Ano (214)
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214
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Red-backed Shrikes (Lanius collurio) adjust the mobbing intensity, but not mobbing frequency, by assessing the potential threat to themselves from different predators
NĚMEC, Michal
2013 - anglický
We tested ability to adjust nest defence in the red-backed shrike. We presented dummies of three species of adult bird predators (sparrowhawk, kestrel, and long-eared owl; differing in the potential danger for the defending birds), plus two species of nest predators (jay and magpie; differing in the proportion of nestlings of small passerines in their diets). A dummy pigeon was used as the control. Shrikes regularly attacked all of the dummies tested, with the exception of the magpie and pigeon. We tested ability to adjust nest defence in the red-backed shrike. We presented dummies of three species of adult bird predators (sparrowhawk, kestrel, and long-eared owl; differing in the potential danger for the defending birds), plus two species of nest predators (jay and magpie; differing in the proportion of nestlings of small passerines in their diets). A dummy pigeon was used as the control. Shrikes regularly attacked all of the dummies tested, with the exception of the magpie and pigeon.
Klíčová slova:
mobbing; red-backed shrike; nest defence; antipredator behaviour
Plné texty jsou dostupné v digitálním repozitáři JČU.
Red-backed Shrikes (Lanius collurio) adjust the mobbing intensity, but not mobbing frequency, by assessing the potential threat to themselves from different predators
We tested ability to adjust nest defence in the red-backed shrike. We presented dummies of three species of adult bird predators (sparrowhawk, kestrel, and long-eared owl; differing in the potential ...
The fine-scale utilization of forest edges by mammalian mesopredators related to patch size and conservation issues in Central European farmland
ČERVINKA, Jaroslav
2012 - anglický
In this study we investigated the edge effect in relation to different forest fragment size. We found strong edge preferences for the whole community of autochthonous carnivore species in all fragments regardless the fragment size. Our findings confirm that mammalian mesopredators strongly prefer habitat edges and small forest fragments.
Klíčová slova:
Edge effect; fragment size; mammalian mesopredators; fragmentation; scent stations; Czech Republic
Plné texty jsou dostupné v digitálním repozitáři JČU.
The fine-scale utilization of forest edges by mammalian mesopredators related to patch size and conservation issues in Central European farmland
In this study we investigated the edge effect in relation to different forest fragment size. We found strong edge preferences for the whole community of autochthonous carnivore species in all ...
Vegetation and carbon gas dynamics under a changed hydrological regime in central European peatlands
URBANOVÁ, Zuzana
2012 - anglický
The effect of drainage and restoration on the ecology of different types of peatlands in the Šumava Mountains was investigated. The study was focused primarily vegetation dynamics, carbon gas fluxes and their linkages under the affected hydrological regimes. The effect of drainage and restoration on the ecology of different types of peatlands in the Šumava Mountains was investigated. The study was focused primarily vegetation dynamics, carbon gas fluxes and their linkages under the affected hydrological regimes.
Klíčová slova:
peatland; drainage; restoration; CH4; CO2; carbon; fen; bog
Plné texty jsou dostupné v digitálním repozitáři JČU.
Vegetation and carbon gas dynamics under a changed hydrological regime in central European peatlands
The effect of drainage and restoration on the ecology of different types of peatlands in the Šumava Mountains was investigated. The study was focused primarily vegetation dynamics, carbon gas fluxes ...
