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El objetivo de este proyecto era evaluar el interés de los estudiantes de Biología por un grado bilingüe. Mediante cuestionarios, seminarios informativos y clases en inglés se identificaron las variables que afectan a la demanda y la perspectiva de éxito. Demostramos que los estudiantes del Grado en Biología tienen buen nivel de inglés y están muy interesados en una docencia en inglés. Desearían cursos o clases en inglés a partir del primer curso. El interés se basa sobre todo en el deseo de poder trabajar y estudiar en el extranjero. Actividades en inglés y seminarios informativos incrementarían el interés y la demanda de docencia en inglés.

In March 1988, the three-colour-code currently used to mark Common Cranes (Grus grus) was employed for the first time in Spain. This banding system had been proposed by Spanish researchers at the First Meeting of the European Crane Working Group in 1985 in Hungary, as an alternative to the harder-to-read alphanumeric rings. Between 1988 and 1992, the first 109 cranes were colour-banded with this new system at Gallocanta lake. During the Palearctic Crane Workshop, Estonia 1989, this banding system was definitely accepted by the European Crane Working Group. In 1995, the German Working Group invited the Spanish team to introduce the new system, as well as radio-tagging techniques, during a chick-marking campaign in Germany, and since then, similar campaigns to establish the new three-colour codes were carried out in several European and Asian countries. Hundreds of resightings of marked cranes soon accumulated in a database first coordinated by the Spanish Working Group, who also provided the colour rings. In January 2009, the website iCORA was opened by the German Working Group, and today ca. 140000 resightings of more than 3800 marked cranes are stored in that database. However, not all observers send their data to iCORA, and much information is stored in national ringing centres, or in the well-established EURING databank. During the last three decades, researchers and volunteers from all over Europe have been involved in crane banding and resighting activities, and today the data accumulated on life history parameters and use of migratory routes could hugely increase our knowledge of the species' biology. However, little information has been published as scholarly articles, and media outreach of crane banding results is also clearly insufficient. Here we propose a joint effort of all researchers who have historically taken significant roles in crane banding and resighting, together with personnel responsible for database management, to carry out a first thorough

Sex allocation models still fail to predict the complex sex ratio patterns in broods of vertebrates. A major problem when studying motherebrood interactions is the difficulty in disentangling hypotheses involving maternal preferences from processes that do not imply maternal manipulation. We studied maternal resource allocation in mixed-sex, same-sex and single-chick broods in the great bustard, Otis tarda. Females normally rear a single chick, and previous work has shown that maternal investment influences male more than female breeding success. Therefore, mothers of two-chick broods were assumed to be in good condition and candidates to show a preference for sons. Results showed that male chicks of mixed-sex broods remained close to the mother for twice as long as their sisters, and received double the number of maternal feedings. However, sex differences in maternal feeding rate disappeared when considering only simultaneous begging approaches from both siblings. Proximity to the mother and its interaction with begging approach intensity were the factors determining the higher begging success of male chicks. In single-chick broods, females did not receive fewer maternal feedings than males. Overall, our results suggest that female chicks of mixed-sex broods become outcompeted by their larger brothers, which remain close to the mother much longer, preventing their sisters from taking a larger share of maternal feedings. We conclude that mothers do not show a preference for feeding male over female chicks, and that the sex differences in feeding rate are determined by the higher food requirements of male chicks due to their sexually selected, much faster growth rates. The higher mortality of females in mixed-sex broods contrasts with the pattern of male-biased mortality typical in this species, and supports our interpretation of an asymmetric competitive ability of male offspring as the mechanism responsible for the sex bias in maternal expenditure., Ministerio de Economía y Competitividad (MINECO), Instituto Nacional para la Conservación de la Naturaleza, Junta de Castilla y León, Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

Eurasian Cranes (Grus grus) started staging at Gallocanta, NE Spain, in 1973, just after waterfowl hunting was prohibited in the lake. Since then, crane numbers increased in the area each year, due to the abundant food resources provided by intensive cereal farming. During the mid-1980s, farmers started claiming compensations for the damages caused by cranes in their fields. A study revealed that the overall damage was negligible but found that in a few fields close to roosting or drinking sites cranes consumed up to 30% of the planted cereal grain. The regional authorities were not able to manage the social alarm appropriately, and farmers started chasing the cranes from fields and roosting sites. These disturbances contributed to a reverse in the increasing crane population trend of the previous decade, and many cranes shifted northwards to winter at new staging areas in France, where they found abundant food in maize (corn [Zea mays]) stubble. Today, a delicate equilibrium has been reached with the provision of compensations through agri-environmental measures within a Rural Development Program funded by the European Union. However, the amount of compensations still continues under strong debate, and the conflict is far from being solved. Compensatory payments do not represent a sustainable solution to the problem because they lead to further social conflicts. To definitely solve them, additional management measures should be evaluated and implemented.

