. Evidence of genetically based trait responses to climate change is, however, less common. Here, we detected evolutionary variation in the landscape-scale distribution of a genetically based chemical polymorphism in Mediterranean wild thyme ( Thymus vulgaris ) in association with modified extreme winter freezing events. By comparing current data on morph distribution with that observed in the early 1970s, we detected a significant increase in the proportion of morphs that are sensitive to winter freezing. This increase in frequency was observed in 17 of the 24 populations in which, since the 1970s, annual extreme winter freezing temperatures have risen above the thresholds that cause mortality of freezing-sensitive morphs. Our results provide an original example of rapid ongoing evolutionary change associated with relaxed selection (less extreme freezing events) on a local landscape scale. In species whose distribution and genetic variability are shaped by strong selection gradients, there may be little time lag associated with their ecological and evolutionary response to long-term environmental change.

Comment rendre les approches des musees de sciences naturelles encore plus efficaces pour relier les humains a la nature ? Cette contribution propose quelques pistes en explorant des domaines et des approches qui pour la plupart se situent hors des sentiers habituels de la museologie.

By affecting the number and the spatial distribution of flowering units (i.e., ramets), clonal growth can influence pollen transfer between plants and thus affect mating opportunities. In this paper I review some recent work that attests the importance of clonal growth for pollination patterns. A major aspect concerns the increase in floral display through the multiplication of flowering ramets. Although large floral displays can enhance pollinator attraction and may thus promote outcrossing, they can also increase rates of geitonogamy (i.e., pollination between flowers in the same plant). However, the latter aspect will depend on clonai architecture, a feature that greatly varies among clonal plant species. Future experimental studies and comparative analyses of rates of geitonogamy in species with clumped and intermingled distribution may allow for the evaluation of evolutionary interaction between clonal growth and floral traits that regulate mating patterns.

RATIONALE AND OBJECTIVES The response of osteosarcoma to preoperative chemotherapy was assessed using dynamic magnetic resonance imaging (MRI) processed by factor analysis of medical image sequences (FAMIS). METHODS Forty-nine dynamic image sequences, acquired after a bolus injection of gadolinium in 10 patients, were processed by FAMIS: FAMIS is a means whereby physiologic contrast enhancement kinetics, called factors, and their spatial distribution, termed factor images, are estimated. Tumor volumes were measured on static MRIs, and factor images were compared with histologic maps of the resected specimens. RESULTS A substantial increase in tumor volume reflected a poor response to chemotherapy. Viable tumor was precisely depicted by the early vascular factor image, reflecting rapid uptake by tumor vessels. This early uptake disappeared in all five patients who responded to chemotherapy, whereas it persisted in four of five nonresponders. CONCLUSION FAMIS of dynamic MRI is proposed as a possible means of predicting the response of osteosarcoma to chemotherapy.

The placentation of the inferior ovary of the female flower of Begonia horticola Irmscher (section Tetraphila) is mostly axile with the upper part parietal. A study of the vascular organisation and of the organogenesis of this species allows us to better understand the transition from axile to parietal placentation observed in other Begoniaceae, from both morphological and evolutionary points of view. The anatomy of the mature female flower is similar to that of other Begonia species. Anatomical sections and scanning electron microscopy of young developmental stages show that the inferior ovary grows underneath the perianth primordia. The two types of placentation are established early. The axile part develops from an axial meristem, while the parietal placentas are formed by the development of septa towards the inside of the cavity. It is however impossible to draw a clear boundary between the two tissues. The present data do not allow us to infer the evolutionary status of placentation types in Begonia.

The pistillate flower organogenesis of Begonia dregei Otto Dietr. (section Augustia) and Hillebrandia sandwicensis Oliver is described. Vascular anatomy and scanning electron microscopy show that the inferior ovary of B. dregei develops below the perianth, whereas the semi-inferior ovary of H. sandwicensis grows both above and below the insertion level of the perianth. A developmental study of both species showed that placental tissues have a mixed nature: parietal placentae develop from the ovary wall, whereas axile placentae are derived from the floral apex, with a gradual transition zone between the two tissues. Depending on the rate of growth of the two placental regions, the ovary becomes mostly axile or parietal, all intermediates being possible. Our study does not allow us to determine unambiguously which of the two types of placentation is the most primitive. Also, it is impossible to clearly ascertain the evolutionary status of the semi-inferior ovary of H. sandwicensis. However, ontogenetic results allowed us to shed new light on the nature of the ovary wall in Begonia. One may hypothesize that it is an intermediate structure between axial and appendicular organs, difficult to compare directly with a set of fused carpels and perianth parts, as postulated by the classical theory of the flower.

