Sexual conflict. The evolution of infanticide by males in mammalian societies.

Male mammals often kill conspecific offspring. The benefits of such infanticide to males, and its costs to females, probably vary across mammalian social and mating systems. We used comparative analyses to show that infanticide primarily evolves in social mammals in which reproduction is monopolized by a minority of males. It has not promoted social counterstrategies such as female gregariousness, pair living, or changes in group size and sex ratio, but is successfully prevented by female sexual promiscuity, a paternity dilution strategy. These findings indicate that infanticide is a consequence, rather than a cause, of contrasts in mammalian social systems affecting the intensity of sexual conflict.This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version will be published in Science (http://www.sciencemag.org/magazine)

Social network inheritance and differentiation in wild baboons

Immatures' social development may be fundamental to understand important biological processes, such as social information transmission through groups, that can vary with age and sex. Our aim was to determine how social networks change with age and differ between sexes in wild immature baboons, group-living primates that readily learn socially. Our results show that immature baboons inherited their mothers' networks and differentiated from them as they aged, increasing their association with partners of similar age and the same sex. Males were less bonded to their matriline and became more peripheral with age compared to females. Our results may pave the way to further studies testing a new hypothetical framework: in female-philopatric societies, social information transmission may be constrained at the matrilineal level by age- and sex-driven social clustering

The submissive pattern of postconflict affiliation in asymmetric relationships: a test in male and sexually coerced female baboons

Reconciliation, or postconflict (PC) affiliation between former opponents, is a widespread conflict management strategy in animal societies, so-named for its relationship repair function. However, another possibility is that PC affiliation reflects a submissive response of victims towards aggressors to limit conflict escalation when the power imbalance between the opponents is large. Here we investigated this hypothesis in a highly asymmetric relationship context: heterosexual wild chacma baboon, Papio ursinus, dyads involving sexually receptive females, where sexual coercion by males is common. We found several lines of support for the submissive hypothesis in the context of sexual coercion. First, rates of sexual and nonsexual PC affiliative interactions in these dyads exhibited significant and comparable increases compared to baseline conditions (ca. three-fold). Second, the baseline strength of the heterosexual social bond (outside of an aggressive context) did not predict the likelihood of sexual and nonsexual PC affiliation. Third, mate-guarded females, who could not escape the proximity of their aggressor (and faced high risks of renewed aggression), exhibited the most PC affiliation with males. Finally, most PC affiliation sequences contained at least one sexual act, and the first sexual affiliative act was primarily initiated by females via presenting. This suggests that female victims affiliate in a submissive way by displaying sexual compliance to aggressive males. Nevertheless, we cannot exclude the co-occurrence of ‘true’ reconciliation: a quarter of PC affiliations between males and receptive females were exclusively nonsexual, and the first general affiliative act was equally initiated by males and females. Overall, our results suggest a mixed PC affiliation strategy in which submission may play an important role in highly asymmetric relationships and indicate that the function of PC affiliation may vary from submission to reconciliation depending on the species, dyads, individuals and conflicts under consideration. Future research on PC interactions would usefully consider this full spectrum

Connaissances actuelles sur les méthodes de lutte contre les helminthoses digestives du cheval

Cette étude bibliographique vise à faire le point sur les différentes méthodes de lutte actuelles contre les helminthoses digestives des chevaux. Après un bref rappel phylogénique et biologique sur les strongles des équidés, les protocoles de prévention couramment utilisés sont passés en revue. La chimioprophylaxie, pratique largement majoritaire aujourd'hui, est envisagée de manière approfondie, avec une description des molécules disponibles et des précisions quant à leur mode d'action et leurs spectres respectifs. Le phénomène de la résistance des strongles aux anthelminthiques est abordé ensuite : définition, méthodes diagnostiques et épidémiologie descriptive (espèces parasitaires concernées, classes thérapeutiques impliquées et distribution géographique) sont présentées. On prête une attention particulière aux aspects épidémiologiques analytiques, à savoir le déterminisme génétique et environnemental de l'apparition et du développement de la résistance. Les effets de chacun des facteurs biologiques connus, respectivement liés aux parasites, aux antiparasitaires et à la conduite d'élevage sont ainsi discutés en détail. Une dernière partie est consacrée à la gestion de ce problème, et détaille les stratégies permettant de retarder son émergence et d'enrayer son extension. Enfin, les perspectives présentes et à venir en matière de lutte antiparasitaire chez les chevaux sont évoquées

A Catalog of Patterns for Concept Lattice Interpretation in Software Reengineering

