The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability...The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability involves the role of atmospheric dynamics, linked in particular to the Saharan Heat Low (SHL). This article addresses this question by comparing the sets of preindustrial control and historical simulation data from climate models carried out in the framework of the CMIP5 project and observations data over the 20<sup>th</sup> century. Through multivariate statistical analyses, it was established that decadal modes of ocean variability and decadal variability of Saharan atmospheric dynamics significantly influence decadal variability of monsoon precipitation. These results also suggest the existence of external anthropogenic forcing, which is superimposed on the decadal natural variability inducing an intensification of the signal in the historical simulations compared to preindustrial control simulations. We have also shown that decadal rainfall variability in the Sahel, once the influence of oceanic modes has been eliminated, appears to be driven mainly by the activity of the Arabian Heat Low (AHL) in the central Sahel, and by the structure of the meridional temperature gradient over the inter-tropical Atlantic in the western Sahel.展开更多
We report on an experiment performed at the FLASH2 free-electron laser(FEL)aimed at producing warm dense matter via soft x-ray isochoric heating.In the experiment,we focus on study of the ions emitted during the soft ...We report on an experiment performed at the FLASH2 free-electron laser(FEL)aimed at producing warm dense matter via soft x-ray isochoric heating.In the experiment,we focus on study of the ions emitted during the soft x-ray ablation process using time-of-flight electron multipliers and a shifted Maxwell–Boltzmann velocity distribution model.We find that most emitted ions are thermal,but that some impurities chemisorbed on the target surface,such as protons,are accelerated by the electrostatic field created in the plasma by escaped electrons.The morphology of the complex crater structure indicates the presence of several ion groups with varying temperatures.We find that the ion sound velocity is controlled by the ion temperature and show how the ion yield depends on the FEL radiation attenuation length in different materials.展开更多
The Honghe Hani Rice Terraces of Yunnan Province have become a national emblem for China and a UNESCO World Heritage Site,but some are beginning to crumble.This research attempts to address why this is happening and w...The Honghe Hani Rice Terraces of Yunnan Province have become a national emblem for China and a UNESCO World Heritage Site,but some are beginning to crumble.This research attempts to address why this is happening and what can be done about it.Previous work has failed to adequately address the possible shortcomings of recently introduced seed and water management technologies,their particular effect on rice terraces and the people who depend upon them.In an effort to better understand the issue,field observation was triangulated with in-depth interviews with local people,and the examination of scientific literature.To do this,the authors spent time in China with a translator in a key village known to be first in the area to truly succeed in carving the rice terraces and in making the mountain slope irrigation system required actually working.Results validated by experts in each field indicate that while the new seed and technologies do save water and improve lives,paired with migration,they may also be threatening the long-term viability of rice terracing in the region.The authors conclude that an integrated approach is needed and put forward a strategic blueprint to reinforce ecological,social and economic longevity.They also call for more research into the applicability of these resilience measures in other hybrid rice terracing regions,such as in the Philippines and Vietnam.展开更多
Inbreeding negatively affects various life-history traits, with inbred individuals typically having lower fit- ness than outbred individuals （=inbreeding depression）. Inbreeding depression is often emphasized under ...Inbreeding negatively affects various life-history traits, with inbred individuals typically having lower fit- ness than outbred individuals （=inbreeding depression）. Inbreeding depression is often emphasized under environmental stress, but the underlying mechanisms and potential long-lasting consequences of such inbreeding-environment interactions remain poorly understood. Here, we hypothesize that inbreeding-environment interactions that occur early in life have long-term physiological effects, in partic- ular on the adult oxidative balance. We applied a unique experimental design to manipulate early life conditions of inbred and outbred songbirds （Serinus canaria） that allowed us to separate prenatal and postnatal components of early life conditions and their respective importance in inbreeding-environment interactions. We measured a wide variety of markers of oxidative status in adulthood, resulting in a com- prehensive account for oxidative balance. Using a Bayesian approach with Markov chain Monte Carlo, we found clear sex-specific effects and we also found only in females small yet significant long-term effects of inbreeding-environment interactions on adult oxidative balance. Postnatal components of early life conditions were most persuasively reflected on adult oxidative balance, with inbred females that experienced disadvantageous postnatal conditions upregulating enzymatic antioxidants in adulthood. Our study provides some evidence that adult oxidative balance can reflect inbreeding-environment inter- actions early in life, but given the rather small effects that were limited to females, we conclude that oxida- tive stress miaht have a limited role as mechanism underlvina inhre.e.dina-envirnnme.nt inte.raetinn.q_展开更多
