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A central tenet of ecology and biogeography is that the broad outlines of species ranges are determined by climate, whereas the effects of biotic interactions are manifested at local scales. While the first proposition is supported by ample evidence, the second is still a matter of controversy. To address this question, we develop a mathematical model that predicts the spatial overlap, i.e. co-occurrence, between pairs of species subject to all possible types of interactions. We then identify the scale of resolution in which predicted range overlaps are lost. We found that co-occurrence arising from positive interactions, such as mutualism (+/+) and commensalism (+/0), are manifested across scales. Negative interactions, such as competition (−/−) and amensalism (−/0), generate checkerboard patterns of co-occurrence that are discernible at finer resolutions but that are lost and increasing scales of resolution. Scale dependence in consumer–resource interactions (+/−) depends on the strength of positive dependencies between species. If the net positive effect is greater than the net negative effect, then interactions scale up similarly to positive interactions. Our results challenge the widely held view that climate alone is sufficient to characterize species distributions at broad scales, but also demonstrate that the spatial signature of competition is unlikely to be discernible beyond local and regional scales. Fil: Araujo, Miguel B.. Imperial College London; Reino Unido Fil: Rozenfeld, Alejandro Fabian. Imperial College London; Reino Unido. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

This paper considers the formation control of multiple underactuated surface vessel. A distributed cooperative control using the relative information among neighboring vehicles is proposed such that the flock of multiple vehicles forms a desired geometric formation pattern whose center moves along a desired trajectory. In order to guarantee safe flock navigation and interaction of vehicles with the environment, we propose to extend the designed formation tracking controller to more sophisticated algorithm that prevent the vehicles from colliding with environmental obstacles with unknown sizes and locations based on a Decentralized Constrained Optimizing Problem ”DCOP” strategy. Fil: Rozenfeld, Alejandro Fabian. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Departamento de Electromecánica. Grupo INTELYMEC; Argentina. Universidad de Las Islas Baleares. Departamento de Fisica; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; Argentina Fil: Ghommam, Jawhar. No especifíca; Fil: Picos, Rodrigo. Universidad de Las Islas Baleares. Departamento de Fisica; España Fil: Acosta, Gerardo Gabriel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Departamento de Electromecánica. Grupo INTELYMEC; Argentina. Universidad de Las Islas Baleares. Departamento de Fisica; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; Argentina