International audienceFormal Concept Analysis (FCA) provides an important approach in software reengineering for software understanding, design anomalies detection and correction. However, FCA-based approaches have two problems: (i) they produce lattices that must be interpreted by the user according to his/her understanding of the technique and different elements of the graph; and, (ii) the lattice can rapidly become so big that one is overwhelmed by the mass of information and possibilities. In this paper, we present a catalogue of important patterns in concept lattices, which can allow automating the task of lattice interpretation. The approach helps the reengineer to concentrate on the task of reengineering rather than understanding a complex lattice. We provide interpretation of these patterns in a generalized manner and illustrate them on various contexts constructed from program information of different open-source systems. We also present a tool that allows automated extraction of the patterns from concept lattices

Performances of Galois Sub-hierarchy-building Algorithms

LNAI est une "Sublibrary de LNCS"International audienceThe Galois Sub-hierarchy (GSH) is a polynomial-size repre- sentation of a concept lattice which has been applied to several fields, such as software engineering and linguistics. In this paper, we analyze the performances, in terms of computation time, of three GSH-building algorithms with very different algorithmic strategies: Ares, Ceres and Pluton. We use Java and C++ as imple- mentation languages and Galicia as our development platform. Our results show that implementations in C++ are significantly faster, and that in most cases Pluton is the best algorithm

Relational Data Exploration by Relational Concept Analysis

Relational Concept Analysis [4] is an extension to FCA con- sidering several contexts with relations between them. Often used to extend the knowledge that can be learned with FCA, RCA also meets the issue of combinatorial explosion. The initial specification of RCA implies a monotonic growth of the number of concepts and an exhaustiveness of all the concepts that can be obtained when a fixed point is reached. In this position paper we propose a different specification of RCA that permits an interactive exploration of the data by letting the choice of the user for each step. This change will permit to handle richer relational data in a more flexible way by restraining the relations explored at each step hence reducing the number of created concepts

Learning Model Transformations from Examples using FCA: One for All or All for One?

International audienceIn Model-Driven Engineering (MDE), model transformations are basic and primordial entities. An efficient way to assist the definition of these transformations consists in completely or partially learning them. MTBE (Model Transformation By-Example) is an approach that aims at learning a model transformation from a set of examples, i.e. pairs of transformation source and target models. To implement this approach, we use Formal Concept Analysis as a learning mechanism in order to extract executable rules. In this paper, we investigate two learning strategies. In the first strategy, transformation rules are learned independently from each example. Then we gather these rules into a single set of rules. In the second strategy, we learn the set of rules from all the examples. The comparison of the two strategies on the well-known transformation problem of class diagrams to relational schema showed that the rules obtained from the two strategies are interesting. Besides the first one produces rules which are more proper to their examples and apply well compared to the second one which builds more detailed rules but larger and more difficult to analyze and to apply

Contribution A L’étude D’élaboration D’acier A Carbone A Madagascar

A l’origine de sa création, c’est la recherche appliquée pour le développement qui justifie l’existence d’un organisme de recherche publique. La présente étude est une tentative de contribution à la production d’acier à Madagascar. Elle se propose une méthode qui permet de convertir les déchets métalliques en acier. Le but du travail est de valoriser les produits réfractaires siliceux du CNRIT pour le garnissage d’un petit convertisseur. Le mode d’injection par le coté latéral du convertisseur à l’aide d’une tuyère à multiple trous a permis de faire circuler un grand débit d’oxygène et d’améliorer l’oxydation des impuretés dans la fonte. Par rapport au mode de soufflage par le haut, l’injection par le coté latéral réduit la teneur en azote dans le métal. En outre, une circulation uniforme de l’oxygène sur le liquide favorise la coalescence et la remontée donc l’assimilation des particules non métalliques dans le métal par la scorie. Mais la faible capacité du four entraîne un fort accroissement de sa surface spécifique. Il y a donc une grande perte de chaleur par unité de métal.

The eco-evolutionary landscape of power relationships between males and females

In animal societies, control over resources and reproduction is often biased towards one sex. Yet, the ecological and evolutionary underpinnings of male-female power asymmetries remain poorly understood. We outline a comprehensive framework to quantify and predict the dynamics of male-female power relationships within and across mammalian species. We show that male-female power relationships are more nuanced and flexible than previously acknowledged. We then propose that enhanced reproductive control over when and with whom to mate predicts social empowerment across ecological and evolutionary contexts. The framework explains distinct pathways to sex-biased power: coercion and male-biased dimorphism constitute a co-evolutionary highway to male power, whereas female power emerges through multiple physiological, morphological, behavioural, and socioecological pathways