Background: The Cambodian Tailorbird(Orthotomus chaktomuk) was one of the most recent major ornithological discoveries in South-east Asia as it originated from lowland seasonally flooded scrub within the densely inhab...Background: The Cambodian Tailorbird(Orthotomus chaktomuk) was one of the most recent major ornithological discoveries in South-east Asia as it originated from lowland seasonally flooded scrub within the densely inhabited floodplain around the Tonle Sap, Mekong and Bassac rivers(Cambodia). The Cambodian Tailorbird is sister to the Dark-necked Tailorbird(O. atrogularis) with very limited genetics and biometric differentiation. Between 2004 and 2012, evidences of a new population of Ashy Tailorbird(O. ruficeps) in SE Cambodia/Vietnam accumulated but no museum specimens were ever reported. The Ashy Tailorbird currently consists of eight subspecies among which the closest geographical populations, O. r. cineraceus(SE Burma to Malay Peninsula, Sumatra, Bangka and Belitung) and O. r. borneoensis(Borneo), are allopatric. Subspecific identification of the Cambodian Ashy Tailorbirds individuals was not possible because of the limited differences in plumage among subspecies.Methods: We inspected the Orthotomus ruficeps specimens housed at the Museum National d'Histoire Naturelle(Paris) and discovered five specimens of O. ruficeps collected by Louis Rodolphe Germain in ‘Cochinchina'(corresponding to southern Vietnam) during the nineteenth century. We sequenced one mitochondrial locus and gathered biometric data from these specimens and compared them with other Orthotomus lineages.Results: The Ashy Tailord population from SE Cambodia and Vietnam is distinct from the two geographically close subspecies O. r. borneoensis(1.7%) and O. r. cineraceus(1.3%). O. chaktomuk is nested within O. atrogularis in the mitochondrial gene tree. The SE Cambodia/Vietnam population of O. ruficeps is distinct from the two other subspecies in bill shape.Conclusion: Our study described the biometric and molecular distinctiveness of a recently re-discovered population of Ashy Tailord in SE Cambodia and Vietnam and suggests that this population constitutes an independent evolutionary lineage that we describe here as a new subspecies. The newly described Cambodian Tailorbird is nested within the Dark-necked Tailorbird and the genetic divergence is much lower than initially described(0.4-0.7% vs 1.1-1.4%).展开更多
This study investigated the systematics of the megophryid genus Scutiger from eastern and western Nepal using molecular and morphological data. Our results support two divergent lineages, one of which has nuptial spin...This study investigated the systematics of the megophryid genus Scutiger from eastern and western Nepal using molecular and morphological data. Our results support two divergent lineages, one of which has nuptial spines on the dorsal surface of the first three fingers while the other has spines only on the dorsal surface of the first two fingers. The Ghunsa lineage from eastern Nepal shows significant morphological and molecular differences to other species of genus Scutiger and is here described as a new species. Based on the molecular analysis, the Muktinath lineage from western Nepal is confirmed to be Scutiger boulengeri and represents a species complex widespread throughout the Himalayan region. The newly described taxon is endemic to the eastern Himalayas and currently known only from the Ghunsa valley, Taplejung district, Nepal.展开更多
The vast diversity of morphologies,body size,and lifestyles of snakes represents an important source of information that can be used to derive bio-inspired robots through a biology-push and pull process.An understandi...The vast diversity of morphologies,body size,and lifestyles of snakes represents an important source of information that can be used to derive bio-inspired robots through a biology-push and pull process.An understanding of the detailed kinematics of swimming snakes is a fundamental prerequisite to conceive and design bio-inspired aquatic snake robots.However,only limited information is available on the kinematics of swimming snake.Fast and accurate methods are needed to fill this knowledge gap.In the present paper,three existing methods were compared to test their capacity to characterize the kinematics of swimming snakes.(1)Marker tracking(Deftac),(2)Markerless pose estimation(DeepLabCut),and(3)Motion capture were considered.(4)We also designed and tested an automatic video processing method.All methods provided different albeit complementary data sets;they also involved different technical issues in terms of experimental conditions,snake manipulation,or processing resources.Marker tracking provided accurate data that can be used to calibrate other methods.Motion capture posed technical difficulties but can provide limited 3D data.Markerless pose estimation required deep learning(thus time)but was efficient to extract the data under various experimental conditions.Finally,automatic video processing was particularly efficient to extract a wide range of data useful for both biology and robotics but required a specific experimental setting.展开更多
