Representaciones y resolución de problemas en Física

La intención de construir una teoría general de la cognición humana basada en un Único formato representacional ha mostrado ser, hasta el momento, una empresa demasiado ambiciosa. No obstante, en el intento de explicar ciertos fenómenos mentales involucrados en tareas cognitivas particulares, han surgido numerosos formatos representacionales en el ámbito de la Ciencia Cognitiva

Investigación en enseñanza de la Física y la formación de profesores: algunos elementos para la discusión

In the present work sorne data on a set of published communications in the minutes of researchers symposia the IX National Meeting on Physics Education, are presented to study the possibility of their incorporation to the teachers training.This first analysis tends to know, for example: trends of the current investigation, characteristic of the communications, educational leve! of the investigated subjects, and dominant methodological and theoretical aspects.It is a substantially descriptive study andas such intends to detail sorne aspects of the analyzed projects. The presented result ha ve to be understood as data that make possible a reflection to reinforce or reorient investigation lines and to contribute to the discussion that help the definition of investigation policies in the area. In so much the results are not detached from the community that produces them, the one which at the same time is vehicle of their findings, we find that the incorporation of the investigation in the physics teachers institutions must ha ve, without doubt, sorne relationship to the characteristics of the accomplished projects.</p

La resolución de problemas en física y su representación : un estudio en la escuela media

The present study explores: a) the relationship between certain characteristics of physics (problem statements and the internal representation that students form after reading the statement; b) the correlation between this representation and the equation generation stage. Seventeen-year-old students of secondary school from Madrid were taken as an accidental sample (N = 189). Certain characteristics of these statements were observed to be favourable instances to solve the problem. Possible implications for the instruction were analysed

Genetic colour polymorphism is associated with avian malarial infections

Peer reviewe

Contradiction in conservation of island ecosystems: Plants, introduced herbivores and avian scavengers in the Canary Islands

Introduction of alien herbivores in sensitive island systems has resulted in massive effects on vegetation cover, floristic richness and composition of communities; some species can be even totally extirpated by grazing pressure. Goats Capra hircus and wild rabbits Oryctolagus cuniculus were introduced in the Canary Islands around 500 B.C. Barbary ground squirrels Atlantoxerus getulus were introduced in 1967. Traditional extensive livestock exploitations have been maintained to the present but in the last decades the number of goats has sharply increased up to densities of 53 heads/km2. Overgrazing and trampling have heavily affected eleven island endemic plant species. Some populations have been reduced to less than 10 viable individuals. On the other hand, goat carcasses and wild rabbit and squirrel populations help to maintain populations of three endangered endemic subspecies of birds. This conflict presents important economic and social ramifications: whereas public funds (mainly through European LIFE projects) are devoted to conservation of plant and avian endemic taxa, the number of goats increases rapidly thanks to subventions derived from the European Common Agricultural Policy (CAP). Similar conflicts are apparent in other Mediterranean Basin insular systems. It is urgently necessary to harmonize farming and conservation objectives in the Canary Islands. The impact of goats on the vegetation should be minimized through limitation of grazing in sensitive areas with high degree of endemism. Creation of 'vulture restaurants' may reduce the dependence of scavengers on extensive livestock exploitations. We recommend a careful study of ecological relationships within island communities where non-native species are susceptible of playing a keystonrole as occurs in the Mediterranean Basin archipelagos. © Springer 2006.Peer Reviewe

Genetic colour polymorphism is associated with avian malarial infections

Peer reviewe

Editorial: Factors Affecting Host Selection by Mosquitoes: Implications for the Transmission of Vector-Borne Pathogens

Project PGC2018- 095704-B-I00 from the Spanish Ministry of Economy and Competition and from the European Regional Development Fund (FEDER

Ecological specialization to fluctuating resources prevents long-distance migratory raptors from becoming sedentary on islands

[Background]: The adaptive transition between behavioral strategies, such as the shift from migratoriness to sedentariness, remains an outstanding question in evolutionary ecology. Density-dependent variation in the age of first breeding has been proposed as a feasible mechanism through which long-lived migratory birds with deferred sexual maturity should become sedentary to persist on islands. Although this pattern seems to hold for most raptors and herons, a few exceptions have been identified. One of these exceptions is the Eleonora's falcon, a long-distance migratory bird, which shows one of the most peculiar adaptations in the timing of reproduction and food requirements among raptors. [Methodology/Principal Findings]: Here, we compiled data concerning demography, banding recoveries and satellite tracking of Eleonora's falcons to discuss likely explanations for the exceptional behavior of this insular long-distance migratory species. [Conclusions/Significance]: New data reveal that Eleonora's falcons do return to the natal colonies in their first year and young birds are able to breed. However, in contrast to previous hypothesis, the highly specialized strategy of this and other ecologically similar species, as well as the virtual lack of food during winter at breeding areas prevent them from becoming sedentary on islands. Although the ultimate mechanisms underlying the process of sedentarization remain poorly understood, the evidence provided reveal the existence of important trade-offs associated with ecological specialization that may become particularly relevant in the present context of global change.L.G. is supported by the FP7-REGPOT 2010-1 EcoGenes Project (Grant No. 264125). P.L.-L. is supported by a ‘Juan de la Cierva’ postdoctoral grant from the Spanish Ministry of Economy and Competitiveness (reference JCI-2011-09588). U.M. is supported by a FPU grant from the Spanish Ministry of Education (reference AP2008-0947). R.L. has a postdoctoral grant (reference 10/12-C) co-funded by ‘Consejería de Educación y Ciencia’ (JCCM) and the European Social Fund.Peer Reviewe

