La Guerra Civil española en el cómic de autoría femenina

En este trabajo se estudia, desde la perspectiva de género, la representación que el cómic más contemporáneo está llevando a cabo sobre la guerra civil española. Para ello, el ensayo comienza repasando brevemente los cómics de autoría masculina que tienen a mujeres como protagonistas, para pasar, en una segunda parte, a analizar más detenidamente las novelas gráficas de autoría femenina Todo lo que nos contaron nuestros abuelos (Cachete Jack, 2012), Winnipeg: el barco de Neruda (Laura Martel, 2014) y Tante Wussi (Katrin Bacher y Tyto Alba, 2015). El análisis textual de estas obras mostrará que el cómic de autoría femenina se caracteriza por ofrecer una reflexión autoconsciente sobre la importancia de la transmisión de la memoria.

An attempt to determine the size of the Common Barn-owl’s (Tyto alba) hunting area based on its prey composition

The relative abundance of small mammal species detected from Common Barn-owl pellets reflects the landscape structure and habitat pattern of the owl’s hunting area, but it is also affected by the size of the collected pellet sample and the size of the supposed hunting area. The questions arise: how many pellets should be collected and analyzed as well as how large hunting area should be taken into consideration in order to reach the best correspondence between the owl’s prey composition and the distribution of habitats preferred by small mammals preyed in supposed hunting areas? For this study, we collected 1045 Common Barn-owl pellets in a village in southern Hungary. All detected small mammal species were classified into functional groups (guilds) preferring urban, open, forest and wetland habitats. The proportion of functional groups was compared to the proportion of these habitats around the pellet collection site within circles of one, two, and three km radius. Saturation curves showed that at least 300 pellets or ca. 600 mammalian remains are required for the detection of the 19 small mammal species. The share of small mammals detected in the prey and their functional groups according to their habitat preference showed an increasing consistency with the distribution of real habitats in the potential hunting area of a radius of 3 km around the owl’s breeding or resting place.

Genomic bases of insularity and ecological divergence in barn owls (Tyto alba) of the Canary Islands

Islands, and the particular organisms that populate them, have long fascinated biologists. Due to their isolation, islands offer unique opportunities to study the effect of neutral and adaptive mechanisms in determining genomic and phenotypical divergence. In the Canary Islands, an archipelago rich in endemics, the barn owl (Tyto alba) is thought to have diverged into a subspecies (T. a. gracilirostris) on the eastern islands, Fuerteventura and Lanzarote. Taking advantage of 40 whole-genomes and modern population genomics tools, we provide the first look at the origin and genetic makeup of barn owls of this archipelago. We show that the Canaries hold diverse, long-standing and monophyletic populations with a neat distinction of gene pools from the different islands. Using new method, less sensitive to structure than classical FST, to detect regions involved in local adaptation to the insular environment, we identified a haplotype-like region likely under positive selection in all Canaries individuals. Genes in this region suggest morphological adaptations to insularity. In the eastern islands, where the subspecies T. a. gracilirostris is present, genomic traces of selection pinpoint signs of locally adapted body proportions and blood pressure, consistent with the smaller size of this population living in a hot arid climate. In turn, genomic regions under selection in the western barn owls from Tenerife showed an enrichment in genes linked to hypoxia, a potential response to inhabiting a small island with a marked altitudinal gradient. Our results illustrate the interplay of neutral and adaptive forces in shaping divergence and early onset speciation.

Diet of sympatric Barn Owls Tyto alba and Short-eared Owls Asio flammeus in an agricultural landscape in south-east Spain

The diets of the Barn Owl Tyto alba and the Short-eared Owl Asio flammeus have been extensively studied worldwide over the past few years, especially on the Iberian Peninsula. Nevertheless, very few studies have examined the diets and the trophic niche overlap in areas where these two raptor species occur in sympatry. As such, in this study we compared the diets of the Barn Owl and the Short-eared Owl inhabiting agricultural landscapes of the Vega de Granada, south-east Spain, based on pellet analysis. The diets were very similar, as both owls preyed mainly on small mammals, the Algerian Mouse Mus spretus being the prey most commonly found in pellets from both species. Although the diet of the Barn Owl was more diverse than that of the Short-eared Owl, the food niche overlap was very high, thus indicating a low interspecific trophic segregation. Despite the similarities between both diets, the frequency of the Mediterranean Pine Vole Microtus duodecimcostatus was much higher in pellets from the Barn Owl, thus suggesting that the Barn Owl may exert pest control in years when the Mediterranean Pine Vole occurs in high numbers.

When the barn-owl feasted on bats, an approach to taphonomic analysis

Small vertebrates are a key proxy for paleoenvironmental and paleoclimatic reconstruction, but a previous taphonomic analysis of the paleontological assemblage is needed before facing this kind of approach. Works concerning taphonomy of preyed small vertebrates are abundant in the literature, but chiropters are not usually included as they are only rarely predated. Here we analysed the content of two barn-owl (Tyto alba) pellets that exclusively contained bat remains. Our aim is to assess the effects of digestion inflicted by this predator on certain bat skeletal elements, specifically mandibles and lower teeth. All bat remains were assigned to Pipistrellus sp. They mostly presented slight alteration of the mandible and non-altered enamel, which is an expected result based on previous literature concerning this type of predator. Nevertheless, a few specific specimens showed much more intense alteration. This is most probably due to predator-related factors, although a higher degree of age-related tooth-wear in a specific bat cannot be dismissed.