The European abalone Haliotis tuberculata is of economical importance in Europe, and recently in France where most of the consumed abalones remained wild animals fished on the coast. Recently, the creation of hatcheri...The European abalone Haliotis tuberculata is of economical importance in Europe, and recently in France where most of the consumed abalones remained wild animals fished on the coast. Recently, the creation of hatcheries allowed the production of cultured animals, and aquaculture is in progress. To optimize selective breeding programs, different studies were performed on adults and on their progenies. First, ten adult families, assumed to be bi-parental and produced in 2007 were analyzed. As these families were developed at the beginning of the hatchery production, the parentage of the individual necessitated to be tested. The progenies parentage assignment was done by using eight microsatellite DNA loci. In fine, the heritability was estimated from the analysis of variance of seven full-sib families which include from 23 to 27 progenies. Heritability estimate was the higher for length, width and weight (0.37, 0.29 and 0.40 respectively). A high correlation was also shown between these heritable traits which can be useful during animal breeding. Shell color traits were also analyzed, using image treatment procedure. Two traits were selected according to the global color of the shell: red color and hue. The distribution of these traits evidenced a polygenic genetic control of shell color and measure of heritability evidenced a high to medium value for red color (Cr) and Hue(H) (0.33 and 0.20 respectively). No correlation was shown between growth and this parameter. In a second time, juveniles families produced in 2010 were studied from parents issued of the first selection. A correlation between size and density at juvenile stage was established but a statistical analysis demonstrated, by using density as co-variable a significant effect of family on size. In these conditions, growth is highly heritable (0.74). This study is a first step toward the use of genetic markers for selection, but also a step toward the breeding improvement of European abalone.展开更多
In biodiversity management, spatio-temporal heterogeneity is important to consider conserving high levels of habitat diversity and ecosystems. In this study, we investigated the relationship between landscape spatio-t...In biodiversity management, spatio-temporal heterogeneity is important to consider conserving high levels of habitat diversity and ecosystems. In this study, we investigated the relationship between landscape spatio-temporal heterogeneity and biodiversity in a mosaic-landscape, located in the Fontainebleau forest (France). The diversity of successional stages along a gradient from heathland to forest as well as the persistence of Calluna vulgaris (L.) Hull in different forest stands was examined in order to find how the numerous patches of European Heathland habitat embedded in this area should be maintained. The results indicated that in the areas of high spatio-temporal heterogeneity, a general increase is observed in species richness, in particular for vascular plants, bryophytes and carabids. C. vulgaris persisted in coniferous stands and young mixed stand but decreased under deciduous trees and old mixed stands. The Ellenberg’s values for light, nutrients and acidity, show the persistence of favorable enviromental conditions for heathland vegetation under coniferous stands and young mixed stands. These results enable us to offer recommendations to better manage mosaic-landscape biodiversity, and in particular, the heathland semi-natural habitats in the Fontainebleau forest and elsewhere in Europe.展开更多
It is well known that age influences organism mobility. This was demonstrated in vertebrates （such as mammals and birds） but has been less studied in invertebrates with the exception of Drosophila and the nematode C...It is well known that age influences organism mobility. This was demonstrated in vertebrates （such as mammals and birds） but has been less studied in invertebrates with the exception of Drosophila and the nematode Caenorhabditis elegans. Here we studied the influence of age on the mobility of the orb-weaving spider Zygiella x-notata during web construction. The orb-web is a good model because it has a characteristic geometrical structure and video tracking can be used to easily follow the spider＇s movements during web building. We investigated the influence of age （specifically chronological age, life span, and time till death） on different parameters of spider mobility during the construction of the capture spiral （distance traveled, duration of construction, spider velocity, spider movement, and spider inactivity） with a generalized linear model （GLM） procedure adjusted for the spider mass. The re- sults showed that neither chronological age, nor life span affected the mobility parameters. However, when the time till death decreased, there was a decrease in the distance traveled, the duration of the construction of the capture spiral, and the spider movement. The spider velocity and the time of inactivity were not affected. These results could be correlated with a decrease in the length of the silky thread deposited for the construction of the capture spiral. Spiders with a shorter time till death built smaller web using less silk. Thus, our study suggests strongly that time till death affects spider mobility during web construction but not the chronological age and thus may be a good indicator of senescence.展开更多
