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Accurate estimations of population size and space-use are critical issues, for assessing population trends and extinction risk. In this study, we applied spatially explicit capture-recapture (SECR) modelling customized for linear habitats to a three-year Capture-Mark-Recapture (CMR) monitoring of three populations of stream-dwelling Pyrenean brook newt (Calotriton asper), an endemic species of the Pyrenean mountain range. Our aim was to explore (1) spatial and temporal variation in population densities, home range size and individual detection probability during breeding season between populations and years, and (2) the influence of water temperature and flow on activity of newts. Estimates of population density range from 3044 to 4641 individuals/km of stream across the three years of the study. Linear home range along the stream was estimated to be 13.31 m from the home range centre on average over the three years. All detection probability estimates were similar, both between years and between sites, with a mean probability of 0.09, except in Fougax in 2020 where detection probability was 0.03. Activity of the Pyrenean brook newt was influenced by water temperature and flow, but these factors acted at different time scales. Overall, population densities are locally high in both populations but home range of the Pyrenean brook newt during breeding season is very small indicating a strong site attachment. The importance of water temperature and flow on activity emphasizes the sensitivity of the species to these factors that are forecasted to change in coming decades.

Zellweger et al . (Reports, 15 May 2020, p. 772) claimed that forest plant communities’ response to global warming is primarily controlled by microclimate dynamics. We show that community thermophilization is poorly explained by the underlying components of microclimate, and that global warming primarily controls the climatic lag of plant communities. Deconstructing the underlying components of microclimate provides insights for managers.

For cryptic species, designing and implementing appropriate and effective conservation strategies is often difficult due to a lack of information about their ecology and biology. Combining scientific knowledge and expert judgments may help to address this issue. The Pyrenean brook newt (Calotriton asper) is an endemic amphibian of the Pyrenees mountain range (located in Andorra, France and Spain) and is listed as a vulnerable species on the national Red List of amphibians of metropolitan France. To ascertain a thorough understanding of the species’ current status, we identified its major threats in France using both (1) scientific knowledge about the species through an extensive literature review and (2) the expert judgments of naturalists and environmental managers through semi-structured interviews. This study highlights seven key threats (climate change, diseases, species introduction and translocation, water quality, logging industry, hydraulic activity, recreational aquatic activities) with varying levels of importance depending on whether they were mentioned by experts or published in the scientific literature. Climate change appears to be the most commonly studied threat by scientists, whereas the logging industry and fish species introduction and translocation were the major threats identified by the experts. The fact that experts and scientists conduct studies at a different spatial scale (local and global, respectively) can partly explain this difference. This extensive study provides a decision support tool for the Pyrenean brook’s newt conservation and encourages the identification of consensual decisions. Given that the threats identified towards the Pyrenean brook newt are the same as those towards other endangered species in the Pyrenees, conservation measures already exist and probably benefit this species.

Conservation plans of European amphibians usually take into account: (1) species in dramatic decline due to a series of humaninduced factors, and (2) species with a narrow distribution area and/or particular ecological requirements. Salamandra lanzai belongs to the second group, being limited to the SW Alps. Furthermore, it is a high altitude amphibian, living in sites above 1200 m, and it is also a unique endemic vertebrate of the Alps. We here summarise information regarding its distribution and ecology to be interpreted for conservation. In this sense, we also provide new data regarding the age structure of a recently studied low altitude population in the Germanasca Valley. We then compare this population (exemplified as “low altitude population”) to a population living at 2200 m in the Guil Valley (example of a “high altitude population”). The knowledge obtained on these different life-history traits has allowed us to devise an age-structured model useful in identifying the main demographic parameter...

The black salamander, Salamandra lanzai, exists in isolated and fragmented populations in the Cottian Alps. To examine the degree of intra- and interpopulation divergence, mitochondrial cytochrome b sequences were obtained from samples representing all populations of S. lanzai. No genetic variation was observed either within or among populations. The presence of a single lineage suggests historical explanations closely related to Pleistocene events.