[EN] Many bird populations have recently changed their migratory behavior in response to alterations of the environment. We collected data over 16 years on male Great Bustards (Otis tarda), a species showing a partial migratory pattern (sedentary and migratory birds coexisting in the same breeding groups). We conducted population counts and radio tracked 180 individuals to examine differences in survival rates between migratory and sedentary individuals and evaluate possible effects of these differences on the migratory pattern of the population. Overall, 65% of individuals migrated and 35% did not. The average distance between breeding and postbreeding areas of migrant individuals was 89.9 km, and the longest average movement of sedentary males was 3.8 km. Breeding group and migration distance had no effect on survival. However, mortality of migrants was 2.4 to 3.5 times higher than mortality of sedentary birds. For marked males, collision with power lines was the main cause of death from unnatural causes (37.6% of all deaths), and migratory birds died in collisions with power lines more frequently than sedentary birds (21.3% vs 6.3%). The percentage of sedentary individuals increased from 17% in 1997 to 45% in 2012. These results were consistent with data collected from radio-tracked individuals: The proportion of migratory individuals decreased from 86% in 1997–1999 to 44% in 2006–2010. The observed decrease in the migratory tendency was not related to climatic changes (temperatures did not change over the study period) or improvements in habitat quality (dry cereal farmland area decreased in the main study area). Our findings suggest that human-induced mortality during migration may be an important factor shaping the migration patterns of species inhabiting humanized landscapes., [ES] El comportamiento migratorio de muchas poblaciones de aves ha cambiado recientemente como consecuencia de las alteraciones ambientales. Durante 16 años estudiamos la conducta migratoria de machos de Avutarda Común Otis tarda, un ave con un patrón de migración parcial (individuos sedentarios y migradores coexisten en los mismos grupos). Realizamos censos de población y seguimos a 180 individuos marcados con emisores de radio para examinar las diferencias en las tasas de supervivencia entre los machos migradores y los sedentarios; y evaluar los posibles efectos de estas diferencias sobre el patrón migratorio de la población. Globalmente, el 65% de los individuos fueron migradores y el 35% sedentarios. La distancia media entre las áreas de reproducción y las post-reproductivas de los migradores fue de 89.9 km y la de los sedentarios de 3.8 km. Ni el grupo reproductor ni la distancia de migración tuvieron efectos sobre la supervivencia. Sin embargo, los individuos migradores tuvieron entre 2.4 y 3.5 veces mayor riesgo de mortalidad que los sedentarios. La colisión con líneas eléctricas fue la principal causa de mortalidad de los machos marcados (37.6% de todas las muertes), y los migradores murieron por colisión con líneas eléctricas con mayor frecuencia que los sedentarios (21.3% versus 6.3%). El porcentaje de individuos sedentarios aumentó desde el 17% en 1997 al 45% en 2012. Estos resultados fueron confirmados por los datos procedentes de individuos marcados: la proporción de migradores disminuyó desde el 86% en 1997–1999 al 44% en 2006–2010. La disminución de la tendencia migratoria no estuvo relacionada con cambios climáticos (las temperaturas no cambiaron durante el periodo de estudio) o con mejoras de la calidad del hábitat (la superficie de cultivos de cereal disminuyó en el área de estudio principal). Nuestros hallazgos sugieren que la mortalidad durante la migración provocada por las actividades humanas puede ser un factor muy importante en el desarrollo

La finalidad de este proyecto final de carrera es demostrar las nuevas capacidades de comunicación de los dispositivos móviles de última generación, el proyecto se basa en el iPhone. Este dispositivo abre las puertas al desarrollo de aplicaciones peer-to-peer.