Prótesis 3D para corregir eje corporal y equilibro en lechuza de campanario y cernícalo americano

La amputación de miembros pélvicos en aves rapaces, debe ser evaluada con detenimiento y considerada como el último recurso para salvar la vida del ave, debido a que posterior a la amputación, pueden derivarse una serie de factores degenerativos, como la alteración de eje corporal, distribución inadecuada del peso corporal y pododermatitis. Una buena alternativa para contrarrestar estos problemas, es el uso de prótesis, que busquen recuperar el eje corporal y mantener una buena postura en el ave. El uso de impresoras 3D para este tipo de proyectos, ofrece una alternativa más accesible y sencilla debido a su versatilidad tanto en diseño como en materiales. El presente proyecto pone a prueba el diseño de una prótesis 3D y documenta la corrección de eje corporal e incorporación de la prótesis en las actividades diarias de un cernícalo americano (Falco sparverius) y una lechuza de campanario (Tyto alba), ambas con una amputación tibiotarsal en su tercio distal. A pesar de que la utilización de prótesis no permite la reintroducción de las aves al medio ambiente, ofrece una oportunidad para integrar dichas aves en programas de conservación, tales como reproducción en cautiverio o educación ambiental.

Small mammals from barn owl Tyto alba pellets in a Mediterranean agroforestry landscape of central Italy

In order to investigate diversity patterns and similarities in the small mammal communities of an agroforestry landscape in western central Italy (Maremma of Lazio), we analyzed, in a multivariate setting (Cluster analysis, DCA-Detrended Correspondence Analysis), the prey content of barn owl Tyto alba pellets collected along one year in five sampling sites. Small mammal communities were composed by guilds typical of habitats included in agroforestry landscapes (croplands and mosaics, forests and ecotones, wet habitats and synanthropic ones). Since landscape matrices were characterized almost everywhere by croplands, typical agro-ecosystem species (Apodemus cfr. sylvaticus, Microtus savii, Mus domesticus and Soricidae) dominated in the majority of the collecting sites. The statistical analyses show how small changes in land use and cover can explain the faunal differences between sites, with the occasional presence of Arvicola italicus in wet habitats, and of Muscardinus avellanarius and Sorex samniticus in sites dominated by forest or agroforestry ecotones. Communities recorded in sites characterized by wet and forest habitats showed a higher distance from the others, dominated by croplands. Communities occurring in landscapes with the lowest habitat diversity showed also the lowest species diversity.

Descripción morfológica de la musculatura del miembro pélvico de un ejemplar de lechuza común (Tyto alba)

El objetivo de este estudio fue describir la musculatura de los miembros pélvicos de un ejemplar de lechuza común (Tyto alba). El espécimen cuenta con músculos potentes, con predominio en el desarrollo de los músculos flexores sobre los extensores. De manera general, existe similitud con la musculatura descrita en otras aves, especialmente rapaces; sin embargo, es importante destacar algunas diferencias, como por ejemplo, el m. iliofibular se encuentra bien desarrollado y se ubica caudal y superficial al m. iliotibial lateral; el m. femorotibial posee solo dos cabezas; los ms. ambiens y fibular largo no se observaron en el ejemplar estudiado, pero se observó el m. flexor lateral del muslo. El m. flexor digital largo posee solo una cabeza; los ms. perforantes y perforados se encuentran altamente fusionados y el m. extensor largo del dedo I presenta una pequeña cabeza muscular.

Exogenous corticosterone and melanin-based coloration explain variation in juvenile dispersal behaviour in the barn owl (Tyto alba)

Natal dispersal affects many processes such as population dynamics. So far, most studies have examined the intrinsic and extrinsic factors that determine the distance between the place of birth and of first breeding. In contrast, few researchers followed the first steps of dispersal soon after fledging. To study this gap, we radio-tracked 95 barn owl nestlings (Tyto alba) to locate their diurnal roost sites from the fledging stage until December. This was used to test whether the age of nest departure, post-fledging movements and dispersal distance were related to melanin-based coloration, which is correlated to fitness-related traits, as well as to corticosterone, a hormone that mediates a number of life history trade-offs and the physiological and behavioural responses to stressful situations. We found that the artificial administration of corticosterone delayed the age when juveniles left their parental home-range in females but not in males. During the first few months after fledging, longer dispersal distances were reached by females compared to males, by individuals marked with larger black feather spots compared to individuals with smaller spots, by larger individuals and by those experimentally treated with corticosterone. We conclude that the onset and magnitude of dispersal is sensitive to the stress hormone corticosterone, melanin-based coloration and body size.