Background:The European Kingfisher(Alcedo atthis)is a small plunge-diving bird,today considered a species of conservation concern in Europe given its rapid population decline observed across the continent.We implement...Background:The European Kingfisher(Alcedo atthis)is a small plunge-diving bird,today considered a species of conservation concern in Europe given its rapid population decline observed across the continent.We implemented a pilot study aimed at providing first data allowing to:(1)assess home range features of the European Kingfisher for populations with unevenly distributed feeding habitats;(2)define conservation implications for habitats exploited by such populations;and(3)evaluate possibilities for developing GPS tracking schemes dedicated to home range stud-ies for this species that could be possibly applied to other small plunge-diving birds.Methods:In 2018 and 2019,we equipped 16 breeding European Kingfishers sampled within the marshes of the Gironde Estuary(France),with miniaturized and waterproof GPS archival tags deployed with leg-loop harnesses(total equipment mass=1.4 g;average bird mass=40.18±1.12 g).Results:On average,we collected 35.31±6.66 locations usable for analyses,without a significant effect on bird body condition(n=13 tags retrieved).Data analyses highlighted rather limited home ranges exploited by birds(aver-age=2.50±0.55 ha),composed on average by 2.78±0.40 location nuclei.Our results also underscore:(1)a rather important home range fragmentation index(0.36±0.08);and(2)the use by birds of different types of small wetlands(wet ditches,small ponds or small waterholes),often exploited in addition to habitats encompassing nest locations.Conclusions:Our study reveals interesting GPS tracking possibilities for small plunge-diving birds such as the European Kingfisher.For this species,today classified as vulnerable in Europe,our results underline the importance of developing conservation and ecological restoration policies for wetland networks that would integrate small wet-lands particularly sensitive to global change.展开更多
Background: Genetically engineered animals are essential for gaining a proper understanding of the disease mechanisms of cystic fibrosis(CF). The rat is a relevant laboratory model for CF because of its zootechnical c...Background: Genetically engineered animals are essential for gaining a proper understanding of the disease mechanisms of cystic fibrosis(CF). The rat is a relevant laboratory model for CF because of its zootechnical capacity, size, and airway characteristics, including the presence of submucosal glands.Methods: We describe the generation of a CF rat model(F508 del) homozygous for the p.Phe508 del mutation in the transmembrane conductance regulator(Cftr) gene. This model was compared to new Cftr-/-rats(CFTR KO). Target organs in CF were examined by histological staining of tissue sections and tooth enamel was quantified by micro-computed tomography. The activity of CFTR was evaluated by nasal potential difference(NPD) and short-circuit current measurements. The effect of VX-809 and VX-770 was analyzed on nasal epithelial primary cell cultures from F508 del rats.Results: Both newborn F508 del and Knock out(KO) animals developed intestinal obstruction that could be partly compensated by special diet combined with an osmotic laxative. The two rat models exhibited CF phenotypic anomalies such as vas deferens agenesis and tooth enamel defects. Histology of the intestine, pancreas, liver, and lungs was normal. Absence of CFTR function in KO rats was confirmed ex vivo by short-circuit current measurements on colon mucosae and in vivo by NPD, whereas residual CFTR activity was observed in F508 del rats. Exposure of F508 del CFTR nasal primary cultures to a combination of VX-809 and VX-770 improved CFTR-mediated Cl-transport.Conclusions: The F508 del rats reproduce the phenotypes observed in CFTR KO animals and represent a novel resource to advance the development of CF therapeutics.展开更多
A method of retrieving PM10 particles concentrations at the ground level from AOT (Aerosol Optical Thickness) measurements is presented. It uses data obtained among five years during 2003 to 2007 summers in the Lille ...A method of retrieving PM10 particles concentrations at the ground level from AOT (Aerosol Optical Thickness) measurements is presented. It uses data obtained among five years during 2003 to 2007 summers in the Lille region (northern France). As PM10 concentration strongly depends on meteorological variables, we clustered the meteorological situations provided by the MM5 meteorological model forced at the lateral boundaries by the operational NCEP model in eight classes (local weather types) for which a robust statistical relationship between AOT and PM10 was found. The meteorological situations were defined by the hourly vertical profiles of temperature and (zonal and meridian) wind components. The clustering of the weather types were obtained by a self-organizing map (SOM) followed by a hierarchical ascending classification (HAC). We were then able to retrieve the PM10 at the surface from the AERONET AOT measurements for each weather type by doing non linear regressions with dedicated SOMs. The method is general and could be extended to other regions. We analyzed the strong pollution event that occurred during August 2003 heat wave. Comparison of the results from our method with the output of the CHIMERE chemical-transport model showed the interest to tentatively combine these two pieces of information to improve particle pollution alert.展开更多
