Search results for "Alis"

An alien fish threatens an endangered parasitic bivalve: the relationship between brook trout (Salvelinus fontinalis) and freshwater pearl mussel (Ma…

2016

Host–parasite interactions may play a significant role in biological invasions: for example, an invader may benefit from lower infectivity by native parasites in competition against the native hosts (‘enemy release hypothesis’). The invasive North American brook trout (Salvelinus fontinalis) is replacing the native salmonid hosts of the freshwater pearl mussel (FPM, Margaritifera margaritifera) in northern Europe, but the suitability of brook trout as a host for FPM is poorly known. In this study its suitability was investigated using an array of laboratory and field experiments, and several FPM populations from a catchment in northern Finland. The occurrence of brook trout in FPM rivers in…

2018

Odonate (damselfly and dragonfly) species richness and species occupancy frequency distributions (SOFDs) were analyzed in relation to geographical location in standing waters (lakes and ponds) in Fennoscandia, from southern Sweden to central Finland. In total, 46 dragonfly and damselfly species were recorded from 292 waterbodies. Species richness decreased to the north and increased with waterbody area in central Finland, but not in southern Finland or in Sweden. Species occupancy ranged from 1 up to 209 lakes and ponds. Over 50% of the species occurred in <10% of the waterbodies, although this proportion decreased to the north. In the southern lakes and ponds, none of the species occurred …

Electrotechnologies applied to valorization of by-products from food industry: Main findings, energy and economic cost of their industrialization

2016

Abstract There has been a growing interest to reuse food waste and by-products from different processing steps, not only to ensure the environmental sustainability but also to improve the economic performance of the processes. One way of recovery that has raised more interest is the extraction of valuable compounds, which can be used as ingredients in food and pharmaceutical industries due to their technological function, nutritional properties, or their beneficial effects on human or animal health. In many cases, conventional solvent extraction cannot be economically feasible or involves the use of toxic solvents, hindering their subsequent management, or high temperatures, with consequent…

Gray plumage color is more cryptic than brown in snowy landscapes in a resident color polymorphic bird

2020

Abstract Camouflage may promote fitness of given phenotypes in different environments. The tawny owl (Strix aluco) is a color polymorphic species with a gray and brown morph resident in the Western Palearctic. A strong selection pressure against the brown morph during snowy and cold winters has been documented earlier, but the selection mechanisms remain unresolved. Here, we hypothesize that selection favors the gray morph because it is better camouflaged against predators and mobbers in snowy conditions compared to the brown one. We conducted an online citizen science experiment where volunteers were asked to locate a gray or a brown tawny owl specimen from pictures taken in snowy and snow…

Ectosymbiosis is a critical factor in the local benthic biodiversity of the Antarctic deep sea.

2008

10 pages; International audience; In deep-sea benthic environments, competition for hard substrates is a critical factor in the distribution and diversity of organisms. In this context, the occurrence of biotic substrates in addition to mineral substrates may change the characteristics of sessile fauna. We tested this hypothesis at different localities of the Weddell Sea (Antarctica) by studying the diversity of ectosymbionts living on the spines of cidaroids (echinoids). The presence of cidaroids promoted a higher total specific richness and increased sessile species abundance, but did not change the diversity. Analyses of species distribution suggested that the cidaroids are a favourable …

Voles and weasels in the boreal Fennoscandian small mammal community : What happens if the least weasel disappears due to climate change?

2019

Climate change, habitat loss and fragmentation are major threats for populations and a challenge for individual behavior, interactions and survival. Predator–prey interactions are modified by climate processes. In the northern latitudes, strong seasonality is changing and the main predicted feature is shortening and instability of winter. Vole populations in the boreal Fennoscandia exhibit multiannual cycles. High amplitude peak numbers of voles and dramatic population lows alternate in 3–5‐year cycles shortening from North to South. One key factor, or driver, promoting the population crash and causing extreme extended lows, is suggested to be predation by the least weasel. We review the ar…

FOOD MAKES YOU A TARGET: DISENTANGLING GENETIC, PHYSIOLOGICAL, AND BEHAVIORAL EFFECTS DETERMINING SUSCEPTIBILITY TO INFECTION

2010

Genetics, physiology, and behavior are all expected to influence the susceptibility of hosts to parasites. Furthermore, interactions between genetic and other factors are suggested to contribute to the maintenance of genetic polymorphism in resistance when the relative susceptibility of host genotypes is context dependent. We used a maternal sibship design and long- and short-term food deprivation treatments to test the role of family-level genetic variation, body condition, physiological state, and foraging behavior on the susceptibility of Lymnaea stagnalis snails to infection by a trematode parasite that uses chemical cues to locate its hosts. In experimental exposures, we found that sna…

The roles of foraging environment, host species, and host diet for a generalist pupal parasitoid

2018

Ultrastructural and cell wall modifications during infection of Eucalyptus viminalis roots by a pathogenic Fusarium oxysporum strain

2004

Fusarium species are soil-borne fungal pathogens that produce a variety of disease symptoms when attacking crop plants. The mode of root colonization of Eucalyptus viminalis seedlings by a pathogenic F. oxyporum strain (Foeu1) at the ultrastructural level and changes in cell wall pectin during host pathogen interactions are described. Root systems of E. viminalis plants were inoculated with F. oxysporum in an in vitro model system. Hyphae of F. oxysporum adhered to the outer epidermal cell walls through fibrillar material, and after penetration they spread into the internal tissues. They developed intercellularly and intracellularly in the root cortex and invaded vascular tissues. Papillae …

Genetic variation in the mechanisms of direct mutual interference in a parasitic wasp: consequences in terms of patch-time allocation

2004

Summary 1. Direct mutual interference between insect parasitoids has always been considered to have major consequences for the population dynamics of parasitoid‐host systems. Furthermore, patch time allocation has also always been presented as an important behavioural component that is closely involved in the demographic features of host‐ parasitoid interactions. 2. Based on a detailed analysis of within-patch interactions between Trissolcus basalis (Hymenoptera: Scelionidae) females, the present study aimed to understand accurately how direct mutual interference can influence patch time allocation in this species. 3. The genetic variation in the behavioural mechanisms involved in the inter…