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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]

Multivariate analyses of the diet relationships within fish assemblages resulted in the recognition of five major feeding guilds in shallow (0–9 m) rocky- and soft-bottom habitats on the Swedish west coast. The two habitats had similar guilds that could be broadly described as piscivores, decapod feeders, copepod feeders and amphipod and mollusc feeders. The last guild on the rocky bottom was more strictly one of amphipod feeders, whereas the last guild on soft bottoms consisted of infauna feeders (mainly polychaetes and bivalves). A comparison of the diet of the entire fish assemblages showed that amphipods and gastropods were more prevalent as prey taxa on rocky bottoms, whereas bivalves and teleosts were more common on soft bottoms. A large proportion (12 out of 27 species) of the fish species investigated was found in both habitats. These fish species generally seemed to rely on the same major prey groups in the two habitats, but also included prey taxa characteristic for the habitat in which they resided. Sea trout Salmo trutta, mackerelScombrus scombrus , saithe Pollachius virens, whiting Merlangius merlangus and cod Gadus morhua were found to be the major piscivores in both the investigated habitats. Herring Clupea harengus and members of the family gobiidae were the most prevalent prey species for piscivores within the rocky- as well as the soft-bottom fish assemblage. A comparison of feeding modes suggested that the fish assemblage on rocky bottoms predominantly (60% of the food items) relied on food found in vegetation. On soft bottoms, the average distribution of food categories among fish species was 44% benthic, 35% pelagic and 21% vegetation-associated food items. [Copyright &y& Elsevier]

Juvenile chum Oncorhynchus keta and pink Oncorhynchus gorbuscha salmon change the composition of their visual pigments when they move from coastal waters to offshore in the Okhotsk Sea. Levels of the visual pigment rhodopsin were found to be high on the coast, while porphyropsin levels were high in offshore waters in both species. These facts suggest visual function may be similar, allowing them to coexist in the same sea area. Copyright 2002 The Fisheries Society of the British Isles. Published by Elsevier Science Ltd. All rights reserved. [Copyright &y& Elsevier]

We examined population traits of yellow American eels from nine sites with similar habitat characteristics in each of four rivers in Maine, U.S.A. Migrating silver eels were also collected to compare sex ratio, age and size at migration among the four rivers. Population density and biomass were not significantly different among rivers with mean ranges of 8.4–21.8 eels 100 m-2 and 380–1485 g m-2. Pairwise comparisons of the slopes of weight–length relationships of log transformed data (pooled data: intercept = -6.007, slope = 3.094, r2 = 0.99, and n = 3116) revealed no significant differences among rivers. Length–age relationships (pooled data: intercept = 87.826, slope = 23.444, r2 = 0.76, and n = 2325) also showed no statistically significant pairwise differences in slopes among rivers. In all rivers, sexual differentiation was complete by 270 mm total length and age eleven. The sex ratios of migrating silver eels were not correlated with yellow eel sex ratios among the four rivers. Mean age at migration among the four rivers was significantly different for males only, with a range of 1.3 years. Both sexes had some significant differences in size at migration among rivers, but the biological importance of the differences is tenuous (male range: 15 mm, female range: 36 mm). The yellow and silver eel population traits from these four rivers showed little variation when riverine habitat was isolated. Variations in traits appeared to be greater when eels from non-riverine habitats may have been present. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the significance of oral mucosal surfaces as a habitat of periodontopathic micro-organisms. For this investigation, 7 young adults were selected for an experimental gingivitis study. At the start of the experiment, bacterial samples were taken by means of a sterile swab from 4 oral mucosal surfaces: the buccal mucosa, the vestibular fold, the dorsum of the tongue and a tonsil. All individuals were asked to abstain from oral hygiene procedures in 1 quadrant of the mouth for a period of 23 days. At the end of this period, plaque samples were taken from 4 tooth surfaces by means of a sterile periodontal probe just coronal from the gingival margin. The study included evaluation of spirochetes and motile organisms by means of phase- contrast microscopy and of black-pigmented Bacteroides, Fusobacterium, Actinomyces, Actinobacillus actinomycetemcomitans and capnocytophaga by means of cultural studies. Results showed a relationship between the prevalence of motile organisms and black-pigmented Bacteroides in samples from both the mucosal surfaces and the 23-day-old plaque. In addition, a relationship was found between the presence of motile organisms on the dorsum of the tongue at the start of the experiment and their prevalence in the 23-day-old plaque. It was suggested that the dorsum of the tongue may function as a nidus for periodontopathic micro-organisms. [ABSTRACT FROM AUTHOR]