Many animal species migrate over long distances, but the physiological challenges of migration are poorly understood. It has recently been suggested that increased molecular oxidative damage might be one important cha...Many animal species migrate over long distances, but the physiological challenges of migration are poorly understood. It has recently been suggested that increased molecular oxidative damage might be one important challenge for migratory animals. We tested the hypothesis that autumn migration imposes an oxidative challenge to bats by comparing values of 4 blood-based markers of oxidative status (oxidative damage and both enzymatic and nonenzymatic antioxidants) between Nathusius' bats Pipistrellus nathusii that were caught during migration flights with those measured in conspecifics after resting for 18 or 24 h. Experiments were carried out at Pape Ornithological Station in Pape (Latvia) in 2016 and 2017. Our results show that flying bats have a blood oxidative status different from that of resting bats due to higher oxidative damage and different expression of both non enzymatic and enzymatic antioxidants (glutathione peroxidase). The differences in oxidative status markers varied betwee n sampli ng years and were in depende nt from in dividual body con dition or sex. Our work provides evidence that migratory flight might impose acute oxidative stress to bats and that resting helps animals to recover from oxidative damage accrued en route. Our data suggest that migrating bats and birds might share similar strategies of mitigating and recovering from oxidative stress.展开更多
文摘The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability involves the role of atmospheric dynamics, linked in particular to the Saharan Heat Low (SHL). This article addresses this question by comparing the sets of preindustrial control and historical simulation data from climate models carried out in the framework of the CMIP5 project and observations data over the 20<sup>th</sup> century. Through multivariate statistical analyses, it was established that decadal modes of ocean variability and decadal variability of Saharan atmospheric dynamics significantly influence decadal variability of monsoon precipitation. These results also suggest the existence of external anthropogenic forcing, which is superimposed on the decadal natural variability inducing an intensification of the signal in the historical simulations compared to preindustrial control simulations. We have also shown that decadal rainfall variability in the Sahel, once the influence of oceanic modes has been eliminated, appears to be driven mainly by the activity of the Arabian Heat Low (AHL) in the central Sahel, and by the structure of the meridional temperature gradient over the inter-tropical Atlantic in the western Sahel.
文摘We report on an experiment performed at the FLASH2 free-electron laser(FEL)aimed at producing warm dense matter via soft x-ray isochoric heating.In the experiment,we focus on study of the ions emitted during the soft x-ray ablation process using time-of-flight electron multipliers and a shifted Maxwell–Boltzmann velocity distribution model.We find that most emitted ions are thermal,but that some impurities chemisorbed on the target surface,such as protons,are accelerated by the electrostatic field created in the plasma by escaped electrons.The morphology of the complex crater structure indicates the presence of several ion groups with varying temperatures.We find that the ion sound velocity is controlled by the ion temperature and show how the ion yield depends on the FEL radiation attenuation length in different materials.
文摘The Honghe Hani Rice Terraces of Yunnan Province have become a national emblem for China and a UNESCO World Heritage Site,but some are beginning to crumble.This research attempts to address why this is happening and what can be done about it.Previous work has failed to adequately address the possible shortcomings of recently introduced seed and water management technologies,their particular effect on rice terraces and the people who depend upon them.In an effort to better understand the issue,field observation was triangulated with in-depth interviews with local people,and the examination of scientific literature.To do this,the authors spent time in China with a translator in a key village known to be first in the area to truly succeed in carving the rice terraces and in making the mountain slope irrigation system required actually working.Results validated by experts in each field indicate that while the new seed and technologies do save water and improve lives,paired with migration,they may also be threatening the long-term viability of rice terracing in the region.The authors conclude that an integrated approach is needed and put forward a strategic blueprint to reinforce ecological,social and economic longevity.They also call for more research into the applicability of these resilience measures in other hybrid rice terracing regions,such as in the Philippines and Vietnam.
文摘Inbreeding negatively affects various life-history traits, with inbred individuals typically having lower fit- ness than outbred individuals （=inbreeding depression）. Inbreeding depression is often emphasized under environmental stress, but the underlying mechanisms and potential long-lasting consequences of such inbreeding-environment interactions remain poorly understood. Here, we hypothesize that inbreeding-environment interactions that occur early in life have long-term physiological effects, in partic- ular on the adult oxidative balance. We applied a unique experimental design to manipulate early life conditions of inbred and outbred songbirds （Serinus canaria） that allowed us to separate prenatal and postnatal components of early life conditions and their respective importance in inbreeding-environment interactions. We measured a wide variety of markers of oxidative status in adulthood, resulting in a com- prehensive account for oxidative balance. Using a Bayesian approach with Markov chain Monte Carlo, we found clear sex-specific effects and we also found only in females small yet significant long-term effects of inbreeding-environment interactions on adult oxidative balance. Postnatal components of early life conditions were most persuasively reflected on adult oxidative balance, with inbred females that experienced disadvantageous postnatal conditions upregulating enzymatic antioxidants in adulthood. Our study provides some evidence that adult oxidative balance can reflect inbreeding-environment inter- actions early in life, but given the rather small effects that were limited to females, we conclude that oxida- tive stress miaht have a limited role as mechanism underlvina inhre.e.dina-envirnnme.nt inte.raetinn.q_
