Search results for " history"
showing 10 items of 5953 documents
Competition for resources is ameliorated by niche differentiation between Solidago virgaurea life-history stages in the Arctic
2016
Aims Competition has been shown to modify the niche breadth of coexisting species, but within-species interactions have received little attention. Establishing small juvenile individuals and established, larger, sexually reproducing adult individuals represent two life-history stages within species. We investigated the nitrogen and carbon resource use of adult and juvenile individuals and similarity of symbiotic fungal community composition in these two plant life stages. We used the plant Solidago virgaurea growing in a simplified system in the low Arctic as model species. Methods Isotopic signatures (foliar δ15N and foliar δ13C) were analysed to characterize nitrogen acquisition and water…
Potential for managing life history diversity in a commercially exploited intermediate predator, the goldsinny wrasse (Ctenolabrus rupestris)
2019
Abstract Small-bodied wrasse species are important for structuring coastal marine ecosystems but are also increasingly harvested as parasite cleaners on farmed salmon. Identifying management regulations that will support long-term sustainability of wrasse fisheries is challenging, because there is still limited knowledge about the impacts of fisheries on the demography of these intermediate predators in their natural environments. To this end, we studied individual growth histories of goldsinny wrasse (Ctenolabrus rupestris) at a fine spatial scale across replicated marine protected areas (MPAs) and areas open to commercial harvesting on the Norwegian coast. The MPAs were established 1–7 ye…
Growth sites of polypores from quantitative expert evaluation: Late-stage decayers and saprotrophs fruit closer to ground
2017
Abstract Life history traits are key to why species occur when and where they do and how their populations will respond to environmental changes. However, dispersal-related traits of fungi are generally poorly known. We studied how spore release height from the ground, an important determinant of airborne dispersal, is connected to other traits in polypores. We collected expert evaluations of fruit body growth sites for 140 species and found that experts generally provided consistent estimates of height above the ground. Height was correlated with other traits: species fruiting on living trees, earlier decay stages and deciduous hosts tend to fruit higher above the ground. While our data do…
Lobesia botrana larvae develop faster in the presence of parasitoids.
2013
3 pages; International audience; To combat parasitism hosts often rely on their immune system, which is the last line of defense. However, the immune system may not always be effective, and other non-immunological defenses might be favored to reduce the cost of parasite infection. Here we report that larvae of the moth Lobesia botrana can rapidly accelerate their development and reach maturity earlier in response to cues perceived at a distance from parasitoids. Such a phenotypically plastic life history shift, induced by the perception of deadly enemies in the environment, is likely to be an adaptive defensive strategy to prevent parasitoid attack, and has important implications in host-pa…
Migration strategies of brown trout (Salmo trutta) in a subarctic river system as revealed by stable isotope analysis
2018
We estimated the proportions of anadromous and freshwater‐resident brown trout (Salmo trutta) in different parts of the subarctic River Näätämöjoki/Neidenelva system (Finland and Norway) using carbon, nitrogen and hydrogen stable isotope analyses of archived scales as identifiers of migration strategy. Our results showed that carbon stable isotope values were the best predictor of migration strategy. Most individuals fell into two clearly distinct groups representing anadromous (47%) or freshwater‐resident (42%) individuals, but some fish had intermediate carbon values suggesting repeated movement between freshwater and the sea. The proportion of anadromous individuals decreased steadily wi…
Robert de Montessus de Ballore's 1902 theorem on algebraic continued fractions : genesis and circulation
2013
Robert de Montessus de Ballore proved in 1902 his famous theorem on the convergence of Pad\'e approximants of meromorphic functions. In this paper, we will first describe the genesis of the theorem, then investigate its circulation. A number of letters addressed to Robert de Montessus by different mathematicians will be quoted to help determining the scientific context and the steps that led to the result. In particular, excerpts of the correspondence with Henri Pad\'e in the years 1901-1902 played a leading role. The large number of authors who mentioned the theorem soon after its derivation, for instance N\"orlund and Perron among others, indicates a fast circulation due to factors that w…
Long-term performance and life cycle assessment of energy piles in three different climatic conditions
2020
Abstract The main purpose behind the use of energy piles is to enable the exploitation of geothermal energy for meeting the heating/cooling demands of buildings in an efficient and environment-friendly manner. However, the long-term performance of energy piles in different climatic conditions, along with their actual environmental impacts, has not been fully assessed. In this paper, the results of a finite element model taking into consideration the heating and cooling demands of a reference building, and the intermittent operation of a ground source heat pump, are revealed to examine the long-term performance of energy piles. Furthermore, a life cycle assessment model is implemented to com…
Rodzinna postpamięć Ślązaków
2017
Family Postmemory of the People of Silesia
 The author suggests a possible use of postmemory to analyse the contemporary family memory of the people of Silesia. Their memoirs about WW2 (such as working for the Wehrmacht, the Red Army invading Silesia, working in labour camps, nationality verification, displacements to Germany, and deportations to Siberia) bear signs of latent memory which is rarely revealed even to the next of kin. Present mainly within the family circle, within the local society, and among friends, these memoirs integrated Silesians and made them a unique community that considers itself a stigmatized minority. This contributed to mythologizing and stereotyping the who…
Miracles in Dark Times: Hannah Arendt and Refugees as ‘Vanguard’
2019
AbstractThe radical uncertainty that refugees face because of war, flight and exile often dramatically shapes their participation in society. Violent conflict and human rights abuses are not just disproportionately experienced by, but can also create, political subjects. Such life events can transform the motivations, sense of responsibility and political actions of individuals with refugee backgrounds. In this article, we explore the links between civil–political engagement and the life stories of such individuals, analysing our empirical data through themes in the work of Hannah Arendt. We make three central points. First, we highlight the possibility of refugees as ‘vanguard’, playing a …
The privatization of death: the emergence of private cemeteries in Romania’s postsocialist deathscape
2020
Private cemeteries constitute a new development in the Romanian postsocialist death system that poses a challenge to the traditional burial culture. This paper charts the emergence of privately own...