Long-Term Cold Acclimation Extends Survival Time at 0°C and Modifies the Metabolomic Profiles of the Larvae of the Fruit Fly Drosophila melanogaster
KORBELOVÁ, Jaroslava
2012 - anglický
Práce vyhodnocuje přežívání larev octomilky Drosophila melanogaster v 0°C po jejich odchovu ve třech různých aklimačních režimech. Porovnání larev aklimovaných v konstantních 25°C s larvami aklimovanými v konstantních 15°C následovaných konstantní teplotou 6°C po 2 dny ukázalo, že dlouhodobá chladová aklimace prodlužuje dobu přežití u 50% populace (Lt50) při vystavení konstantní teplotě 0°C více než 630-krát (z 0,137 hodin na 86,658 hodin). Podrobné metabolomické analýzy prokázaly, že dlouhodobá chladová aklimace mění metabolomický profil larev. Nejvýznamnější odpovědí byla akumulace prolinu (až 17,7 mM) a trehalózy (až 36,5 mM). Také byla pozorována restrukturalizace skladby glycerofosfolipidů biologických membrán. We assessed survival of larvae of the fruit fly, Drosophila melanogaster at 0°C after rearing them under three different acclimation regimes. A comparison of the larvae acclimated at constant 25°C with those acclimated at constant 15°C followed by constant 6°C for 2 d showed that long-term cold acclimation extended the lethal time for 50% of the population (Lt50) during exposure to constant 0°C as much as 630-fold (from 0.137 h to 86.658 h). Detailed metabolomic analyses showed that long-term cold acclimation modified the metabolomic profiles of the larvae. The most prominent responses were accumulations of proline (up to 17.7 mM) and trehalose (up to 36.5 mM). In addition, restructuring of the glycerophospholipid composition of biological membranes was observed.
Klíčová slova:
Drosophila melanogaster; chladová aklimace; přežívání; metabolomické analýzy
Plné texty jsou dostupné v digitálním repozitáři JČU.
Long-Term Cold Acclimation Extends Survival Time at 0°C and Modifies the Metabolomic Profiles of the Larvae of the Fruit Fly Drosophila melanogaster
Práce vyhodnocuje přežívání larev octomilky Drosophila melanogaster v 0°C po jejich odchovu ve třech různých aklimačních režimech. Porovnání larev aklimovaných v konstantních 25°C s larvami ...
Tick sialostatins L and L2 differentially influence dendritic cell responses to Borrelia spirochetes
PÁLENÍKOVÁ, Jana
2015 - anglický
Při přenosu patogenů z klíštěte na hostitele hrají zásadní roli molekuly uvolňované ze slinných žláz během sání. Dendritické buňky působí jako imunitní sentinely, spojují přirozenou a získanou imunitu a kontrolují její vývoj směrem k Th1 či Th2 fenotypu. V práci jsme se zaměřili na vliv cystatinů z Ixodes scapularis, Sialo L a L2 na myší dendritické buňky stimulované boreliemi a TLR ligandy. Transmission of pathogens by ticks is greatly supported by tick saliva released during feeding. Dendritic cells (DC) act as immunological sentinels and interconnect the innate and adaptive immune system. They control polarization of the immune response towards Th1 or Th2 phenotype. We investigated whether salivary cystatins from the hard tick Ixodes scapularis, sialostatin L (Sialo L) and sialostatin L2 (Sialo L2), influence mouse dendritic cells exposed to Borrelia burgdorferi and relevant Toll-like receptor ligands.
Klíčová slova:
dendritické buňky; Borrelia burgdorferi; klíštěcí cystatiny; signalizace
Plné texty jsou dostupné v digitálním repozitáři JČU.
Tick sialostatins L and L2 differentially influence dendritic cell responses to Borrelia spirochetes
Při přenosu patogenů z klíštěte na hostitele hrají zásadní roli molekuly uvolňované ze slinných žláz během sání. Dendritické buňky působí jako imunitní sentinely, spojují přirozenou a získanou imunitu ...
Hidden diversity and evolutionary trends in malacosporean parasites (Cnidaria: Myxozoa) identified using molecular phylogenetics
HRABCOVÁ, Martina
2015 - anglický
Malacosporeans represent only a minor part of the huge myxozoan diversity, accounting for more than 2000 species. In contrast to the remainder of the Myxozoa, malacosporeans cycle between vertebrate (fish) and invertebrate (bryozoans) hosts and are restricted to freshwater habitats. The present study applies light microscopy and molecular methods to scrutinize the morphology, prevalence, diversity, distribution as well as host and habitat preference of malacosporeans in fish hosts. Comprehensive phylogenetic analyses based on newly obtained malacosporean SSU rDNA sequences and those available in GenBank reveal important evolutionary trends in this group. The significant increase in malacosporean species richness unveiled in the present study points to a hidden biodiversity. Reasons for this cryptic species diversity, the potential existence of malacosporean life cycles in marine environment as well as the evolution of worm- and sac-like morphology in bryozoan host are discussed.