The Cetacean bone artifact described in this paper is the result of excavations carried out in La Madeleine (Tursac, Dordogne) under the direction of D. Peyrony, between 1910-1913. It was discovered in the middle layer (“couche moyenne”) of the stratigraphy described by Capitan and Peyrony and subsequently attributed to the “Magdalenian V” by H. Breuil (i.e the beginning of the Upper Magdalenian). This layer corresponds to layers C25 to C20 of the stratigraphy established later by J.-M. Bouvier. Two radiocarbon dates are currently available (C21: 12750 ± 240 BP, Ly 920; and C25: 13070 ± 190 BP, Ly 921). The artifact was recently identified as Cetacean bone during an integrated study of the bones and reindeer antlers kept at the Musée National de Préhistoire (Peyrony and Bouvier collections). It is a fully worked object, elongated in shape (129 X 13.2 X 12.8 mm; 18.6 g) with straight outline and profile, a circular cross-section and parallel sides. It is interpreted as a mesio-proximal fragment of projectile point. Collagen peptide mass fingerprinting (PMF) was applied to taxonomically identify the bone artefact, as a part of the PaleoCet project. Also known as ZooMS, collagen PMF discriminates taxonomic groups based on differences in the collagen protein sequence observed through Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The bone subsamples from the exterior and interior of the artifact produced similar MALDI-TOF spectra, both of which could be confidently identified as gray whale (Eschrichtius robustus). The artifact from La Madeleine is the first evidence of the presence of this species in Atlantic waters at the end of MIS2, suggesting continuity between the Pleistocene and Holocene populations of this species. Moreover, to our knowledge, this gray whale bone artifact represents the oldest identified gray whale in an archaeological context, thus first witness of the millennia-old interactions between humans and this highly coastal whale species. The manufacturing of the La Madeleine artifact on the Basque coast, followed by its circulation through the western Pyrenees and then towards the north at the east of Landes and Gironde up to Périgord (a travel distance of roughly 350 km), might be the most plausible route taken by this artifact to reach La Madeleine. L’artefact en os de cétacé décrit dans cet article provient des fouilles effectuées entre 1910 et 1913 à La Madeleine (Tursac, Dordogne) sous la direction de D. Peyrony. Il a été découvert dans la couche moyenne de la stratigraphie décrite par Capitan et Peyrony («Magdalenien V» de H. Breuil, c’est-à-dire le début du Magdalénien supérieur), et qui correspond aux couches C25 à C20 de la stratigraphie établie ultérieurement par J.-M. Bouvier. Deux dates radiocarbone sont actuellement disponibles (C21: 12750 ± 240 BP, Ly 920 ; et C25: 13070 ± 190 BP, Ly 921). La pièce a récemment été identifiée comme os de cétacé lors d’une étude intégrée des os et bois de rennes conservés au Musée national de Préhistoire (collections Peyrony et Bouvier). Il s’agit d’un objet entièrement façonné, de forme allongée (longueur X largeur X épaisseur : 129 X 13,2 X 12,8 mm ; masse 18,6 g) avec un contour et un profil droits, une section circulaire et des bords parallèles. Il est interprété comme un fragment mésio-proximal de pointe de projectile. Dans le cadre du projet PaleoCet, l’identification taxinomique de l’artefact osseux a fait l’objet d’une empreinte peptidique de masse de collagène (PMF). Aussi connu sous le nom de ZooMS, le collagène PMF discrimine les groupes taxinomiques en fonction des différences dans la séquence protéique du collagène observées par spectrométrie de masse MALDI-TOF. Les sous-échantillons osseux de l’extérieur et de l’intérieur de l’objet ont produit des spectres MALDI-TOF similaires, que l’on peut rapporter à la baleine grise (Eschrichtius robustus). La pièce de La Madeleine est la première preuve de la présence de cette espèce dans les eaux atlantiques à la fin du MIS2, ce qui suggère une continuité entre les populations pléistocènes et holocènes de cette espèce. Elle constitue la plus ancienne trace de baleine grise identifiée en contexte archéologique, et est donc le plus ancien indice des interactions millénaires entre les humains et cette espèce de baleine très côtière. Une fabrication sur la côte basque, puis une circulation à travers les Pyrénées occidentales, le nord-est des Landes et la Gironde, jusqu’au Périgord (environ 350 km de trajet), pourrait être la voie la plus plausible suivie par la pièce de La Madeleine.