基金support by a Synthesys grant made available to J.Fuchs by the European Community-Research Infrastructure Action under the FP6 Structuring the European Research Area Program(SE-TAF-7153)
文摘Background: The Cambodian Tailorbird(Orthotomus chaktomuk) was one of the most recent major ornithological discoveries in South-east Asia as it originated from lowland seasonally flooded scrub within the densely inhabited floodplain around the Tonle Sap, Mekong and Bassac rivers(Cambodia). The Cambodian Tailorbird is sister to the Dark-necked Tailorbird(O. atrogularis) with very limited genetics and biometric differentiation. Between 2004 and 2012, evidences of a new population of Ashy Tailorbird(O. ruficeps) in SE Cambodia/Vietnam accumulated but no museum specimens were ever reported. The Ashy Tailorbird currently consists of eight subspecies among which the closest geographical populations, O. r. cineraceus(SE Burma to Malay Peninsula, Sumatra, Bangka and Belitung) and O. r. borneoensis(Borneo), are allopatric. Subspecific identification of the Cambodian Ashy Tailorbirds individuals was not possible because of the limited differences in plumage among subspecies.Methods: We inspected the Orthotomus ruficeps specimens housed at the Museum National d'Histoire Naturelle(Paris) and discovered five specimens of O. ruficeps collected by Louis Rodolphe Germain in ‘Cochinchina'(corresponding to southern Vietnam) during the nineteenth century. We sequenced one mitochondrial locus and gathered biometric data from these specimens and compared them with other Orthotomus lineages.Results: The Ashy Tailord population from SE Cambodia and Vietnam is distinct from the two geographically close subspecies O. r. borneoensis(1.7%) and O. r. cineraceus(1.3%). O. chaktomuk is nested within O. atrogularis in the mitochondrial gene tree. The SE Cambodia/Vietnam population of O. ruficeps is distinct from the two other subspecies in bill shape.Conclusion: Our study described the biometric and molecular distinctiveness of a recently re-discovered population of Ashy Tailord in SE Cambodia and Vietnam and suggests that this population constitutes an independent evolutionary lineage that we describe here as a new subspecies. The newly described Cambodian Tailorbird is nested within the Dark-necked Tailorbird and the genetic divergence is much lower than initially described(0.4-0.7% vs 1.1-1.4%).
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA23080101)National Natural Sciences Foundation of China (NSFC-31471964)+1 种基金grants to Jianping Jiang and the second comprehensive science investigation of Qinghai-Tibet Plateau (QTP) (II08-T05-2017-04/06)supported by the CAS-TWAS President Fellowship and Chinese Academy of Sciences President’s International Fellowship Initiative (2018PB0016)
文摘This study investigated the systematics of the megophryid genus Scutiger from eastern and western Nepal using molecular and morphological data. Our results support two divergent lineages, one of which has nuptial spines on the dorsal surface of the first three fingers while the other has spines only on the dorsal surface of the first two fingers. The Ghunsa lineage from eastern Nepal shows significant morphological and molecular differences to other species of genus Scutiger and is here described as a new species. Based on the molecular analysis, the Muktinath lineage from western Nepal is confirmed to be Scutiger boulengeri and represents a species complex widespread throughout the Himalayan region. The newly described taxon is endemic to the eastern Himalayas and currently known only from the Ghunsa valley, Taplejung district, Nepal.
基金Agence Nationale de la recherche(Grant no.ANR-20-CE02-0010).
文摘The vast diversity of morphologies,body size,and lifestyles of snakes represents an important source of information that can be used to derive bio-inspired robots through a biology-push and pull process.An understanding of the detailed kinematics of swimming snakes is a fundamental prerequisite to conceive and design bio-inspired aquatic snake robots.However,only limited information is available on the kinematics of swimming snake.Fast and accurate methods are needed to fill this knowledge gap.In the present paper,three existing methods were compared to test their capacity to characterize the kinematics of swimming snakes.(1)Marker tracking(Deftac),(2)Markerless pose estimation(DeepLabCut),and(3)Motion capture were considered.(4)We also designed and tested an automatic video processing method.All methods provided different albeit complementary data sets;they also involved different technical issues in terms of experimental conditions,snake manipulation,or processing resources.Marker tracking provided accurate data that can be used to calibrate other methods.Motion capture posed technical difficulties but can provide limited 3D data.Markerless pose estimation required deep learning(thus time)but was efficient to extract the data under various experimental conditions.Finally,automatic video processing was particularly efficient to extract a wide range of data useful for both biology and robotics but required a specific experimental setting.