We modelled great bustard abundance patterns and their spatial structure in relation to habitat and landscape variables. We developed Generalized Linear Models (GLM) using long term data series – years 1997–2006 – during the breeding season in Madrid region, central Spain. Our main goal was to assess spatial and temporal variability effects on habitat selection in this species evaluating the impact of interannual variability on habitat selection, the consistency of model predictions among years and the effect of data accumulation in the model performance. We examined the predictive ability of our models using internal and external validation techniques. We built separate models for each year and different models using the addition of several year data. The model perfomance increased as more census data were included in the calibration. One-off temporal data was insufficient to predict great bustard abundance properly. The final model (calibrated with all period data) showed a reasonable accuracy, attending to the validation tests. The variability in habitat suitability predictions between annual models does not seem to be caused by changes in habitat selection between years because the global model had a better explanatory ability than annual models. As far as interannual variability in spring greenness is concerned, the most variable sites are preferred, suggesting a selection for sites with smaller land use units and with a traditional rotation system. The great bustard abundance in Madrid was affected by the presence of other conspecifics but this pattern was conditioned to the existence of a suitable habitat denoted by the other variables in the final model. Future persistence of great bustards in Madrid region depends on a sustainable economic development that maintains traditional land uses, at least in areas with high ecological value for great bustards, whether they are occupied or not

In this paper, we present a detailed evaluation of a set of well-known Machine Learning classifiers in front of dynamic and non-deterministic software anomalies. The system state prediction is based on monitoring system metrics. This allows software proactive rejuvenation to be triggered automatically. Random Forest approach achieves validation errors less than 1% in comparison to the well-known ML algorithms under avaluation. In order to reduce automatically the number of monitored parameters, needed to predict software anomalies, we analyze Lasso Regularization technique jointly with the Machine Learning classifiers to evaluate how the prediction accuracy could be guaranteed within an acceptable threshold. This allows to reduce drastically (around 60% in the best case) the number of monitoring parameters. The framework, based on ML and Lasso regularization techniques, has been validated using an e-commerce environment with Apache Tomcat server, and MySql database server., Postprint (author’s final draft)

The availability of the Information Technologies for everything, from everywhere, at all times is a growing requirement. We use information Technologies from common and social tasks to critical tasks like managing nuclear power plants or even the International Space Station (ISS). However, the availability of IT infrastructures is still a huge challenge nowadays. In a quick look around news, we can find reports of corporate outage, affecting millions of users and impacting on the revenue and image of the companies. It is well known that, currently, computer system outages are more often due to software faults, than hardware faults. Several studies have reported that one of the causes of unplanned software outages is the software aging phenomenon. This term refers to the accumulation of errors, usually causing resource contention, during long running application executions, like web applications, which normally cause applications/systems to hang or crash. Gradual performance degradation could also accompany software aging phenomena. The software aging phenomena are often related to memory bloating/ leaks, unterminated threads, data corruption, unreleased file-locks or overruns. We can find several examples of software aging in the industry. The work presented in this thesis aims to offer a proactive and predictive software rejuvenation solution for Internet Services against software aging caused by resource exhaustion. To this end, we first present a threshold based proactive rejuvenation to avoid the consequences of software aging. This first approach has some limitations, but the most important of them it is the need to know a priori the resource or resources involved in the crash and the critical condition values. Moreover, we need some expertise to fix the threshold value to trigger the rejuvenation action. Due to these limitations, we have evaluated the use of Machine Learning to overcome the weaknesses of our first approach to obtain a proactive and predictive, Postprint (published version)

Factors responsible for individual variation in partial migration patterns are poorly known, and identifying possible causes of these changes is essential for understanding the flexibility in migratory behavior. Analyzing 190 life histories of great bustards Otis tarda radio-tagged in central Spain, we investigated the changes in migratory tendency across lifetime in this long-lived bird, and how migratory flexibility is related to individual condition. In females migratory behavior was not fixed individually. For every age class there was a fraction of ca 15–30% of females that changed their migratory pattern between consecutive years. Migrant females tended to remain sedentary in years when they had dependent young to attend. These findings show that the female migratory tendency is a behaviorally flexible, condition-dependent trait. Immature females usually acquired their migratory behavior by learning from the mother in their first winter or by social transmission from other migratory females in their second winter. As for immature males, their summer migratory behavior was not related to mother–offspring transmission, but learned from adult males. We found that their age-related increase in migratory tendency was associated to a greater integration in flocks of migrant adult males. These results show that within the partial migration system, cultural transmission mechanisms, either mediated by kin or not, and individual condition, may contribute to shape the migratory tendency. Our study reinforces the view that the migratory behavior is an evolutionary complex trait conditioned by the interaction of individual, social and environmental factors. Particularly in long-lived species with extended parental care, the inherited migration program may be shaped by mother–offspring and social transmission of migratory patterns