Plné texty jsou dostupné v digitálním repozitáři JČU.
Hidden diversity and evolutionary trends in malacosporean parasites (Cnidaria: Myxozoa) identified using molecular phylogenetics
Malacosporeans represent only a minor part of the huge myxozoan diversity, accounting for more than 2000 species. In contrast to the remainder of the Myxozoa, malacosporeans cycle between vertebrate ...
Improved demethylation in ecological epigenetic experiments: Testing a simple and harmless foliar demethylation application
DVOŘÁKOVÁ, Hana
2019 - anglický
Spray application of 5azacytidine on established plant seedlings was tested for its demethylating efficiency. It represents a novel method for plant experimental demethylation with a potentially lower negative impact on plant development compared to the traditional application of the demethylating agent through germination of seeds in its solution. Further, the 5azacytidine spray application was used in practice to erase the epigenetic memory in offspring of Taraxacum brevicorniculatum plants from different competitive conditions. The impact of parental competition on the juvenile phenotype was estimated by measuring growth related traits, while the experimental demethylation allowed for evaluating the significance of DNA methylation marks in bioticaly induced transgenerational effects in T. brevirorniculatum. Spray application of 5azacytidine on established plant seedlings was tested for its demethylating efficiency. It represents a novel method for plant experimental demethylation with a potentially lower negative impact on plant development compared to the traditional application of the demethylating agent through germination of seeds in its solution. Further, the 5azacytidine spray application was used in practice to erase the epigenetic memory in offspring of Taraxacum brevicorniculatum plants from different competitive conditions. The impact of parental competition on the juvenile phenotype was estimated by measuring growth related traits, while the experimental demethylation allowed for evaluating the significance of DNA methylation marks in bioticaly induced transgenerational effects in T. brevirorniculatum.
Klíčová slova:
5-azacytidine; competition; demethylation; DNA methylation; ecological epigenetics; ecology; plant memory; plant performance; toxicity; transgenerational effects
Plné texty jsou dostupné v digitálním repozitáři JČU.
Improved demethylation in ecological epigenetic experiments: Testing a simple and harmless foliar demethylation application
Spray application of 5azacytidine on established plant seedlings was tested for its demethylating efficiency. It represents a novel method for plant experimental demethylation with a potentially lower ...
Distribution of herbivorous fish is frozen by low temperature
VEJŘÍKOVÁ, Ivana
2019 - anglický
The number of herbivores in populations of ectothermic vertebrates decreases with increasing latitude. At higher latitudes, fish consuming plant matter are exclusively omnivorous. We assess whether omnivorous fish readily shift to herbivory or whether animal prey is typically preferred. We address temperature as the key factor causing their absence at higher latitudes and discuss the potential poleward dispersion caused by climate changes. A controlled experiment illustrates that rudd (Scardinius erythrophthalmus) readily utilize plant matter at water temperatures above 20 °C and avoid its consumption below 20 °C. Field data support these results, showing that plant matter dominates rudd diets during the summer and is absent during the spring. Utilizing cellulose requires the enzyme cellulase, which is produced by microorganisms growing at temperatures of 15-42 °C. Water temperatures at higher latitudes do not reach 15 °C year-round; at our latitude of 50°N~150 days/year. Hence, the species richness of omnivorous fish decreases dramatically above 55° latitude. Our results provide support for the hypothesis that strict herbivorous specialists have developed only in the tropics. Temperatures below 15 °C, even for a short time period, inactivate cellulase and cause diet limitations for omnivorous fish. However, we may expect increases in herbivory at higher latitudes caused by climate change. The number of herbivores in populations of ectothermic vertebrates decreases with increasing latitude. At higher latitudes, fish consuming plant matter are exclusively omnivorous. We assess whether omnivorous fish readily shift to herbivory or whether animal prey is typically preferred. We address temperature as the key factor causing their absence at higher latitudes and discuss the potential poleward dispersion caused by climate changes. A controlled experiment illustrates that rudd (Scardinius erythrophthalmus) readily utilize plant matter at water temperatures above 20 °C and avoid its consumption below 20 °C. Field data support these results, showing that plant matter dominates rudd diets during the summer and is absent during the spring. Utilizing cellulose requires the enzyme cellulase, which is produced by microorganisms growing at temperatures of 15-42 °C. Water temperatures at higher latitudes do not reach 15 °C year-round; at our latitude of 50°N~150 days/year. Hence, the species richness of omnivorous fish decreases dramatically above 55° latitude. Our results provide support for the hypothesis that strict herbivorous specialists have developed only in the tropics. Temperatures below 15 °C, even for a short time period, inactivate cellulase and cause diet limitations for omnivorous fish. However, we may expect increases in herbivory at higher latitudes caused by climate change.
