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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 ...
Tasty rewards for ants: differences in elaiosome and seed metabolite profiles are consistent across species and reflect taxonomic relatedness
KONEČNÁ, Marie
2023 - anglický
The reward for ants in myrmecochory is a nutrient-rich appendage, the elaiosome. This study evaluates the metabolite composition of five groups (i.e. amino acids, fatty acids, organic acids, polyols, and sugars) in elaiosomes compared to the respective seeds. Two plant species from each of the four families (Amaryllidaceae, Boraginaceae, Papaveraceae, and Poaceae) were examined, with each species represented by three populations. The hierarchically designed data enabled the decomposition of variability in metabolite composition at three levels: family, species, and population. Another aspect studied was the consistency of elaiosome metabolite composition across unrelated species from monocotyledonous and dicotyledonous families with different elaiosome origins, which may reflect the convergent evolution of elaiosomes. The reward for ants in myrmecochory is a nutrient-rich appendage, the elaiosome. This study evaluates the metabolite composition of five groups (i.e. amino acids, fatty acids, organic acids, polyols, and sugars) in elaiosomes compared to the respective seeds. Two plant species from each of the four families (Amaryllidaceae, Boraginaceae, Papaveraceae, and Poaceae) were examined, with each species represented by three populations. The hierarchically designed data enabled the decomposition of variability in metabolite composition at three levels: family, species, and population. Another aspect studied was the consistency of elaiosome metabolite composition across unrelated species from monocotyledonous and dicotyledonous families with different elaiosome origins, which may reflect the convergent evolution of elaiosomes.
Klíčová slova:
Myrmecochory; Convergent evolution; Variation partitioning; Ant-plant mutualism; Seed dispersal
Plné texty jsou dostupné v digitálním repozitáři JČU.
Tasty rewards for ants: differences in elaiosome and seed metabolite profiles are consistent across species and reflect taxonomic relatedness
The reward for ants in myrmecochory is a nutrient-rich appendage, the elaiosome. This study evaluates the metabolite composition of five groups (i.e. amino acids, fatty acids, organic acids, polyols, ...
The Effect of P Enrichment on Exudate Quantity and Bioavailability - a Comparison of Two Macrophyte Species
KUBEŠOVÁ, Jaroslava
2016 - anglický
A study on rhizodeposition rates and rhizodeposits bioavailability (microbial respiration, N mineralization and phosphatase activity) of two macrophyte species with different life strategies (stress-tolerator and competitor) was conducted. Research was carried out in tropical marshes of Belize; results from the field were supported by 13C partitioning mesocosm study. The stresstolerant Eleocharis spp. released more C from roots than Typha domingensis and this C was more biodegradable. The two species responded to P enrichment differently. While Eleocharisspp. invested more assimilated C to the belowground (roots, rhizomes and rhizodepositions) after P fertilization, in T. domingensis the belowground C investment decreased. The effect of plant species was larger than the effect of P enrichment. Eleocharis spp., adapted to growth under low nutrients, invests more carbon into exudation a promotion of its microbial communities in the rhizosphere while competitive T. domingensis spends more fixed C on its own growth and metabolism.
Klíčová slova:
Biological availability; C partitioning; Eutrophication; Herbaceous marshes; Mineralization; P limitation; Plant life strategy; Rhizodeposition/Exudation
Plné texty jsou dostupné v digitálním repozitáři JČU.
The Effect of P Enrichment on Exudate Quantity and Bioavailability - a Comparison of Two Macrophyte Species
A study on rhizodeposition rates and rhizodeposits bioavailability (microbial respiration, N mineralization and phosphatase activity) of two macrophyte species with different life strategies ...
A peek into diversity of terrestrial cyanobacteria collected in San Gerardo de Rivas region, Costa Rica.
HAUEROVÁ, Radka
2017 - anglický
The presented thesis focuses on diversity of cyanobacteria collected from terrestrial habitats in the surroundings of San Gerardo de Rivas, Costa Rica. The first part of this thesis consists of a floristic survey performed on dried and subsequently revived samples using light microscopy. The second part introduces new cyanobacterial genus Calochaete (Microchaetaceae, Nostocales) with the type species C. cimrmanii. The presented thesis focuses on diversity of cyanobacteria collected from terrestrial habitats in the surroundings of San Gerardo de Rivas, Costa Rica. The first part of this thesis consists of a floristic survey performed on dried and subsequently revived samples using light microscopy. The second part introduces new cyanobacterial genus Calochaete (Microchaetaceae, Nostocales) with the type species C. cimrmanii.
Klíčová slova:
cyanobacteria; Costa Rica; biodiversity; floristic survey
Plné texty jsou dostupné v digitálním repozitáři JČU.
A peek into diversity of terrestrial cyanobacteria collected in San Gerardo de Rivas region, Costa Rica.
The presented thesis focuses on diversity of cyanobacteria collected from terrestrial habitats in the surroundings of San Gerardo de Rivas, Costa Rica. The first part of this thesis consists of a ...
