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Colour variability is largely widespread in the animal world as it is tightly associated with fitness and survivorship. Therefore, the drivers and implications of such variability have been of great interest for zoologists in the past decades. Reptiles are excellent models to investigate colour variations and expression under different conditions. Here, we focused on melanism occurrence in the two main lineages of Hierophis viridiflavus at the scale of the species distribution, by extracting available data from iNaturalist, a citizen science network, with the aim of detecting any pure effect of climate or local habitat on colour expression. Our analyses highlighted that habitat does not explain differences in phenotypes, whereas marked effects of geographic and climatic variables were detected. However, the observed climatic effects could be a proxy of the geographical distribution of the two groups, and thus the high occurrence of bright colourations in western populations of the eastern lineage could be addressed to an ongoing event of asymmetric gene flow in contact zones. The current distribution of phenotypes could be the outcome of the evolutionary history of the species combined with the geological history of the Mediterranean region. This investigation, though, is only preliminary and molecular analyses on highly variable regions of the genome are mandatory to address this issue. [ABSTRACT FROM AUTHOR]

Este trabajo, mediante el uso de técnicas de investigación cualitativas -entrevistas semi-estructuradas a personas dependientes, cuidadores formales e informales y empleados públicos, privados o del tercer sector-, tiene como objetivo analizar las diferencias y similitudes existentes en las posiciones discursivas sobre cómo se efectúa la provisión de cuidados a los mayores dependientes en función de hábitat de residencia. Los resultados muestran que la inexistencia o inadecuación de recursos formales en los municipios rurales origina relatos que resaltan el peso de las atenciones familiares precisadas por los mayores dependientes. A su vez, la tradicional red informal de cuidados se percibe como debilitada en las zonas rurales debido al envejecimiento, los procesos migratorios campo-ciudad y las transformaciones sociales, familiares y culturales acontecidas desde el último tercio del siglo XX.

La Carta Medellín fue el documento oficial de conclusiones que quedó como testimonio de las sesiones correspondientes al Séptimo Foro Urbano Mundial que tuvo lugar en Medellín entre el 5 y el 9 de abril pasados, organizado por ONU-Hábitat en alianza con la Alcaldía de Medellí­n y el Ministerio de la vivienda. El texto de 170 páginas, se supone, recoge los insumos más importantes de los diálogos, asambleas y mesas redondas que tuvieron lugar en el marco de ese imponente evento que movilizó decenas de miles de visitantes y millones de dólares en financiación.

Effective assessment of biodiversity in cities requires detailed vegetation maps.To date, most remote sensing of urban vegetation has focused on thematically coarse landcover products. Detailed habitat maps are created by manual interpretation of aerialphotographs, but this is time consuming and costly at large scale. To address this issue, wetested the effectiveness of object-based classifications that use automated imagesegmentation to extract meaningful ground features from imagery. We applied thesetechniques to very high resolution multispectral Ikonos images to produce vegetationcommunity maps in Dunedin City, New Zealand. An Ikonos image was orthorectified and amulti-scale segmentation algorithm used to produce a hierarchical network of image objects.The upper level included four coarse strata: industrial/commercial (commercial buildings),residential (houses and backyard private gardens), vegetation (vegetation patches larger than0.8/1ha), and water. We focused on the vegetation stratum that was segmented at moredetailed level to extract and classify fifteen classes of vegetation communities. The firstclassification yielded a moderate overall classification accuracy (64%, κ = 0.52), which ledus to consider a simplified classification with ten vegetation classes. The overallclassification accuracy from the simplified classification was 77% with a κ value close tothe excellent range (κ = 0.74). These results compared favourably with similar studies inother environments. We conclude that this approach does not provide maps as detailed as those produced by manually interpreting aerial photographs, but it can still extract ecologically significant classes. It is an efficient way to generate accurate and detailed maps in significantly shorter time. The final map accuracy could be improved by integrating segmentation, automated and manual classification in the mapping process, especially when considering important vegetation classes with limited spectral contrast.

Esta contribución propone una síntesis sobre la Primera Edad del Hierro en la región de Bazas. Además de una revisión de la documentación arqueológica, se hace una reflexión sobre aspectos culturales, sociales y de geografía humana.

