Search results for "PARUS"
showing 10 items of 134 documents
Data from: Inter-annual variation and long-term trends in proportions of resident individuals in partially migratory birds
2016
Partial migration – a part of a population migrates and another part stays resident year-round on the breeding site – is probably the most common type of migration in the animal kingdom, yet it has only lately garnered more attention. Theoretical studies indicate that in partially migratory populations, the proportion of resident individuals (PoR) should increase in high latitudes in response to the warming climate, but empirical evidence exists for few species. We provide the first comprehensive overview of the environmental factors affecting PoR and the long-term trends in PoR by studying 27 common partially migratory bird species in Finland. The annual PoR values were calculated by divid…
Enteromyxum leei (Myxozoa: Myxosporea) infection in gilthead sea bream (Sparus aurata): Immune-related studies
2013
La presente tesis doctoral estudia diversos aspectos de la enteromixosis de la dorada, relacionados principalmente con la transmisión y la caracterización del parásito, con los factores que afectan a su establecimiento en el hospedador y a la interacción parásito-hospedador, y con la respuesta inmunitaria inducida por el parásito. En primer lugar, se desarrolló un nuevo método de transmisión de E. leei, que mejora los resultados obtenidos por los hasta ahora disponibles. El parásito se transmitió con éxito a doradas mediante intubación por vía anal de raspados intestinales de peces infectados. Con este método, se consiguió una infección más rápida y extensa que por efluente y por cohabitaci…
Microstructures in shells of the freshwater gastropod Viviparus viviparus: a potential sensor for temperature change?
2013
Abstract Mollusk shells contain a plethora of information on past climate variability. However, only a limited toolkit is currently available to reconstruct such data from the shells. The environmental data of some proxies (e.g. Sr/Ca ratios) is obscured by physiological effects, whereas other proxies, such as δ 18 O, simultaneously provide information on two or more different environmental variables. The present study investigates whether microstructures of the freshwater gastropod Viviparus viviparus provide an alternative means to reconstruct past water temperature. Cold and highly variable temperature regimes resulted in the precipitation of highly unordered first-order lamellae of simp…
Exploitation competition between hole‐nesters ( Muscardinus avellanarius , Mammalia and Parus caeruleus , Aves) in Mediterranean woodlands
2005
Data from a long-term study (1993-2003) using artificial nest-boxes, were analysed to examine competition for nesting between blue tit Parus caeruleus and common dormouse Muscardinus avellanarius in Sicily. Occupation rates and the reproductive biology of the blue tit in sample woodlots outside the distribution area of the common dormouse were used as a control in sample areas where the two species were syntopic. A selection test showed that the two species, when living in syntopy, actively chose the small nest-boxes, thus overlapping in the use of the same spatial resource. The experimental exclusion of the common dormouse from nest-boxes caused an increase of blue tit occupation rate. Onc…
Predator mimicry, not conspicuousness, explains the efficacy of butterfly eyespots
2015
Large conspicuous eyespots on butterfly wings have been shown to deter predators. This has been traditionally explained by mimicry of vertebrate eyes, but recently the classic eye-mimicry hypothesis has been challenged. It is proposed that the conspicuousness of the eyespot, not mimicry, is what causes aversion due to sensory biases, neophobia or sensory overloads. We conducted an experiment to directly test whether the eye-mimicry or the conspicuousness hypothesis better explain eyespot efficacy. We used great tits ( Parus major ) as model predator, and tested their reaction towards animated images on a computer display. Birds were tested against images of butterflies without eyespots, wi…
Les objets des disparus. Exhumations et usages des traces matérielles de la violence de masse
2017
International audience; Distribution électronique Cairn.info pour UMR Sirice. © UMR Sirice. Tous droits réservés pour tous pays. La reproduction ou représentation de cet article, notamment par photocopie, n'est autorisée que dans les limites des conditions générales d'utilisation du site ou, le cas échéant, des conditions générales de la licence souscrite par votre établissement. Toute autre reproduction ou représentation, en tout ou partie, sous quelque forme et de quelque manière que ce soit, est interdite sauf accord préalable et écrit de l'éditeur, en dehors des cas prévus par la législation en vigueur en France. Il est précisé que son stockage dans une base de données est également int…
Does Arsenic Contamination Affect DNA Methylation Patterns in a Wild Bird Population? : An Experimental Approach
2021
Pollutants, such as toxic metals, negatively influence organismal health and performance, even leading to population collapses. Studies in model organisms have shown that epigenetic marks, such as DNA methylation, can be modulated by various environmental factors, including pollutants, influencing gene expression, and various organismal traits. Yet experimental data on the effects of pollution on DNA methylation from wild animal populations are largely lacking. We here experimentally investigated for the first time the effects of early-life exposure to environmentally relevant levels of a key pollutant, arsenic (As), on genome-wide DNA methylation in a wild bird population. We experimentall…
In vitro modulation of cytokines by pathogens and probiotics on the skin of Gilthead Seabream (Sparus aurata)
2016
Gilthead seabream (Sparus aurata) is the only species of the Sparidae family currently bred on a large scale. As one of the most important species on Mediterranean aquaculture. For this main reason, the knowledge of its immune system and their alterations it is crucial to avoid economic losses worldwide. Fish are in intimate contact with their environment and defending itself by a complex system of innate defence mechanisms, that is divided into physical barriers, cellular and humoral components. The skin as a physical barrier seems to be central to protection from pathogens such as Photobacterium damselae ssp. piscicida. Probiotics are microorganisms (usually bacteria) that promote differe…
The Role of Spatial Exploration and Territoriality in Establishing Gilthead Seabream (Sparus aurata) Hierarchies, and Their Effects upon Underlying S…
2023
Territoriality, spatial exploration and social hierarchy are strictly related behaviors in gregarious fishes, and are often under-appreciated in farms where the individuals are confined within crowded spaces. In this study, we investigated the role of spatial exploration, elucidating the importance of time upon forming the social organization, and the role of the territoriality in gilthead seabream (Sparus aurata), using two experimental approaches. In the first approach, three fish were placed sequentially in the aquarium with an interval of two days (sequential model), while in the second (simultaneous model), two fish were simultaneously placed in an aquarium divided by a barrier which w…
Patrones de incubación y eclosión del Carbonero Común Parus major en un ambiente mediterráneo: causas y consecuencias
2013
Objetivos generales: Los principales objetivos de esta tesis son describir los patrones de incubación y eclosión de una población de carbonero común Parus major en un ambiente mediterráneo, profundizar en algunas de las causas que afectan a dichos patrones, centrándonos sobre todo en las características del nido, y describir sus posibles consecuencias en el desempeño reproductor. Hipótesis general: Las características parentales, las del nido, y las condiciones ambientales pueden afectar a la duración de los periodos de incubación y eclosión, teniendo consecuencias en el desempeño reproductor. Para poder alcanzar los objetivos generales, hemos identificado varios objetivos particulares, agr…