Eggs as a Suitable Tool for Species Diagnosis of Causative Agents of Human Diphyllobothriosis (Cestoda)
LEŠTINOVÁ, Kateřina
2016 - anglický
More than 2,000 eggs of 8 species of diphyllobothriid cestodes infecting humans were compared. Combination of morphometrical and ultrastructural (surface morphology) data made it possible to distinguish all species. More than 2,000 eggs of 8 species of diphyllobothriid cestodes infecting humans were compared. Combination of morphometrical and ultrastructural (surface morphology) data made it possible to distinguish all species.
Klíčová slova:
Cestoda; Tapeworms; Diphyllobothrium; eggs; SEM; Human Diphyllobothriosis; ultrastrucure; morphometry
Plné texty jsou dostupné v digitálním repozitáři JČU.
Eggs as a Suitable Tool for Species Diagnosis of Causative Agents of Human Diphyllobothriosis (Cestoda)
More than 2,000 eggs of 8 species of diphyllobothriid cestodes infecting humans were compared. Combination of morphometrical and ultrastructural (surface morphology) data made it possible to ...
How universal are reserve design rules? A test using butterflies and their life history traits
BARTOŇOVÁ, Alena
2017 - anglický
Tato práce testuje platnost ustanovených "reserve design" pravidel - způsobů, jakými jsou plánovány přírodní rezervace. Použili jsme seznamy druhů denních motýlů pro 125 českých Národních přírodních rezervací a Národních přírodních památek. Analýza funkčních vlastností druhů pomocí multivariátní statistiky odhalila odezvu motýlích společenstev na různé geometrické charakteristiky rezervací a jejich heterogenitu. Práce ukazuje, že různé druhy motýlů vyžadují různé vlastnosti rezervací v závislosti na druhových funkčních vlastnostech. This thesis uses butterfly species lists for 125 Czech National Nature Reserves and Monuments to test the validity of generally agreed 'reserve design rules' using multivariate ordination analyses. We used analyses of butterfly life history traits to seek for biological mechanisms responsible for butterfly community responses to geometric and heterogeneity characteristics of the reserves. We found that different design characteristics are important for individual species, depending on their life histories.
Klíčová slova:
motýli; ochrana přírody; rezervace; funkční vlastnosti; heterogenita krajiny
Plné texty jsou dostupné v digitálním repozitáři JČU.
How universal are reserve design rules? A test using butterflies and their life history traits
Tato práce testuje platnost ustanovených "reserve design" pravidel - způsobů, jakými jsou plánovány přírodní rezervace. Použili jsme seznamy druhů denních motýlů pro 125 českých Národních přírodních ...
Legionella Becoming a Mutualist: Adaptive Processes Shaping the Genome of Symbiont in the Louse Polyplax serrata
ŘÍHOVÁ, Jana
2017 - anglický
Genomic modifications coupled with the first known transition of a Legionella bacterium to symbiosis with insects (louse Polyplax serrata). Apart from characteristics typical for other obligatory symbionts in insect (genome reduction), the main innovation of the genome consists in horizontal acquisition of complete biotin operon. Comparative genomic analysis with free living legionellae and other symbiotic bacteria demonstrates convergent evolution of several phylogenetically unrelated louse symbionts.
Klíčová slova:
endosymbiont; Legionella polyplacis; Polyplax serrata; horizontal gene transfer; genome evolution; metabolism
Plné texty jsou dostupné v digitálním repozitáři JČU.
Legionella Becoming a Mutualist: Adaptive Processes Shaping the Genome of Symbiont in the Louse Polyplax serrata
Genomic modifications coupled with the first known transition of a Legionella bacterium to symbiosis with insects (louse Polyplax serrata). Apart from characteristics typical for other obligatory ...
Klíčové faktory složení společenstva sinic dostřikové zóny na dvou chorvatských ostrovech
VONDRÁŠKOVÁ, Alžběta
2018 - anglický
On two Croatian islands, Veruda and Ugljan, cyanobacterial communities and their composition were surveyed. The cyanobacterial composition in the splash zone was examined in horizontal and vertical directions. Statistical analysis shows the vertical gradient as the strongest one on the contrary the horizontal distribution does not reflect any pronounced differences between the islands. The species diversity and distribution is not dependent on the orientation of the locality toward the cardinal points. The study highlights the importance of high-density sampling in the vertical and also the horizontal direction for covering sufficiently the species richness of the site.
Klíčová slova:
biofilm; Croatian coast; endolithic; epilithic; marine shore; zonation
Plné texty jsou dostupné v digitálním repozitáři JČU.
Klíčové faktory složení společenstva sinic dostřikové zóny na dvou chorvatských ostrovech
On two Croatian islands, Veruda and Ugljan, cyanobacterial communities and their composition were surveyed. The cyanobacterial composition in the splash zone was examined in horizontal and vertical ...
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