Radar-Coding and Geocoding Lookup Tables for the Fusion of GIS Data and SAR images in Mountain Areas

International audienceSynthetic aperture radar (SAR) image orthorectification induces an important alteration of information due to the side-looking geometry of SAR acquisition. In high-relief areas, the difficulty is increased by the foldover effect: The images acquired with low incidence angles cannot be registered by a bijective transformation like polynomial transformations, as usually proposed by conventional software. In this letter, a simple and efficient method, fitted to geocoded data and SAR images, is introduced to propose a generic coregistration tool that takes SAR geometry into account without requiring the exact sensor model, specific parameters, and precise navigation data. This method is based on a simulated SAR image and on the computation of lookup tables (LUTs) that represent the coordinate transform from one geometry to the other. Results are presented on a high-relief area in the Alps, where satellite and airborne SAR images are used for glacier evolution monitoring. A comparison to other sensor-independent approaches has been performed, showing that the proposed approach performs better in mountain areas. The resulting LUTs allow merging SAR data with the georeferenced data, either in ground geometry by orthorectifying the SAR information or in radar geometry by the inverse transformation, namely, radar-coding data from a geographic information system, to improve the analysis of SAR images and the result interpretation

Intra-sexual competition alters the relationship between testosterone and ornament expression in a wild territorial bird

Open Access funded by Natural Environment Research Council Under a Creative Commons licensePeer reviewedPublisher PD

Design and Implementation of Degenerate Microsatellite Primers for the Mammalian Clade

Microsatellites are popular genetic markers in molecular ecology, genetic mapping and forensics. Unfortunately, despite recent advances, the isolation of de novo polymorphic microsatellite loci often requires expensive and intensive groundwork. Primers developed for a focal species are commonly tested in a related, non-focal species of interest for the amplification of orthologous polymorphic loci; when successful, this approach significantly reduces cost and time of microsatellite development. However, transferability of polymorphic microsatellite loci decreases rapidly with increasing evolutionary distance, and this approach has shown its limits. Whole genome sequences represent an under-exploited resource to develop cross-species primers for microsatellites. Here we describe a three-step method that combines a novel in silico pipeline that we use to (1) identify conserved microsatellite loci from a multiple genome alignments, (2) design degenerate primer pairs, with (3) a simple PCR protocol used to implement these primers across species. Using this approach we developed a set of primers for the mammalian clade. We found 126,306 human microsatellites conserved in mammalian aligned sequences, and isolated 5,596 loci using criteria based on wide conservation. From a random subset of ∼1000 dinucleotide repeats, we designed degenerate primer pairs for 19 loci, of which five produced polymorphic fragments in up to 18 mammalian species, including the distinctly related marsupials and monotremes, groups that diverged from other mammals 120–160 million years ago. Using our method, many more cross-clade microsatellite loci can be harvested from the currently available genomic data, and this ability is set to improve exponentially as further genomes are sequenced

Conservation of Human Microsatellites across 450 Million Years of Evolution

The sequencing and comparison of vertebrate genomes have enabled the identification of widely conserved genomic elements. Chief among these are genes and cis-regulatory regions, which are often under selective constraints that promote their retention in related organisms. The conservation of elements that either lack function or whose functions are yet to be ascribed has been relatively little investigated. In particular, microsatellites, a class of highly polymorphic repetitive sequences considered by most to be neutrally evolving junk DNA that is too labile to be maintained in distant species, have not been comprehensively studied in a comparative genomic framework. Here, we used the UCSC alignment of the human genome against those of 11 mammalian and five nonmammalian vertebrates to identify and examine the extent of conservation of human microsatellites in vertebrate genomes. Out of 696,016 microsatellites found in human sequences, 85.39% were conserved in at least one other species, whereas 28.65% and 5.98% were found in at least one and three nonprimate species, respectively. An exponential decline of microsatellite conservation with increasing evolutionary time, a comparable distribution of conserved versus nonconserved microsatellites in the human genome, and a positive correlation between microsatellite conservation and overall sequence conservation, all suggest that most microsatellites are only maintained in genomes by chance, although exceptionally conserved human microsatellites were also found in distant mammals and other vertebrates. Our findings provide the first comprehensive survey of microsatellite conservation across deep evolutionary timescales, in this case 450 Myr of vertebrate evolution, and provide new tools for the identification of functional conserved microsatellites, the development of cross-species microsatellite markers and the study of microsatellite evolution above the species level

The genetic mating system of a sea spider with male-biased sexual size dimorphism: evidence for paternity skew despite random mating success

Male-biased size dimorphism is usually expected to evolve in taxa with intense male–male competition for mates, and it is hence associated with high variances in male mating success. Most species of pycnogonid sea spiders exhibit female-biased size dimorphism, and are notable among arthropods for having exclusive male parental care of embryos. Relatively little, however, is known about their natural history, breeding ecology, and mating systems. Here we first show that Ammothella biunguiculata, a small intertidal sea spider, exhibits male-biased size dimorphism. Moreover, we combine genetic parentage analysis with quantitative measures of sexual selection to show that male body size does not appear to be under directional selection. Simulations of random mating revealed that mate acquisition in this species is largely driven by chance factors, although actual paternity success is likely non-randomly distributed. Finally, the opportunity for sexual selection (Is), an indirect metric for the potential strength of sexual selection, in A. biunguiculata males was less than half of that estimated in a sea spider with female-biased size dimorphism, suggesting the direction of size dimorphism may not be a reliable predictor of the intensity of sexual selection in this group. We highlight the suitability of pycnogonids as model systems for addressing questions relating parental investment and sexual selection, as well as the current lack of basic information on their natural history and breeding ecology

Landscape homogenization due to agricultural intensification disrupts the relationship between reproductive success and main prey abundance in an avian predator

Selecting high-quality habitat and the optimal time to reproduce can increase individual fitness and is a strong evolutionary factor shaping animal populations. However, few studies have investigated the interplay between land cover heterogeneity, limitation in food resources, individual quality and spatial variation in fitness parameters. Here, we explore how individuals of different quality respond to possible mismatches between a cue for prey availability (land cover heterogeneity) and the actual fluctuating prey abundance.Peer reviewe

Expressions et micro-expressions spontanées de la face et de la voix en Interaction Homme-Machine : esquisse d'un modèle du "Feeling of Thinking".