Protected areas are among the key elements of global biodiversity conservation strategies and aim to conserve native species, habitats and ecosystems. Globalisation has led to increased introductions of species outside their natural range. In their new environment, some of these non-native species have the potential to affect ecosystems and compete with or threaten native species. The environment in close proximity to protected areas is likely to be the stepping stone for non-native species to become established in protected areas. However, little is known about the role that protected area surroundings play in the permeability of protected areas to non-native species. In this thesis, I focused on protected areas and their surrounding belts to address the issue of permeability to non-native species. Examining protected areas in Norway, I showed that non-native species surrounding protected areas have a qualitative impact on the community of non-native species in protected areas. Moreover, the proportion of invasive species was higher in protected areas (40 %) compared to their belts (12 %). The number of non-native species in the surrounding areas also significantly determined the number of non-native species in protected areas. I have also highlighted the dynamics of colonization from the belts to the protected areas by showing that non-native species were detected in the protected areas on average several years after they were recorded in the belts. In addition, I showed in four European countries that the type of land use and land cover in the proximity and within protected areas plays a central role in the establishment of non-native species in protected areas. Anthropogenic land use and land cover around protected areas promoted the establishment of non-native species inside protected areas, regardless of the land use and land cover present in them. Finally, I investigated the colonization dynamics of Acacia dealbata, an invasive t ree species, in and around protected areas in central Portugal over the last twenty years. I showed that disturbances by fires and the loss of tree cover had a significant positive effect on the presence of the species. This thesis highlights the importance of the protected area surroundings for the colonization of non-native species. This is particularly relevant for future management strategies for non-native species in protected areas., Les aires protégées sont des éléments clés de la stratégie mondiale de conservation de la biodiversité, en visant à préserver les espèces, les habitats et les écosystèmes. La mondialisation a entraîné une augmentation des introductions d'espèces en dehors de leur aire de répartition naturelle. Dans leur nouvel environnement, certaines de ces espèces non indigènes ont le potentiel d’affecter les écosystèmes, de concurrencer ou de menacer les espèces locales. L'environnement à proximité des aires protégées est susceptible de servir de tremplin à ces espèces introduites avant qu’elles ne pénètrent dans les aires protégées. Cependant, on sait peu de choses sur le rôle que jouent les zones entourant les aires protégées dans cette dynamique de colonisation. Dans cette thèse, nous nous sommes concentrés sur les zones entourant les aires protégées pour aborder la question de la perméabilité des aires protégées aux espèces non indigènes. En étudiant les aires protégées en Norvège, nous avons montré que le pool d’espèces non indigènes présent autour des aires protégées a un impact qualitatif sur la communauté d'espèces non indigènes présentes dans les aires protégées, les espèces non indigènes envahissantes étant présentes dans une plus grande proportion dans les aires protégées (40 %) que dans leurs ceintures (12 %). Le nombre d'espèces non indigènes présentes autour des aires protégées détermine également le nombre d'espèces non indigènes présentes dans les aires protégées. Nous avons aussi mis en évidence la dynamique de la colonisation de l’extérieur vers l’intérieur des aires protégées en montrant que les espèces non indigènes étaient détectées dans les aires protégées plusieurs années après avoir été détectées autour d’elles. En outre, nous avons montré dans quatre pays européens que le type d’occupation du sol à proximité et au sein des aires protégées joue un rôle central dans l'établissement des espèces non indigènes dans les aires protégées. Ainsi, les habitats fortement anthropisés autour des aires protégées favorisent la présence d'espèces non indigènes dans les aires protégées, quel que soit le type d’occupation du sol dans ces dernières. Enfin, nous avons étudié la dynamique de colonisation d'Acacia dealbata, une espèce d'arbre non indigène envahissante au centre du Portugal, autour et dans cinq aires protégées, au cours de ces vingt dernières années. Nous avons montré que les perturbations par les incendies et la perte de couverture forestière favorisaient la présence de l'espèce. Cette thèse a mis en évidence l'importance des zones autour des aires protégées dans la colonisation de celles-ci par les espèces non indigènes. Ces résultats sont particulièrement pertinents pour les futures stratégies de gestion des espèces non indigènes dans les aires protégées.

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