International audience; We describe the age structures of two neighbouring terrestrial salamander populations. The skeletochronological method was also used on larvae in utero and on new-born individuals. The age of adults was 8-24 years in population A, while males reached maturity at 3-5 years old and the youngest females were 6 years old in population B. Males and females from population B were also larger than those in population A. For the first time, lines of arrested growth (LAGs) were also found in the humerus of intra-uterine larvae and new-born individuals, indicating that young can spend up to 3 years in utero (population B) and up to 4 years (population A) before hatching. Growth of adults (fitted by the Bertalanffy model) also exhibited differences in growth coefficient (k) and mean asymptotic length (SVLmax) between sexes and populations. Local climatic conditions differed between the two areas of these populations and we hypothesize that the number of rainy days directly influences foraging during the short period of activity (< 3 months), leading to a delay in age at maturity, smaller length and growth rate, and increased gestation duration in the drier environment. The discussion is focused on proximate environmental influences on the variation of length and associated life-history traits in ectotherms, especially in terrestrial salamanders.

Times Cited: 3; International audience; The pattern of genetic differentiation of the endemic alpine salamander, Salamandra atra, has been studied using amplified fragment length polymorphism (AFLP) from 11 populations throughout the range of the two currently recognized subspecies, atra and aurorae. Five different primer combinations produced 706 bands and were analyzed by constructing a phylogenetic tree using NJ and principal component analysis. Significant genetic variation was revealed by AFLP between and within populations but, our results show a lack of genetic structure. AFLP markers seems to be unsuitable to investigate complex and recent diversification. (C) 2003 Elsevier Inc. All rights reserved.

International audience; This study is part of an ongoing project aiming at determining the ethnogenesis of an eastern Siberian ethnic group, the Yakuts, on the basis of archaeological excavations carried out over a period of 10 years in three regions of Yakutia: Central Yakutia, the Vilyuy River basin and the Verkhoyansk area. In this study, genetic analyses were carried out on skeletal remains from 130 individuals of unknown ancestry dated mainly from the fifteenth to the nineteenth century AD. Kinship studies were conducted using sets of commercially available autosomal and Y-chromosomal short tandem repeats (STRs) along with hypervariable region I sequences of the mitochondrial DNA. An unexpected and intriguing finding of this work was that the uniparental marker systems did not always corroborate results from autosomal DNA analyses; in some cases, false-positive relationships were observed. These discrepancies revealed that 15 autosomal STR loci are not sufficient to discriminate between first degree relatives and more distantly related individuals in our ancient Yakut sample. The Y-STR analyses led to similar conclusions, because the current Y-STR panels provided the limited resolution of the paternal lineages.

Study, on the basis of 162 characters from 179 perfectly preserved frozen burials, of the cultural evolution of the settlement of Yakutia from the 16th century to the 19th century. The Yakuts, people from north-eastern Sibe- ria, Turkic speaking, cattle and horse breeders, are surrounded by Siberian speaking people, reindeer herders. Divided into several tribes before the Russian colonization, they will experience in contact with the Russians a "golden age" before being assimilated into the Russian Orthodox culture in the 19th century. Their frozen tombs, with intact cultural and biological data, together with historical data and this particular ecological context place their cultural evolution as an exceptional school case for human-environment interaction and for the human and social sciences. After a descriptive study of the characters, multivariate, descriptive and decisional studies, comparing differences between ages, sexes, lineages, periods, geographical groups, are carried out; it is followed by a phylogenetic analysis. The first analyses demonstrate the economic and religious changes linked to chronological evolution, while phylogeny provides hypotheses on cultural transmission, differentiated according to sex. A phase of synthesis allows us to confirm the southern origins of the Yakut culture, to identify its mechanisms of adaptation, then of evolution in the face of Russian colonization, and finally to recognize its modes of transmission and diffusion that have made it evolve from a traditional way of life to a Russian orthodox way of life.; Étude, sur la base de 162 caractères issus de 179 tombes gelées parfaitement conservées, de l'évolution culturelle du peuplement de la Iakoutie du XVIe siècle au XIXe siècle. Les Iakoutes sont un peuple du nord-est de la Sibérie, de langue turque, éleveurs de bovins et de chevaux, entourés de populations de langue sibérienne, éleveurs de rennes. Dispersés en plusieurs tribus avant la colonisation russe, ils vont connaître au contact des Russes un "âge d'or" avant d'être assimilés à la culture russe orthodoxe au XIXe siècle. Leurs tombes gelées, avec des données cultuelles et biologiques intactes, jointes aux données historiques et à ce contexte écologique particulier, font de leur évolution culturelle un cas d'école exceptionnel pour l'interaction homme/milieu et pour les sciences humaines et sociales. Après une étude descriptive des caractères, des études multivariées, descriptives et décisionnelles, confrontent les différences entre âges, sexes, lignées, périodes et en- sembles géographiques ; elles sont confrontées ensuite à une analyse phylogénétique. Les premières analyses démontrent les changements économiques et religieux liés à l'évolution chronologique tandis que la phylogénie fournit des hypothèses sur la transmission culturelle, différenciée selon le sexe. Une phase de synthèse permet de confirmer la fondation méridionale de la culture iakoute, identifier ses mécanismes d'adaptations, puis d'évolutions face à la colonisation russe et enfin de reconnaître ses modes de transmissions et de diffusion qui l'ont fait évoluer d'un mode de vie traditionnel à un mode de vie orthodoxe russe.