Communicative interaction technologies focus more and more on human aspects. The informative position of expressions that are massively present out of the talk turns, through visible and audible micro-events, place the listener/interlocutor in a continuous communication of "Feeling of Thinking" (physiological, mental, emotional, intentional and attitudinal states). This work has been carried out on an emotionally induced corpus that greatly limits speech of the human-computer interaction. An empirical methodology based on ethological principles has been built to annotate audible and visible micro-gestures by 6 subjects. A perceptive analysis has measured the communicative relevance of certain gestural icons. A study of micro-gesture occurrences in the temporal organization of the task and within the turn-taking provides a cue of subjects' behavior. Finally, this study proposes an impressionistic characterization of the numerous vocal non-lexical sounds disseminated within the performances (mouth noises, grunts, fillers, interjections).Les technologies de l'interaction personne-machine se centrent de plus en plus sur l'humain. Le statut informatif des expressions présentes massivement en dehors des tours de parole, dans les micro-événements visibles ou audibles, inscrit le sujet dans une communication permanente du Feeling of Thinking (états physiologiques, mentaux, émotionnels, intentionnels et attitudinaux). Ce travail a été mené sur un corpus induit émotionnellement et restreignant l'interaction personne-machine au minima langagier. Une méthodologie empirique, sur des principes éthologiques, a d'abord été construite pour annoter les micro-gestes audibles et visibles de 6 sujets. Une analyse perceptive a ensuite mesuré la pertinence communicative de certaines icônes gestuelles. Puis a été menée une étude des occurrences des micro-gestes dans l'organisation temporelle de la tâche et des tours de parole, traçant ainsi le comportement des sujets. Enfin a été proposée une qualification impressionniste des nombreux sons vocaux non lexicaux qui ponctuent les performances (bruits de bouche, grunts, bursts, fillers, interjections)

Tactiques de reproduction et sélection sexuelle chez les ongulés<br /> Le cas d'une espèce territoriale avec faible dimorphisme sexuel de taille:<br /> le chevreuil européen (Capreolus Capreolus)

Co-tutelle entre:Laboratoire Comportement et Ecologie de la Faune Sauvage CEFS ­ INRA UPR35Chemin de Borde-Rouge-Auzeville BP 52627 F-31326 Castanet-Tolosan cedexet Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Sciences SLU, S-730 91, Riddarhyttan, SwedenThe aim of this study was to use for the first time molecular techniques (microsatellite genotyping and paternity analyses), in combination with field ecology studies, to provide data on male breeding success and identify the main determinants of variation in male breeding success in two long-term monitored populations of European roe deer Capreolus capreolus (Bogesund in Sweden and Trois Fontaines in France). The results show that males can sire up to 6 fawns per year and 14 fawns during their entire lifetime. As expected from the low level of sexual size dimorphism and the territorial mating system of roe deer, variance in male lifetime breeding success, and so opportunity for sexual selection, are lower than in highly dimorphic species such as red deer Cervus elaphus, suggesting a low polygyny level in roe deer. Males can successfully breed as young as 2 years of age, but breeding success of subadults is lower than that of older males. Successful breeding among sub-adults may be restricted to those high quality males that are able to defend a territory. Breeding success also tends to decline after 8 years of age (senescence), probably in relation to the loss of dominance. Male body mass and antler size positively affect male breeding success. It is known that antlers are used by males as a weapon in combats to defend their territory. However, my results also show that antler size is a honest signal of male phenotypic quality and may be used as a cue for rival males and females to assess male fighting ability, sexual vigor and/or phenotypic quality. In addition, male access to females and male breeding success are positively related to territory size, but not to habitat quality within a male's territory. Hence, the territorial mating system of roe deer differs from the conventional resource defense polygyny system and seems rather to conform to a "low risk ­ low gain" strategy. Finally, using paternity analyses, I also provide evidence that multiple paternity is likely, but infrequent, in roe deer, suggesting that multiple mating among females may have evolved as a means to enhance fertilisation success. This study provides new insights into the evolution of mating systems and sexual selection in ungulates.Le but de cette étude était d'utiliser les techniques moléculaires dans deux populations de chevreuil, pour estimer la variance du succès reproducteur des mâles et identifier les principaux déterminants de cette variance. Comme attendu du fait de son faible dimorphisme sexuel, la variance dans le succès reproducteur à vie des mâles, et donc l'opportunité pour la sélection sexuelle, sont faibles chez le chevreuil, suggérant un faible degré de polygynie. Les mâles peuvent se reproduire dès 2 ans, mais avec un succès reproducteur inférieur à celui des mâles plus âgés. Le succès reproducteur tend aussi à décroître après 8 ans. La masse corporelle, la taille des bois, et la taille du territoire des mâles, affectent positivement leur succès reproducteur, mais pas la qualité de l'habitat dans leur territoire. Cette étude apporte de nouveaux éléments sur l'évolution de la territorialité et la sélection sexuelle chez les ongulés sauvages