Search results for "lag"
showing 10 items of 3124 documents
Getting there and around: Host range oscillations during colonization of the Canary Islands by the parasitic nematode Spauligodon
2016
Episodes of expansion and isolation in geographic range over space and time, during which parasites have the opportunity to expand their host range, are linked to the development of host-parasite mosaic assemblages and parasite diversification. In this study, we investigated whether island colonization events lead to host range oscillations in a taxon of host-specific parasitic nematodes of the genus Spauligodon in the Canary Islands. We further investigated whether range oscillations also resulted in shifts in host breadth (i.e., specialization), as expected for parasites on islands. Parasite phylogeny and divergence time estimates were inferred from molecular data with Bayesian methods. H…
Through predators’ eyes: phenotype–environment associations in shore crab coloration at different spatial scales
2017
We thank Emil Aaltonen Foundation providing a young scientist grant for this research (O.N.). MS and AEL were supported by a Biotechnology and Biological Sciences Research Council (BBSRC) David Phillips Research Fellowship (BB/G022887/1).
Spoilage potential of Brettanomyces bruxellensis strains isolated from Italian wines
2018
Abstract Brettanomyces bruxellensis is an important wine spoilage agent. In this study a population of Brettanomyces strains isolated from Italian wines was thoroughly investigated to evaluate adaptability to wine conditions and spoilage potential. The presumptive isolates of Brettanomyces were identified at species level with 26S rRNA gene sequencing and species-specific PCR, and subsequently subjected to analysis of intra-species variability through the study of intron splice sites (ISS-PCR). Although, some strains were tracked in wines from different regions, extensive genetic biodiversity was observed within the B. bruxellensis population investigated. All strains were evaluated for the…
Variable crab camouflage patterns defeat search image formation.
2021
Understanding what maintains the broad spectrum of variation in animal phenotypes and how this influences survival is a key question in biology. Frequency dependent selection – where predators temporarily focus on one morph at the expense of others by forming a “search image” – can help explain this phenomenon. However, past work has never tested real prey colour patterns, and rarely considered the role of different types of camouflage. Using a novel citizen science computer experiment that presented crab “prey” to humans against natural backgrounds in specific sequences, we were able to test a range of key hypotheses concerning the interactions between predator learning, camouflage and mor…
Gastrointestinal parasites of two populations of Arctic foxes (Vulpes lagopus) from north-east Greenland
2017
Parasitological examination of 275 faecal samples from Arctic foxes (Vulpes lagopus) collected at Zackenberg Valley and Karupelv Valley in north-east Greenland from 2006 to 2008 was conducted using sieving and microscopy. Overall, 125 (45.5%) samples contained parasite eggs of Taenia crassiceps, Taenia serialis, Toxascaris leonina, Eucoleus boehmi, Physalopteridae and Ancylostomatidae, and Strongyloides-like larvae. As long-term ecological studies are conducted at both sampling locations, the present findings constitute a baseline data set for further parasitological monitoring.
Selection of Lactobacillus strains to induce biological acidification in low acidity wines
2016
Abstract Because of global warming, wines are obtained nowadays with high pH values and low acidity. This results in wines with disturbed flavor and increased susceptibility of microbial spoilage. The aim of this work was the selection of Lactobacillus strains with ability to induce biological acidification in low acidity grape musts to obtain more acidic wines. A screening of Lactobacillus strains was carried out using several selection criteria. Lactobacillus strains that grew in must, carried out the malolactic fermentation, acidified grape must, synthesized lactic acid from sugars, and showed high resistance to lysozyme and sulfur dioxide were selected. Selected strains were characteriz…
In vitro antifungal activity of bioactive peptides produced by Lactobacillus plantarum against Aspergillus parasiticus and Penicillium expansum
2017
Abstract Food spoilage caused by mycotoxigenic moulds represents an important problem in food security. The antimicrobial peptides are compounds of natural origin constituted by a variable number (5–100) of amino acids held together through peptide bonds. In this work, the cell free supernatants (CFSs) containing peptides obtained from four strains of LAB were lyophilized, filtered and tested to determine the antifungal activity against Aspergillus Parasiticus and Penicillium expansum . CFS obtained by Lactobacillus plantarum showed the highest inhibition activity. CFS was fractionated by size exclusion chromatography and injected into the liquid chromatography coupled to diode array detect…
mtDNA diversity in rabbit population from Sicily (Italy)
2017
The European rabbit Oryctolagus cuniculus (O.c) lives all over the world and it represents an important resource for many predators. It has been classified as a Near-Threatened species in the Red List of Vertebrates of Italy. It is present in mediterranean basin as two known subspecies: O.c. cuniculus and O.c. algirus. The mediterranean geographic distribution of the two subspecies is still not well known. In particular, in Sicily, lacking of deep studies, is based on the body size and morphological characteristics; there wasn’t a complete description of the actual existing subspecies and previous studies only reported the morphological characteristics of the sicilian rabbit population. In …
The current and future state of animal coloration research
2017
Animal colour patterns are a model system for understanding evolution because they are unusually accessible for study and experimental manipulation. This is possible because their functions are readily identifiable. In this final paper of the symposium we provide a diagram of the processes affecting colour patterns and use this to summarize their functions and put the other papers in a broad context. This allows us to identify significant ‘holes’ in the field that only become obvious when we see the processes affecting colour patterns, and their interactions, as a whole. We make suggestions about new directions of research that will enhance our understanding of both the evolution of colour …
Can we rely on selected genetic markers for population identification? Evidence from coastal Atlantic cod
2018
Abstract The use of genetic markers under putative selection in population studies carries the potential for erroneous identification of populations and misassignment of individuals to population of origin. Selected markers are nevertheless attractive, especially in marine organisms that are characterized by weak population structure at neutral loci. Highly fecund species may tolerate the cost of strong selective mortality during early life stages, potentially leading to a shift in offspring genotypes away from the parental proportions. In Atlantic cod, recent genetic studies have uncovered different genotype clusters apparently representing phenotypically cryptic populations that coexist i…