The decline of biodiversity with latitude has received great attention, but both the concise pattern and the causes of the gradient are under strong debate. Most studies of the latitudinal gradient comprise only one or few organism types and are often restricted to certain region or habitat types. To test for significant variation in the gradient between organisms, habitats, or regions, a meta-analysis was conducted on nearly 600 latitudinal gradients assembled from the literature. Each gradient was characterized by two effect sizes, strength (correlation coefficient) and slope, and additionally by 14 variables describing organisms, habitats, and regions. The analysis corroborated the high generality of the latitudinal diversity decline. Gradients on regional scales were significantly stronger and steeper than on local scales, and slopes also varied with sampling grain. Both strength and slope increased with organism body mass, and strength increased with trophic level. The body mass-effect size relation varied for ecto- versus homeotherm organisms and for different dispersal types, suggesting allometric effects on energy use and dispersal ability as possible mechanisms for the body mass effect. Latitudinal gradients were weaker and less steep in freshwater than in marine or terrestrial environments and differed significantly between continents and habitat types. The gradient parameters were not affected by hemisphere or the latitudinal range covered. This analysis is the first to describe these general and significant patterns, which have important consequences for models aiming to explain the latitudinal gradient. [ABSTRACT FROM AUTHOR]

Mountains occupy only 3% of Poland. They are the northern part of the European arc of the Carpathian and Sudety Mountains, extending ;about 700km along the southern Polish border. They are of medium height (about 1500m, maximum 2600m a.s.l.), and have diversified climate, geology, soils, vegetation, and anthropogenic impacts. The forest vegetation of the Sudety and Carpathian Mountains form three elevational zones. Forests occur in the foothills (as high as about 600 m a.s.l.),the lower mountain forest zone (as high as about 1250m a.s.l.) and the upper montane forest zone (as high as 1500m a.s.l.). The original,lower mountain forests consisted mainly of fir (Abies alba Mill.) and beech (Fagus sylvatica L.), while upper montane forests contained spruce (Picea abies (L:,) Karst.). Centuries of economic activity havechanged the species composition of mountain forests. Spruce has increased considerably, and the percentage of fir and beech has decreasedsignificantly. In the Sudety and western part of the Carpathians spruce is the most prevalent (as high as 83%), while in the eastern partof the Carpathians it does not exceed 10%. The percentage of beech in the Sudeten and western Carpathian forests is less than 20%, while it is about 40% in the eastern part of the Carpathians. Severe weather conditions, frequently poor habitats, and improper management and considerable air pollution occurring in the past 50 years, followed bye infestations of primary and secondary insects and spread of parasitic fungi, have led to considerable destruction of these mountain forests. According to forecasts the area of totally destroyed and severely damaged mountain forests will increase considerably through 2010. Deterioration of forest health will proceed from west to east. Protection of forest health against deterioration requires reduction of industrial emissions, changing existing forests into genotypes that are less sensitive to air pollution and more compatible with local habitats, an [ABSTRACT FROM AUTHOR]

Search effort is undirected when a forager has a stereotypical searching behavior that results in fixed encounter rates with its prey (e.g. diet choice models), and is directed when the forager can bias itsencounter with a 'chosen' prey. If the bias is complete, search is totally directed (e.g. habitat selection models). When the bias is incomplete (i.e. search modes are not exclusive to a single prey type), search is partially directed. The inclusion of a prey type in the diet is then the result of two decisions: (1) which prey to search for and (2) which prey to handle. The latter decision is determined by theratio of energy to handling time and the abundance of the preferred prey. The former decision is a function of the encounter probabilities and densities of all potential prey types in addition to their ratio of energy to handling time. Assuming two prey types, there are three distinct behavioral strategies: (1) search for the preferred prey/forage selectively; (2) search for the preferred prey/forage opportunistically; and (3) search for the non-preferred prey/forage opportunistically. If prey are depletable (i.e. prey occur in resource patches), the forager may switch search modes such that prey are depleted to the point where the marginal values of the search modes are equalized. [ABSTRACT FROM AUTHOR]