In multivoltine insects that oviposit and develop on short-lived plants, different herbivore generations across a growing season often exploit different plant species. Here, we compare the development time, pupal mass, and survival of two closely related oligophagous herbivore species on two species of brassicaceous plants that grow in different habitats and which exhibit little overlap in temporal growth phenology. In central Europe, the green-veined white butterfly, Pieris napi L., is bivoltine, whereas the small cabbage white butterfly, Pieris rapae L., has two to three generations a year. Moreover, P. napi is primarily found in moist, open (e.g., meadow), and forest habitats, whereas P. rapae prefers drier, open habitats. Both butterflies were reared on Garlic mustard (Alliaria petiolata), which is shade-tolerant and grows early in spring in forest undergrowth, and Black mustard (Brassica nigra), which prefers open disturbed habitats and is most common in summer. Both host plant species differ in other traits such as secondary chemistry. We hypothesized that, owing to habitat preference, P. napi would develop equally well on both plants but that P. rapae would perform better on B. nigra. The results provide partial support for this hypothesis, as both herbivores performed equally well on A. petiolata and B. nigra. However, there were differences in these parameters that were species-specific: on both plants P. rapae developed faster and had larger pupae than P. napi. Our results show that specialized herbivores can exploit different species of related plants that grow at different times of the season, enabling them to have multiple generations., (© The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Winter feeding of White-tailed Deer has become very common in northeastern North America. Food addition at feeding sites can modify the usual activity pattern of deer. Using telemetry, we compared home-range size and movements of nine deer that used feeding areas with those of eight animals that did not have access to artificial food. Winter home range size did not differ significantly between deer attending feeding sites (42 ha) and those which depended only on natural food (39 ha). Deer frequenting feeding areas tended to stay closer to feeders during the first half of the winter than the second, but this behavior did not affect their home range size. Artificial feeding of White-tailed Deer providing approximately one third of their food requirements did not change markedly their pattern of space use during a winter with average snowfall in a wintering area where competition for food was intense. [ABSTRACT FROM AUTHOR]

Female Canada Lynx (Lynx canadensis) use maternal dens from birth until the kits are weaned and foraging with their mothers. I inspected 39 den sites during a long-term study of lynx population dynamics in southwestern Yukon. Most dens were under deadfall debris in burns, which predominated in the study area. Blowdown debris, mature and shrubsubalpine fir trees, and willow shrub thickets were also used for denning in burned or unburned areas. Dens were generally located mid-slope and faced south or southwest. Dens were not re-used in subsequentyears. Den sites of neighboring females, and sites used by females in different years, were as close as 300 m. Females occasionally relocated dens even when not disturbed by the investigators. Den sites arean important habitat feature which, along with foraging habitat, cover and travel corridors, may enhance lynx recruitment. Den site availability should be taken into consideration when managing or assessingchanges to lynx habitats. [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]

Potential damage to crops after the Conservation Reserve Program is widespread. One probable result is the increased occurrence of soil-insect pests primarily wireworms (Coleoptera: Elateridae). The likelihood of wireworm problems in the Iowa Conservation Reserve Program wascompounded by the large amount of land enrolled in the program and the economic importance of corn, Zea mays L., the crop most often damaged by wireworms in the state. As a result, farmers need to consider pest management options that should include pest scouting. Wireworm presence/absence data from 1995 and 1996, and estimates of soil moisture from 89 Conservation Reserve Program fields were used to estimate variables useful for identifying where wireworms are more likely to occur. The most useful variables were a soil-moisture threshold of 17%and a moisture analysis that included meteorological data from only 1 yr before sampling occurred. These variables were coupled with a hydrologic model and embedded in a geographic information systems (GIS)framework. This computerized habitat model was run on the study area, Story County, Iowa, and generated a map indicating areas where wireworms were more likely to occur and where scouting should begin. Results of the model run indicate that most of Story County is suitable wireworm habitat and that there were areas considered highly favorable. The map generated by this computer model can be used as a guide fordirecting scouting within a field but does not identify areas where management tactics are necessary. The methodology used in this study is relatively simple, yet it performs the difficult task of combiningtime, space, and climatological variables to evaluate wireworm habitat over a landscape. Moreover, it demonstrates one application of GIStechnology in a discipline where the subject has characteristics that are inherently spatial. [ABSTRACT FROM AUTHOR]

The abundance of predatory hemipterans within 4 crops-soybean, Glycine max (L.); corn, Zea mays L.; tomato, Lycopersicum esculentum Miller; and tobacco, Nicotiana tabacum L.-was studied in small plots in 1992 and 1993. Predatory hemipteran populations varied among the crops despite the close proximity of the various crops. No predatory hemipteran was commonly observed in >2 crops, and nabids were associated with only 1. Three nabid species-Nabis roseipennis Reuter, Nabis americoferus Carayon, and Nabis rufusculus Reuter-were associated with soybean; only small numbers were found on the other crops. The anthocoridOrius insidiosus (Say) was abundant on soybean early in the season and became more abundant on corn as the season progressed. Geocoris punctipes (Say) was common in soybeans and tobacco, although nymphs were more abundant on soybean. Jalysus wickhami (Say) was found on tomatoes and tobacco and only rarely on the other crops. Predatory hemipterans from different families exhibited differences in crop associations. Implications of crop associations by predatory hemipterans are discussed. [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]

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.