[EN] We investigated the spatial arrangement of Great Bustard Otis tarda nests relative to leks in 55 females captured at four lek sites and radio-tracked through 1–6 years in a protected area in central Spain. Although females showed a tendency to nest close to the lek centers where they were observed during the mating season (29% did it at <2 km), lek-to-nest distances ranged between 0.22 and 53.82 km. This resulted in most nest-sites (64%) being outside the lek areas where the female had mated, often closer to nearby leks, and sometimes far from any lek, in areas used only for nesting, outside the protected area (25%). The distribution of nest-to-nearest-lek distances did not differ from that of randomly distributed control sites, indicating that nest-sites were not aggregated, but dispersed over the whole suitable habitat within a large area around leks. Females with and without hatching success did not differ in their mean lek-to-nest distance. These results suggest that females used the whole suitable habitat available for nesting, and did not base nest-site selection on factors related to density-dependent disturbances or predation risks at leks (lek avoidance hypothesis). In this and other lekking birds, managers have often restricted conservation efforts to lek areas, under the wrong assumption that these would include most nest-sites. If a much larger region including most nesting habitat is not protected, Great Bustards in our study population might eventually be forced to nest at higher densities within the protected area, with a consequent density-dependent reduction in the mean breeding success of the population, [DE] Für 55 Großtrappen-Weibchen, die an 4 Balzplätzen gefangen und mittels kleiner Sender über 1–6 Jahre in einem Naturschutzgebiet in Zentralspanien verfolgt wurden, untersuchten wir die räumliche Verteilung der Nester in Beziehung zu den Balzplätzen. Zwar zeigten die Weibchen eine Tendenz, nahe desjenigen Balzplatzes zu nisten, an dem sie während der Balzzeit beobachtet worden waren (weniger als 2 km entfernt bei 29% der Tiere), aber die Entfernungen der Nester von den Balzplätzen reichten von 0,22 bis 53,82 km. 64% aller Nistplätze lagen außerhalb der Balzplatz-Areale, in denen die Weibchen begattet worden waren, manchmal näher zu anderen Balzplätzen und gelegentlich (in 25% der Fälle) weit entfernt von irgendwelchen Balzplätzen, außerhalb des Naturschutzgebietes, und nur zum Nisten ausgewählt. Die Verteilung der Entfernungen „Nest zum nächstgelegenen Balzplatz“ unterschied sich nicht signifikant von derjenigen der zufällig ausgesuchten Kontroll-Areale, was den Schluss nahe legt, dass die Nester nicht irgendwo gehäuft auftraten, sondern sich über das gesamte geeignete Habitat innerhalb eines weiten Gebietes um die Balzplätze herum verteilten. Auch zwischen Weibchen mit und ohne Bruterfolg konnte kein Unterschied in den Entfernungen ihrer Nester von den Balzplätzen festgestellt werden. Diese Ergebnisse lassen vermuten, dass die Weibchen bei der Wahl des Nistplatzes das gesamte, zum Nisten geeignete Habitat nutzten, ohne Berücksichtigung von Faktoren wie Nistplatzdichte oder spezielles Beute-Risiko (Balzplatz-Vermeidungs-Hypothese). Bei dieser und anderen Arten mit vergleichbarem Balzverhalten wurden Schutzmaßnahmen oft auf die Balzplätze begrenzt, in der irrigen Annahme, diese enthielten die meisten Nistplätze. Aber wenn nicht ein größeres Gebiet, inklusive der meisten Nistplätze, geschützt wird, könnten die Großtrappen der von uns untersuchten Population einmal gezwungen sein, innerhalb des geschützten Gebiets in größerer Dichte zu nisten, mit dem im Mittel durc

Unplanned system outages have a negative impact on company revenues and image. While the last decades have seen a lot of efforts from industry and academia to avoid them, they still happen and their impact is increasing. According to many studies, one of the most important causes of these outages is software aging. Software aging phenomena refers to the accumulation of errors, usually provoking resource contention, during long running application executions, like web applications, which normally cause applications/systems hang or crash. Determining the software aging root cause failure, not the resource or resources involved in, is a huge task due to the growing day by day complexity of the systems. In this paper we present a monitoring framework based on Aspect Programming to monitor the resources used by every application component in runtime. Knowing the resources used by every component of the application we can determine which components are related to the software aging. Furthermore, we present a case study where we evaluate our approach to determine in a web application scenario, which components are involved in the software aging with promising results., Postprint (published version)