文摘The European abalone Haliotis tuberculata is of economical importance in Europe, and recently in France where most of the consumed abalones remained wild animals fished on the coast. Recently, the creation of hatcheries allowed the production of cultured animals, and aquaculture is in progress. To optimize selective breeding programs, different studies were performed on adults and on their progenies. First, ten adult families, assumed to be bi-parental and produced in 2007 were analyzed. As these families were developed at the beginning of the hatchery production, the parentage of the individual necessitated to be tested. The progenies parentage assignment was done by using eight microsatellite DNA loci. In fine, the heritability was estimated from the analysis of variance of seven full-sib families which include from 23 to 27 progenies. Heritability estimate was the higher for length, width and weight (0.37, 0.29 and 0.40 respectively). A high correlation was also shown between these heritable traits which can be useful during animal breeding. Shell color traits were also analyzed, using image treatment procedure. Two traits were selected according to the global color of the shell: red color and hue. The distribution of these traits evidenced a polygenic genetic control of shell color and measure of heritability evidenced a high to medium value for red color (Cr) and Hue(H) (0.33 and 0.20 respectively). No correlation was shown between growth and this parameter. In a second time, juveniles families produced in 2010 were studied from parents issued of the first selection. A correlation between size and density at juvenile stage was established but a statistical analysis demonstrated, by using density as co-variable a significant effect of family on size. In these conditions, growth is highly heritable (0.74). This study is a first step toward the use of genetic markers for selection, but also a step toward the breeding improvement of European abalone.
文摘In biodiversity management, spatio-temporal heterogeneity is important to consider conserving high levels of habitat diversity and ecosystems. In this study, we investigated the relationship between landscape spatio-temporal heterogeneity and biodiversity in a mosaic-landscape, located in the Fontainebleau forest (France). The diversity of successional stages along a gradient from heathland to forest as well as the persistence of Calluna vulgaris (L.) Hull in different forest stands was examined in order to find how the numerous patches of European Heathland habitat embedded in this area should be maintained. The results indicated that in the areas of high spatio-temporal heterogeneity, a general increase is observed in species richness, in particular for vascular plants, bryophytes and carabids. C. vulgaris persisted in coniferous stands and young mixed stand but decreased under deciduous trees and old mixed stands. The Ellenberg’s values for light, nutrients and acidity, show the persistence of favorable enviromental conditions for heathland vegetation under coniferous stands and young mixed stands. These results enable us to offer recommendations to better manage mosaic-landscape biodiversity, and in particular, the heathland semi-natural habitats in the Fontainebleau forest and elsewhere in Europe.
文摘It is well known that age influences organism mobility. This was demonstrated in vertebrates （such as mammals and birds） but has been less studied in invertebrates with the exception of Drosophila and the nematode Caenorhabditis elegans. Here we studied the influence of age on the mobility of the orb-weaving spider Zygiella x-notata during web construction. The orb-web is a good model because it has a characteristic geometrical structure and video tracking can be used to easily follow the spider＇s movements during web building. We investigated the influence of age （specifically chronological age, life span, and time till death） on different parameters of spider mobility during the construction of the capture spiral （distance traveled, duration of construction, spider velocity, spider movement, and spider inactivity） with a generalized linear model （GLM） procedure adjusted for the spider mass. The re- sults showed that neither chronological age, nor life span affected the mobility parameters. However, when the time till death decreased, there was a decrease in the distance traveled, the duration of the construction of the capture spiral, and the spider movement. The spider velocity and the time of inactivity were not affected. These results could be correlated with a decrease in the length of the silky thread deposited for the construction of the capture spiral. Spiders with a shorter time till death built smaller web using less silk. Thus, our study suggests strongly that time till death affects spider mobility during web construction but not the chronological age and thus may be a good indicator of senescence.
基金financial support of the Département de la Charente-Maritime
文摘Background:The European Kingfisher(Alcedo atthis)is a small plunge-diving bird,today considered a species of conservation concern in Europe given its rapid population decline observed across the continent.We implemented a pilot study aimed at providing first data allowing to:(1)assess home range features of the European Kingfisher for populations with unevenly distributed feeding habitats;(2)define conservation implications for habitats exploited by such populations;and(3)evaluate possibilities for developing GPS tracking schemes dedicated to home range stud-ies for this species that could be possibly applied to other small plunge-diving birds.Methods:In 2018 and 2019,we equipped 16 breeding European Kingfishers sampled within the marshes of the Gironde Estuary(France),with miniaturized and waterproof GPS archival tags deployed with leg-loop harnesses(total equipment mass=1.4 g;average bird mass=40.18±1.12 g).Results:On average,we collected 35.31±6.66 locations usable for analyses,without a significant effect on bird body condition(n=13 tags retrieved).Data analyses highlighted rather limited home ranges exploited by birds(aver-age=2.50±0.55 ha),composed on average by 2.78±0.40 location nuclei.Our results also underscore:(1)a rather important home range fragmentation index(0.36±0.08);and(2)the use by birds of different types of small wetlands(wet ditches,small ponds or small waterholes),often exploited in addition to habitats encompassing nest locations.Conclusions:Our study reveals interesting GPS tracking possibilities for small plunge-diving birds such as the European Kingfisher.For this species,today classified as vulnerable in Europe,our results underline the importance of developing conservation and ecological restoration policies for wetland networks that would integrate small wet-lands particularly sensitive to global change.
