Search results for "evolutionary"
showing 10 items of 4392 documents
Potential Solar Radiation as a Driver for Bark Beetle Infestation on a Landscape Scale
2019
In recent decades, Norway spruce (Picea abies L. Karst.) forests of the High Tatra Mountains have suffered unprecedented tree mortality caused by European spruce bark beetle (Ips typographus L.). Analysis of the spatiotemporal pattern of bark beetle outbreaks across the landscape in consecutive years can provide new insights into the population dynamics of tree-killing insects. A bark beetle outbreak occurred in the High Tatra Mountains after a storm damaged more than 10,000 ha of forests in 2004. We combined yearly Landsat-derived bark beetle infestation spots from 2006 to 2014 and meteorological data to identify the susceptibility of forest stands to beetle infestation. We found that digi…
New data about Chiropterofauna of the “Monte Pellegrino” Nature Reserve (Palermo, Italy)
2021
This work increase the knowledge related to bat fauna present in the “Monte Pellegrino” Nature Reserve in the Palermo municipality. The acoustic sampling took place in the summer/autumn season using the D500X Bat detector in 22 samples. The identified signals were attributed to 8 species and one genus. The Taxa with the most passes in the reserve are: Tadarita teniotis followed by Pipistrellus kuhlii, Hypsugo savii (100% of Costancy), Pipistrellus pygmaeus, Pipistrellus pipistrellus, Plecotus sp., Miniopterus schreibersii and last with a single recording Rhinolophus ferrumequinum and Rhinolophus hipposideros. The dendrogram of similarity shows 3 distinct bats cenosis. Two samples present in…
Traits mediate niches and co‐occurrences of forest beetles in ways that differ among bioclimatic regions
2021
Aim The aim of this study was to investigate the role of traits in beetle community assembly and test for consistency in these effects among several bioclimatic regions. We asked (1) whether traits predicted species’ responses to environmental gradients (i.e. their niches), (2) whether these same traits could predict co-occurrence patterns and (3) how consistent were niches and the role of traits among study regions. Location Boreal forests in Norway and Finland, temperate forests in Germany. Taxon Wood-living (saproxylic) beetles. Methods We compiled capture records of 468 wood-living beetle species from the three regions, along with nine morphological and ecological species traits. Eight …
The Bias of combining variables on fish's aggressive behavior studies.
2019
Made available in DSpace on 2019-10-06T16:27:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-07-01 Quantifying animal aggressive behavior by behavioral units, either displays or attacks, is a common practice in animal behavior studies. However, this practice can generate a bias in data analysis, especially when the variables have different temporal patterns. This study aims to use Bayesian Hierarchical Linear Models (B-HLMs) to analyze the feasibility of pooling the aggressive behavior variables of four cichlids species. Additionally, this paper discusses the feasibility of combining variables by examining the usage of different sample sizes and family distributions to aggressive …
Modelling prey-predator interactions in Messina beachrock pools
2020
Abstract The Strait of Messina (Sicily, Italy) attracts the interest of marine ecologists for the presence of a large variety of habitat and mutually-interacting communities. Among them, beachrock formations, despite their wide geographic distribution, which also includes the Mediterranean area, have been poorly investigated from the biotic viewpoint. In this paper, the spatial and seasonal variability of benthic megafauna from the Messina microtidal beachrock is described. Combining in situ collected data (measurements of abiotic parameters and underwater visual census) with theoretical post-processing analyses (analysis of similarity percentages and cluster analysis), we deduced the possi…
Octopamine and dopamine mediate waggle dance following and information use in honeybees.
2020
Honeybees can be directed to profitable food sources by following waggle dances performed by other bees. Followers can often choose between using this social information or relying on memories about food sources they have visited in the past, so-called private information. While the circumstances that favour the use of either social or private information have received considerable attention, still little is known about the neurophysiological basis of information use. We hypothesized that octopamine and dopamine, two biogenic amines with important functions in reward signalling and learning, affect dance use in honeybees. We orally administered octopamine and dopamine when bees collected fo…
The effects of parasite age and intensity on variability in acanthocephalan-induced behavioural manipulation.
2008
10 pages; International audience; Numerous parasites with complex life cycles are able to manipulate the behaviour of their intermediate host in a way that increases their trophic transmission to the definitive host. Pomphorhynchus laevis, an acanthocephalan parasite, is known to reverse the phototactic behaviour of its amphipod intermediate host, Gammarus pulex, leading to an increased predation by fish hosts. However, levels of behavioural manipulation exhibited by naturally-infected gammarids are extremely variable, with some individuals being strongly manipulated whilst others are almost not affected by infection. To investigate parasite age and parasite intensity as potential sources o…
Eye fluke-induced cataracts in natural fish populations: is there potential for host manipulation?
2010
SUMMARYManipulation of host phenotype (e.g. behaviour, appearance) is suggested to be a common strategy to enhance transmission in trophically transmitted parasites. However, in many systems, evidence of manipulation comes exclusively from laboratory studies and its occurrence in natural host populations is poorly understood. Here, we examined the potential for host manipulation by Diplostomum eye flukes indirectly by quantifying the physiological effects of parasites on fish. Earlier laboratory studies have shown that Diplostomum infection predisposes fish to predation by birds (definitive hosts of the parasites) by reducing fish vision through cataract formation. However, occurrence of ca…
Red Listing plants under full national responsibility: Extinction risk and threats in the vascular flora endemic to Italy
2018
Abstract Taxa endemic to a country are key elements for setting national conservation priorities and for driving conservation strategies, since their persistence is entirely dependent on national policy. We applied the IUCN Red List categories to all Italian endemic vascular plants (1340 taxa) to assess their current risk of extinction and to highlight their major threats. Our results revealed that six taxa are already extinct and that 22.4% (300 taxa) are threatened with extinction, while 18.4% (247; especially belonging to apomictic groups) have been categorized as Data Deficient. Italian endemic vascular plants are primarily threatened by natural habitat modification due to agriculture, …
Conserving plant diversity in Europe: outcomes, criticisms and perspectives of the Habitats Directive application in Italy
2016
Habitat Directive is the core strategy of nature conservation in Europe aiming at halting biodiversity loss. In this study the results of the third Italian assessment regarding the conservation status (CS) of plants listed in the Habitat Directive (Flora of community interest—FCI) was presented. Data was collected from several sources related to plant distribution, population data, habitats and pressures. Following the official European procedure, all parameters were evaluated and combined to give the CS of each taxon in each biogeographical region of presence. A comparison between the recent Italian IUCN and Reporting assessments was performed in order to evaluate the consistency between t…