El objetivo del presente proyecto es crear un juego educacional basándose en el ComeLetras desarrollado por Raquel M. Crespo1 para un dispositivo móvil, en este caso, el iPhone. Debido al auge de los dispositivos móviles, hemos considerado oportuno desarrollar ese mismo juego para una de estas plataformas, ya que de esta forma puede llegar a más usuarios y, sin lugar a dudas, jugar en cualquier lugar, en cualquier momento. Este proyecto está enfocado en desarrollar el juego para el dispositivo móvil de Apple iPhone. Entre las razones para elegir esta plataforma y no otra, están la innovación que representa iPhone en el mercado, gracias en parte a los controles táctiles y los acelerómetros, la documentación extensa y el SDK ofrecidos por Apple, y la compatibilidad inter-dispositivos de dicha marca, por ejemplo iPod Touch. Por lo tanto, este proyecto tiene doble objetivo. Uno, el objetivo educacional del juego, ya que está pensado para mejorar el vocabulario. Y el segundo y no menos importante, el objetivo del PFC, que es desarrollar un juego en una plataforma novedosa, con un lenguaje de programación nuevo, un SDK y un sistema operativo (iPhone OS) nuevo nunca dados en la carrera. Seguidamente, pasaremos a introducir más profundamente todos los objetivos del juego, detalles, mecánicas y otros conceptos que nos servirán para entender el resto de documento.

The growing complexity of software systems is resulting in an increasing number of software faults. According to the literature, software faults are becoming one of the main sources of unplanned system outages, and have an important impact on company benefits and image. For this reason, a lot of techniques (such as clustering, fail-over techniques, or server redundancy) have been proposed to avoid software failures, and yet they still happen. Many software failures are those due to the software aging phenomena. In this work, we present a detailed evaluation of our chosen machine learning prediction algorithm (M5P) in front of dynamic and non-deterministic software aging. We have tested our prediction model on a three-tier web 12EE application achieving acceptable prediction accuracy against complex scenarios with small training data sets. Furthermore, we have found an interesting approach to help to determine the root cause failure: The model generated by machine learning algorithms., Postprint (published version)

For a non IT expert to use services in the Cloud is more natural to negotiate the QoS with the provider in terms of service-level metrics –e.g. job deadlines– instead of resourcelevel metrics –e.g. CPU MHz. However, current infrastructures only support resource-level metrics –e.g. CPU share and memory allocation– and there is not a well-known mechanism to translate from service-level metrics to resource-level metrics. Moreover, the lack of precise information regarding the requirements of the services leads to an inefficient resource allocation –usually, providers allocate whole resources to prevent SLA violations. According to this, we propose a novel mechanism to overcome this translation problem using an online prediction system which includes a fast analytical predictor and an adaptive machine learning based predictor. We also show how a deadline scheduler could use these predictions to help providers to make the most of their resources. Our evaluation shows: i) that fast algorithms are able to make predictions with an 11% and 17% of relative error for the CPU and memory respectively; ii) the potential of using accurate predictions in the scheduling compared to simple yet well-known schedulers., Preprint

Traditionally, performance has been the most important metrics when evaluating a system. However, in the last decades industry and academia have been paying increasing attention to another metric to evaluate servers: availability. A web server may serve many users when running, but if it is out of service too much time, it becomes useless and expensive. The industry has adopted several techniques to improve system availability, yet crashes still happen. In this paper, we propose a new framework to predict time-to-failure when the system is suffering transient failures that consume resources randomly. We study which machine learning algorithms build a more accurate model of the behavior of the anomaly system, and focus on Linear Regression and Decision Tree algorithms. Our preliminary results show that M5P (a Decision Tree algorithm) is the best option to model the behavior of the system under the random injection of memory leaks., Postprint (published version)