Do mosquitoes transmit the avian malaria-like parasite Haemoproteus? An experimental test of vector competence using mosquito saliva

[Background] The life-cycle of many vector-borne pathogens includes an asexual replication phase in the vertebrate host and sexual reproduction in the insect vector. However, as only a small array of parasites can successfully develop infective phases inside an insect, few insect species are competent vectors for these pathogens. Molecular approaches have identified the potential insect vectors of blood parasites under natural conditions. However, the effectiveness of this methodology for verifying mosquito competence in the transmission of avian malaria parasites and related haemosporidians is still under debate. This is mainly because positive amplifications of parasite DNA in mosquitoes can be obtained not only from sporozoites, the infective phase of the malaria parasites that migrate to salivary glands, but also from different non-infective parasite forms in the body of the vector. Here, we assessed the vectorial capacity of the common mosquito Culex pipiens in the transmission of two parasite genera.[Methods] A total of 1,560 mosquitoes were allowed to feed on five house sparrows Passer domesticus naturally infected by Haemoproteus or co-infected by Haemoproteus/Plasmodium. A saliva sample of the mosquitoes that survived after 13 days post-exposure was taken to determine the presence of parasite DNA by PCR.[Results] Overall, 31.2% mosquito’s head-thorax and 5.8% saliva samples analysed showed positive amplifications for avian malaria parasites. In contrast to Haemoproteus DNA, which was not found in either the body parts or the saliva, Plasmodium DNA was detected in both the head-thorax and the saliva of mosquitoes. Parasites isolated from mosquitoes feeding on the same bird corresponded to the same Plasmodium lineage.[Conclusions] Our experiment provides good evidence for the competence of Cx. pipiens in the transmission of Plasmodium but not of Haemoproteus. Molecular analyses of saliva are an effective method for testing the vector competence of mosquitoes and other insects in the transmission of vector-borne pathogens.This study was funded by projects CGL2012-30759 and CGL2015-65055-P from the Spanish Ministerio de Economia y Competitividad and European Regional Development’s funds (FEDER). We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). R.G.L. was supported by a FPI grant (BES-2013-065274), J.M.P. by a Juan de la Cierva contract, L.G. by a contract under the Excelence Projects from Junta de Andalucía (RNM-7800) and J.Y. by a grant from China Scholarship Council.Peer reviewe

Seasonal grouping dynamics in a territorial vulture: ecological drivers and social consequences

Despite widespread occurrence of seasonal sociality among animals, little is still known about the social drivers and populationlevel social implications of seasonal grouping behaviours, especially in birds. Here, we studied the combined effects of ecological and social factors on seasonal grouping patterns in a sedentary population of Egyptian vultures living on the Eastern Canary Islands. We focussed on the social significance of large-scale gatherings taking place outside the breeding season at a highly preferred feeding station and a nearby temporary roost. Group sizes at this feeding patch followed a strong seasonal pattern characterized by distinct monthly changes in group composition, according to sex, age and territorial status. In between reproductive periods, vulture numbers at the feeding station may reach up 50% of the total population on a single day. GPS-tracking showed that this increase in vulture numbers was in part due to a shift in foraging range towards the centre of Fuerteventura by low-ranked territorial birds breeding in remote areas. During this period, vultures may spend on average 30% of their monthly time in a social gatherings context, depending on social status. We show that seasonal grouping patterns are shaped by the complex interplay between ecological factors (reproductive constraints, resource seasonality, food predictability), age-specific traits and social competitive processes, while social attraction may be an important additional component. We propose that for facultative social foragers living in highly despotic territorial systems, collective foraging may be of particular relevance regarding the development of hierarchical social relations and maintenance of population-level social cohesionTvO received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. “SocForVul 659008During writing, LG was supported by a Marie Sklodowska-Curie Fellowship of the European Commission (grant number: 747729 “EcoEvoClim”)MG-A was supported by a contract from “Programa de FPU del Ministerio de Educación, Cultura y Deporte” (FPU13/05429)The long-term monitoring of the vulture population has been funded by the projects REN 2000–1556 GLO, CGL2004-00270/BOS, CGL2009-12753-C02-02, CGL2012-40013-C02-01 and CGL2015-66966-C2-1-2-R (Spanish Ministry of Economy and Competitiveness and EU/FEDER)Further support was provided by the Cabildo Insular de Fuerteventura and the Dirección General de Protección de la Naturaleza (Viceconsejería de Medio Ambiente, Canarian Government)