Klíčová slova:
cellulase; climate change; latitudinal gradient; macrophytes; Scardinius erythrophthalmus; temperature pattern
Plné texty jsou dostupné v digitálním repozitáři JČU.
Distribution of herbivorous fish is frozen by low temperature
The number of herbivores in populations of ectothermic vertebrates decreases with increasing latitude. At higher latitudes, fish consuming plant matter are exclusively omnivorous. We assess whether ...
Association between louse abundance and MHC II supertypes in Galápagos mockingbirds
VLČEK, Jakub
2022 - anglický
In this thesis I describe association between abundance of ectoparasitic lice and supertypes of major histocompatibility complex in mockingbirds of Galápagos islands. I report a significant association between several supertypes and the lice abundance. Lice abundance was correlated also with heterocyte to lymphocyte ratio, an immunogenetic index reflecting rate of immune stress. This scientific contribution is valuable, because ectoparasite abundance in birds was rarely contrasted to MHC and other immune indices. In this thesis I describe association between abundance of ectoparasitic lice and supertypes of major histocompatibility complex in mockingbirds of Galápagos islands. I report a significant association between several supertypes and the lice abundance. Lice abundance was correlated also with heterocyte to lymphocyte ratio, an immunogenetic index reflecting rate of immune stress. This scientific contribution is valuable, because ectoparasite abundance in birds was rarely contrasted to MHC and other immune indices.
Klíčová slova:
ectoparasite; immunity; genes; major histocompatibility complex
Plné texty jsou dostupné v digitálním repozitáři JČU.
Association between louse abundance and MHC II supertypes in Galápagos mockingbirds
In this thesis I describe association between abundance of ectoparasitic lice and supertypes of major histocompatibility complex in mockingbirds of Galápagos islands. I report a significant ...
World travellers: phylogeny and biogeography of the butterfly genus Leptotes (Lepidoptera: Lycaenidae)
PAPP MAREŠOVÁ, Jana
2019 - anglický
V této práci jsme se zabývali fylogenetickými a biogeografickými vztahy opomíjených motýlů subtribu Leptotina (Lepidoptera: Lycaenidae), který je široce rozšířen v tropických a subtropických oblastech celého světa. Použili jsme jak mitochondriální tak nukleární markery a různé molekulární analýzy, abychom odhalili vztahy v rámci tohoto subtribu. Také jsme se zaměřili na časy diverzifikace a biogeografické patrnosti taxonů Starého světa a zabývali jsme se detailní fylogeografií nejrozšířenějšího druhu, Leptotes pirithous. In this thesis, we investigated phylogenetic and biogeographical relationships of neglected butterflies of the subtribe Leptotina (Lepidoptera: Lycaenidae), widely distributed in tropical and subtropical areas around the world. We used both mitochondrial and nuclear markers and different molecular analyses to resolve relationships within the subtribe. We also focused on diversification times and biogeographical patterns of Old World taxa and detailed phylogeography of the most widespread species, Leptotes pirithous.
Klíčová slova:
biogeografie; COI; Cyclyrius; Ef1a; Leptotina; fylogeneze; wingless
Plné texty jsou dostupné v digitálním repozitáři JČU.
World travellers: phylogeny and biogeography of the butterfly genus Leptotes (Lepidoptera: Lycaenidae)
V této práci jsme se zabývali fylogenetickými a biogeografickými vztahy opomíjených motýlů subtribu Leptotina (Lepidoptera: Lycaenidae), který je široce rozšířen v tropických a subtropických oblastech ...
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