La enseñanza de contenidos técnicos en grupos multidisciplinares es una tarea compleja debido a la diversidad de los conocimientos iniciales de los alumnos implicados. Sin embargo esta dificultad puede llegar a convertirse en una poderosa herramienta. En este artículo se presenta la experiencia obtenida durante una asignatura de software libre impartida a un grupo multidisciplinar formado por alumnos de distintas carreras técnicas. La base de nuestra propuesta es obligar a los estudiantes a cooperar forzando grupos compuestos por alumnos de diferentes carreras. Este tipo de agrupación obliga a los alumnos a realizar trabajo cooperativo y aprendizaje entre iguales, lo que les permite desarrollar habilidades tanto técnicas como profesionales. Nuestros resultados muestran que con este enfoque se consiguen buenos resultados tanto en el aprendizaje como en la aceptación por parte de los alumnos de la asignatura y del método de enseñanza., Peer Reviewed

One of the primary tools for performance analysis of multi-tier systems are standardized benchmarks. They are used to evaluate system behavior under different circumstances to assess whether a system can handle real workloads in a production environment. Such benchmarks are also helpful to resolve situations when a system has an unacceptable performance or even crashes. System administrators and developers use these tools for reproducing and analyzing circumstances which provoke the errors or performance degradation. However, standardized benchmarks are usually constrained to simulating a set of pre-fixed workload distributions. We present a benchmarking framework which overcomes this limitation by generating real workloads from pre-recorded system traces. This distributed tool allows more realistic testing scenarios, and thus exposes the behavior and limits of a tested system with more details. Further advantage of our framework is its flexibility. For example, it can be used to extend standardized benchmarks like TPC-W thus allowing them to incorporate workload distributions derived from real workloads., Peer Reviewed, Postprint (published version)

Cloud users want to express their requirements in terms of high-level metrics (e.g. in terms of execution time, not in terms of CPU MHz). Moreover, at the submission time they would like to know if the resource provider will ful l with their requirements in order to decide if they would rather prefer another provider. On the other hand, the resource provider have to translate these high-level metrics into hard- ware related metrics, to know if he have enough resources to execute the user's requests. In this context, we present our prediction system to foresee the amount of CPU required for a job to nish before its deadline. This prediction system uses machine learning techniques to learn about the jobs and on-line adjust itself. Before all this training is done, the Prediction System uses an analytical model for this purpose. We also contribute with a deadline-based scheduler which uses these predictions to discard jobs that will not meet its deadline in order to maximize the provider's revenue by means of a dynamic and effi cient resource allocation to jobs. We show how our system is able to provide higher revenue to resource providers compared to simple yet well known schedulers like EDF, SJF, etc., Peer Reviewed, Postprint (published version)

We explored migration patterns in Great bustards (Otis tarda), a species that shows strong sexual selection and the most extreme sexual size dimorphism among birds. The aim was to explain differential migration, examining whether Great bustards fulfil the main predictions of bird migration theory hypotheses and sexual segregation theory hypotheses. We radio-tracked the seasonal movements of 65 males and 68 females in central Spain. We found four main sexual differences. First, the proportion of migratory males was higher than that of migratory females (86% vs. 51%). Second, males abandoned the leks immediately after the mating season (late May to early Jun.), whereas females remained there for another 3–7 mo. Third, 54% of the migratory males used two different post-breeding areas, the first located northwards at 82 km from the breeding sites in summer, and the second southwards at 50 km in autumn–winter. Migratory females used only one area in autumn–winter which coincided geographically with that of males. And fourth, males returned to the breeding areas earlier (between Sep. and Mar.) than females (between Jan. and Apr.). These results show that the Great bustard is a differential migrant by sex in central Spain and support the weather sensitivity hypothesis (males were less tolerant to summer heat) and the specialization hypothesis (exclusive maternal care of the brood by females). Sexual differences in migratory behaviour are probably ultimately determined by the strong sexual selection in this species