Study, on the basis of 162 characters from 179 perfectly preserved frozen burials, of the cultural evolution of the settlement of Yakutia from the 16th century to the 19th century. The Yakuts, people from north-eastern Sibe- ria, Turkic speaking, cattle and horse breeders, are surrounded by Siberian speaking people, reindeer herders. Divided into several tribes before the Russian colonization, they will experience in contact with the Russians a "golden age" before being assimilated into the Russian Orthodox culture in the 19th century. Their frozen tombs, with intact cultural and biological data, together with historical data and this particular ecological context place their cultural evolution as an exceptional school case for human-environment interaction and for the human and social sciences. After a descriptive study of the characters, multivariate, descriptive and decisional studies, comparing differences between ages, sexes, lineages, periods, geographical groups, are carried out; it is followed by a phylogenetic analysis. The first analyses demonstrate the economic and religious changes linked to chronological evolution, while phylogeny provides hypotheses on cultural transmission, differentiated according to sex. A phase of synthesis allows us to confirm the southern origins of the Yakut culture, to identify its mechanisms of adaptation, then of evolution in the face of Russian colonization, and finally to recognize its modes of transmission and diffusion that have made it evolve from a traditional way of life to a Russian orthodox way of life.; Étude, sur la base de 162 caractères issus de 179 tombes gelées parfaitement conservées, de l'évolution culturelle du peuplement de la Iakoutie du XVIe siècle au XIXe siècle. Les Iakoutes sont un peuple du nord-est de la Sibérie, de langue turque, éleveurs de bovins et de chevaux, entourés de populations de langue sibérienne, éleveurs de rennes. Dispersés en plusieurs tribus avant la colonisation russe, ils vont connaître au contact des Russes un "âge d'or" avant d'être assimilés à la culture russe orthodoxe au XIXe siècle. Leurs tombes gelées, avec des données cultuelles et biologiques intactes, jointes aux données historiques et à ce contexte écologique particulier, font de leur évolution culturelle un cas d'école exceptionnel pour l'interaction homme/milieu et pour les sciences humaines et sociales. Après une étude descriptive des caractères, des études multivariées, descriptives et décisionnelles, confrontent les différences entre âges, sexes, lignées, périodes et en- sembles géographiques ; elles sont confrontées ensuite à une analyse phylogénétique. Les premières analyses démontrent les changements économiques et religieux liés à l'évolution chronologique tandis que la phylogénie fournit des hypothèses sur la transmission culturelle, différenciée selon le sexe. Une phase de synthèse permet de confirmer la fondation méridionale de la culture iakoute, identifier ses mécanismes d'adaptations, puis d'évolutions face à la colonisation russe et enfin de reconnaître ses modes de transmissions et de diffusion qui l'ont fait évoluer d'un mode de vie traditionnel à un mode de vie orthodoxe russe.