基金TEFOR,Grant/Award Number:RIIINSB-0014France Life Imaging,Grant/Award Number:ANR-11-INBS-0006+6 种基金Swiss Cystic Fibrosis Foundation CFCHFondation Maladies RaresInfrastructures Biologie-SantéIHU-CESTI,Grant/Award Number:ANR-10-IBHU-005IRSR Pays de la LoireVaincre la MucoviscidoseSwiss National Foundation,Grant/Award Number:310030_172909
文摘Background: Genetically engineered animals are essential for gaining a proper understanding of the disease mechanisms of cystic fibrosis(CF). The rat is a relevant laboratory model for CF because of its zootechnical capacity, size, and airway characteristics, including the presence of submucosal glands.Methods: We describe the generation of a CF rat model(F508 del) homozygous for the p.Phe508 del mutation in the transmembrane conductance regulator(Cftr) gene. This model was compared to new Cftr-/-rats(CFTR KO). Target organs in CF were examined by histological staining of tissue sections and tooth enamel was quantified by micro-computed tomography. The activity of CFTR was evaluated by nasal potential difference(NPD) and short-circuit current measurements. The effect of VX-809 and VX-770 was analyzed on nasal epithelial primary cell cultures from F508 del rats.Results: Both newborn F508 del and Knock out(KO) animals developed intestinal obstruction that could be partly compensated by special diet combined with an osmotic laxative. The two rat models exhibited CF phenotypic anomalies such as vas deferens agenesis and tooth enamel defects. Histology of the intestine, pancreas, liver, and lungs was normal. Absence of CFTR function in KO rats was confirmed ex vivo by short-circuit current measurements on colon mucosae and in vivo by NPD, whereas residual CFTR activity was observed in F508 del rats. Exposure of F508 del CFTR nasal primary cultures to a combination of VX-809 and VX-770 improved CFTR-mediated Cl-transport.Conclusions: The F508 del rats reproduce the phenotypes observed in CFTR KO animals and represent a novel resource to advance the development of CF therapeutics.
文摘A method of retrieving PM10 particles concentrations at the ground level from AOT (Aerosol Optical Thickness) measurements is presented. It uses data obtained among five years during 2003 to 2007 summers in the Lille region (northern France). As PM10 concentration strongly depends on meteorological variables, we clustered the meteorological situations provided by the MM5 meteorological model forced at the lateral boundaries by the operational NCEP model in eight classes (local weather types) for which a robust statistical relationship between AOT and PM10 was found. The meteorological situations were defined by the hourly vertical profiles of temperature and (zonal and meridian) wind components. The clustering of the weather types were obtained by a self-organizing map (SOM) followed by a hierarchical ascending classification (HAC). We were then able to retrieve the PM10 at the surface from the AERONET AOT measurements for each weather type by doing non linear regressions with dedicated SOMs. The method is general and could be extended to other regions. We analyzed the strong pollution event that occurred during August 2003 heat wave. Comparison of the results from our method with the output of the CHIMERE chemical-transport model showed the interest to tentatively combine these two pieces of information to improve particle pollution alert.
文摘Many animal species migrate over long distances, but the physiological challenges of migration are poorly understood. It has recently been suggested that increased molecular oxidative damage might be one important challenge for migratory animals. We tested the hypothesis that autumn migration imposes an oxidative challenge to bats by comparing values of 4 blood-based markers of oxidative status (oxidative damage and both enzymatic and nonenzymatic antioxidants) between Nathusius' bats Pipistrellus nathusii that were caught during migration flights with those measured in conspecifics after resting for 18 or 24 h. Experiments were carried out at Pape Ornithological Station in Pape (Latvia) in 2016 and 2017. Our results show that flying bats have a blood oxidative status different from that of resting bats due to higher oxidative damage and different expression of both non enzymatic and enzymatic antioxidants (glutathione peroxidase). The differences in oxidative status markers varied betwee n sampli ng years and were in depende nt from in dividual body con dition or sex. Our work provides evidence that migratory flight might impose acute oxidative stress to bats and that resting helps animals to recover from oxidative damage accrued en route. Our data suggest that migrating bats and birds might share similar strategies of mitigating and recovering from oxidative stress.