[EN] The Great Bustard (Otis tarda) is one of the heaviest flying birds and the most sexually dimorphic living bird. Adult males weighed 2.48× more than females, and their linear measurements were 18–30% larger. Weight increased between the prebreeding and breeding seasons by 16% in females and 20% in males. Sexual size dimorphism emerges very early in development and explains why growth in males is so costly. Weight and central toe length were hyperallometric when related to wing length in males but isometric in females and varied more in males, as compared with females and with other male traits. Although hyperallometry and high variability have frequently been used to invoke sexual selection as a driving force, our results support different functional hypotheses for the evolution of each trait. Male–male competition is intense in this lekking species, and high rank among males and access to females are weight-dependent. Thus, sexual selection has likely pushed male weight close to the limit imposed by powered flight. Because Great Bustards are mostly cursorial, the hyperallometry of the central toes of males in relation to wing length most likely evolved for support and balance., [ES] Otis tarda es el ave con mayor dimorfismo sexual y una de las de mayor peso entre las que conservan la capacidad de vuelo. Los machos adultos capturados en España fueron 2.48 veces más pesados que las hembras y sus medidas lineales un 18–30% mayores que las de las hembras. Entre finales del invierno y la estación reproductiva el peso medio aumentó en un 16% en las hembras y en un 20% en los machos. El dimorfismo sexual se manifiesta en los pollos de esta especie a edades muy tempranas, lo que implica que los machos han de sufrir un mayor costo durante el crecimiento que las hembras. El peso y el dedo medio mostraron en los machos un desarrollo hiperalométrico en relación con la longitud alar, mientras que estas medidas fueron isométricas en las hembras. Además, dichas medidas fueron las que presentaron mayor variabilidad fenotípica de entre todos los caracteres biométricos medidos en los machos, siendo éstas también más variables en los machos que en las hembras. Aunque la hiperalometría y una mayor varianza han sido frecuentemente utilizadas como argumento para apoyar la selección sexual como fuerza evolutiva, nuestros resultados sugieren que el peso y el dedo medio han sufrido procesos evolutivos diferentes. La competencia sexual entre machos es muy marcada en esta especie, y un mayor peso facilita el acceso a las hembras. Por ello, la selección sexual ha debido favorecer un incremento del peso hasta el límite impuesto por el beneficio derivado de seguir conservando la capacidad de vuelo. Por otro lado, como Otis tarda es un ave poco propensa a volar y que se desplaza fundamentalmente caminando, la hiperalometría del dedo medio ha debido desarrollarse por selección natural, como respuesta al enorme peso, para cumplir adecuadamente la función de soporte y mantenimiento del equilibrio.

We studied the genetic diversity of great bustards (Otis tarda) in Iberia and Morocco, the main stronghold of this globally endangered species. Samples were collected from 327 individuals covering most of the distribution range within the study area. Sequence variation in a 657 bp fragment of the mtDNA control region revealed 20 variable sites defining 22 haplotypes, two of them exclusive to Morocco. Genetic diversity showed marked regional differences (p = 0–0.53, h = 0–0.89). Multidimensional scaling analysis based on FST values showed a clear division between Morocco and the Iberian Peninsula, with no evidence of current gene flow between them. Our results suggest that Morocco, where few matrilines have persisted to present, was colonized from Iberia thousands of years ago. Last century reports suggest dispersal through Gibraltar, when the species was more abundant at both sides of the Strait but later population declines and the Strait’s barrier effect have favoured current genetic isolation. Within Iberia, only the most peripheral populations (Navarra, Aragon and Andalusia) differed significantly from the main ones in central Spain. The first two showed extremely low genetic diversity and are probably threatened by inbreeding depression. Diversity was higher in Andalusia, where three exclusive haplotypes were found, suggesting some degree of isolation from other populations. Andalusia and Morocco could be regarded as separate management units which hold a significant proportion of the current genetic diversity and thus deserve urgent conservation measures.

Radio tracking of 142 males captured at 44 leks in Spain showed that partial migration of great bustard males in summer is a widespread behaviour in many Iberian populations, in contrast to their previously assumed sedentariness. A variable number of males migrated immediately after mating to summering areas with lower temperatures and human population densities and more trees and rainfall levels than the breeding sites. Birds selected there fields with trees and sunflower crops which provided shade during the hottest midday hours and protective cover against predators. Males breeding in areas with higher July temperatures had a higher tendency to migrate, and males from hotter, southern regions migrated longer distances than those from milder, northern regions and showed a preferred northward direction. These results confirmed various predictions from the weather sensitivity hypothesis, suggesting that summer migration of great bustard males represents primarily an adaptation to escape the summer heat of most breeding areas in central and southern Iberia. The hypothesis that males migrated to benefit from higher food availability at the summering areas could not be rejected by our results. Finally, migrating males also gained more tranquillity during the postbreeding moult due to the lower human population density at the summering areas. Summer migration of Iberian great bustard males may thus be interpreted as a form of behavioural thermoregulation which has not been described for other Palaearctic populations of this species or for other bird species breeding in temperate latitudes.

Com les persones, els ordinadors també es fan grans, però en menys temps. A la Politècnica treballem per millorar el rendiment dels servidors i aconseguir, així, que triguin més a experimentar fallades.

Adaptive techniques based on machine learning and data mining are gaining relevance in self-management and self- defense for networks and distributed systems. In this paper, we focus on early detection and stopping of distributed flooding attacks and network abuses. We extend the framework proposed by Zhang and Parashar (2006) to cooperatively detect and react to abnormal behaviors before the target machine collapses and network performance degrades. In this framework, nodes in an intermediate network share infor- mation about their local traffic observations, improving their global traffic perspective. In our proposal, we add to each node the ability of learning independently, therefore reacting differently according to its situation in the network and local traffic conditions. In particular, this frees the administrator from having to guess and manually set the parameters distinguishing attacks from non-attacks: now such thresholds are learned and set from experience or past data. We expect that our framework provides a faster detection and more accuracy in front of distributed ooding attacks than if static filters or single-machine adaptive mechanisms are used. We show simulations where indeed we observe a high rate of stopped attacks with minimum disturbance to the legitimate users., Postprint (published version)

We present the Tester, a 100% Java benchmarking tool designed to accept a custom representation of a load schedule and reproduce it using distributed client machines in order to test a service. Our implementation is strongly based on a set of interfaces and pluggable implementations allowing for custom extensions. This project was realized at the Conrad Zuse Institut in Berlin, in a CoreGrid Research Exchange Program. One of the features of our application is the addition of the ZIB's Sminer Project Preferences library, a hierarchical data structure extracted from an XML configuration file, allowing for multiple customisation possibilities.

Un estudiante de primer curso de Ingeniería en Informática debe adquirir la capacidad de analizar y depurar códigos, tanto a alto nivel como en ensamblador. Este proceso requiere una participación activa por parte de los estudiantes, sobre todo en el laboratorio. Sin embargo, un entorno de laboratorio desconocido y la falta de conocimientos previos llevan a los alumnos a basar su aprendizaje en la realimentación (feedback) ofrecida por el profesor. Esta dependencia hace que los alumnos no utilicen el software de laboratorio para solucionar los problemas de teoría y trabajar de forma autónoma. Además, la mayoría de las preguntas de los estudiantes son siempre las mismas, y pueden ser resueltas de manera fácil y rápida. Sin embargo, el profesor no está disponible en todo momento, por lo que una pregunta que podía resolverse en segundos mantiene al estudiante atascado durante minutos, hasta que dispone del profesor. Para solucionar esta situación se ha desarrollado el entorno SISA-EMU, que permite comprobar rápidamente si una solución es correcta. Además incorpora un sistema de realimentación automático que orienta a los alumnos sobre los errores que han cometido. Con esta herramienta se fomenta que los alumnos trabajen de forma semiautónoma y obtengan un mayor provecho de los problemas realizados., Preprint

1 We investigated the causes of natal dispersal in four Spanish areas where 35 breeding groups of the polygynous great bustard Otis tarda were monitored intensively. A total of 392 juveniles were radio-tracked between 1991 and 2006 by ground and via aeroplane to avoid potential biases derived from the non-detection of long-distance dispersers. 2 We explored 10 explanatory variables that were related to individual phenotypic features, habitat and conspecific traits in terms of group size and breeding performance, and spatial distribution of available breeding groups. Probability of group change and natal dispersal distances were investigated separately through multifactorial analyses. 3 Natal dispersal occurred in 47·8% of the birds and median natal dispersal distance of dispersers was 18·1 km (range 4·97–178·42 km). Sex largely determined the dispersal probability, with 75·6% of males being dispersers and 80·0% of females being philopatric, in contrast to the general pattern of female-biased dispersal found in most avian species. 4 Both the frequency of natal dispersal and dispersal distances were affected by the spatial distribution of breeding groups. More isolated groups showed a higher proportion of philopatric individuals, the effect being more evident in males than in females. This implies a reduction in gene flow in fragmented populations, as most genetic exchange is achieved through male dispersal. Additionally, dispersers hatched in more isolated groups tended to exhibit longer dispersal distances, which increases the associated energetic costs and mortality risks. 5 The dispersal decision was influenced by the number of conspecifics in the natal group. The individual probability of natal dispersal was related inversely to the size of the natal group, which supports the balanced dispersal model and the conspecific attraction hypothesis. 6 Overall, our results provide a good example of phenotypic plasticity and reinforce the current view that dispersal is an