National Repository of Grey Literature 75 records found  beginprevious58 - 67next  jump to record: Search took 0.01 seconds. 
Bird diversity and diversification: Different processes converging to the same pattern?
Černá, Vladimíra ; Storch, David (advisor) ; Hulva, Pavel (referee)
Latitudinal diversity gradient is one of the oldest known trends in the distribution of life on the Earth. Scientists have been trying to find causes of its formation for more than two hundred years. There are several hypotheses suggested to explain this gradient. Recently, it is one of the main themes of discussion among ecologists and evolutionary biologists. By this Thesis, I will try to contribute to understanding of processes that generate the latitudinal diversity gradient. Particularly, I study if there is a relationship between ambient temperature and diversification rate. Is this relationship different for individual groups of animals? I choose birds as a model group. Specifically, these six families of birds: Accipitridae, Columbidae, Furnariidae, Picidae, Psittacidae and Strigidae. These groups include more than 1500 species. Each of them has the same universal gradient of diversity, with the highest diversity concentrated in the tropics. My objective was to find out, whether the universal gradients of bird's diversity had been shaped by the same historical processes. Or alternatively, whether different evolutionary trajectories had converged to the same gradients. The main outcome of my work is a discovery that some of the selected families diversified faster in warmer climates...
Evolutionary history of hedgehogs from genus>Erinaceus
Černá Bolfíková, Barbora ; Hulva, Pavel (advisor) ; Janko, Karel (referee) ; Kryštufek, Boris (referee)
Hedgehogs from the genus Erinaceus are extremely interesting and suitable model organisms for studying impacts of climatic changes during Pleistocene on species and speciation processes. Erinaceus europaeus and E. roumanicus, which have diverged in southern refugia, formed a secondary contact zone in Central Europe. The widest part of this zone is situated in Czech Republic. Our work benefits from this position and processes that take place here such as reinforcement, character displacement and hybridization are discussed. Moreover, we addressed several questions about biological invasions and topics connected to peripatric processes. Using combination of nuclear and mitochondrial DNA we detected differences in population structure between the species and also between sexes. E roumanicus is mainly restricted to lowlands. Ranges of both species expand and hybridization may play role during formation of reproductive isolation. We did not observed ecological character displacement when using 3D geometric morphometry approaches. Populations in sympatry are more similar than in allopatry. Our data are enhanced by description of parasite fauna of sympatrical populations and we discuss the role which they may play in evolution of the hedgehogs. Study proceeded in New Zealand was based on comparison of...
Phylogeography of Rousettus aegyptiacus in the Mediterranean region
Dundarova, Cheliana ; Hulva, Pavel (advisor) ; Janko, Karel (referee)
The genus Rousettus has distributional pattern unique among fruitbats comprising both Asia and Africa and reaching northern distributional limits of the family in Persia, Arabia and Mediterranean basin. This could be ascribed to the ability of echolocation, consequent cave dwelling, and presumably other site-specific adaptations, which enabled dispersal independent of forest block and surviving in Mediterranean type of climate. Using fastly evolving mitochondrial marker, we aimed to assess genetic variability, its geographic distribution and demography of northern populations of the Egyptian fruitbat (Rousettus aegyptiacus). Mitochondrial network indicates deep genetic divergence between disjunct Mediterranean and eastern African parts of the range. Basal position of Sinaic and Jordanian haplotypes within northern clade indicate important role of these regions in colonization of eastern Mediterranean. Generally, the northern haplogroup is moderately diversified with partial geographic localization of particular haplotypes. Significant isolation by distance pattern suggests relatively pronounced site fidelity of particular colonies, at least in terms of maternal gene flow. Landscape genetics analyses indicate discontinuities in distribution of mitochondrial genetic variability, in some cases correlating with...
Genetická struktura mediteránních populací kaloně Rousettus aegyptiacus
Marešová, Tereza ; Hulva, Pavel (advisor) ; Bryja, Josef (referee)
5 Abstract The genus Rousettus represents the only fruit bat genus distributed both in Asia and Africa reaching northern distributional limits of the Pteropodidae family. This unusual distribution pattern is related to the ability of echolocation, subsequent cave dwelling and probably other thermoregulatory and behavioural adaptations to relatively cold and dry climate. Methods for identification of genetically discrete populations were used in the presented study to acquire better comprehension of historical ways of colonization along with current dispersal and migratory patterns of the Egyptian fruit bat (Rousettus aegyptiacus) in the Mediterranean basin and adjacent range patches. Modern approaches to population and landscape genetics were applied on a dataset comprising 553 individuals from 72 localities using 20 nuclear microsatellites. Our results revealed a significant genetic distance of East African individuals and certain substructure in the northern part of the range. Cypriot population is clearly separated, and - for higher K - the isolation of colonies from Egyptian oases is highly supported. Genetic proximity of south Arabian and Sinai populations contradict current taxonomy of the species. Our findings highlight the role of seas and deserts as barriers restricting gene flow and the evolution...
Population structure of the gray wolf (Canis lupus)
Říhová, Jana ; Hulva, Pavel (advisor) ; Pivnička, Karel (referee)
Gray wolf (Canis lupus), is historicaly the most widespread carnivore with the former range including most of the northern hemisphere. The ambivalent relationship of humans to this predator resulted in extermination of this species in many areas, on the other hand led to the evolution of the dog, unique domesticant with vast phenotypic variation. The effort of conservation biology in last decades resulted in the shift of perception the role of big carnivores in ecosystems, with consequent recolonization of many regions by wolf, including the Czech republic. This changes brings the elevation of interest in this taxon by both experts and laymans. Present review aims to assemble published information regarding distribution, phylogeography, population structure, social and spatial behaviour of the gray wolf. The chapters describing the domestication process of the dog and hybridization with his wild ancestor are included.
Diversity, distribution and genetic structure of the tribe Pipistrellini
Eliášová, Kristýna ; Hulva, Pavel (advisor) ; Fornůsková, Alena (referee)
This literature review discusses phylogenetic relationships within the family Vespertilionidae with a detailed focus on tribus Pipistrellini relations and then the individual genera and species within this tribe. A historical summary of efforts to resolve the phylogenetic relationships within the taxon first on the basis of morphological studies, comparison of karyotype and most recently on the basis of genetic markers. Mitochondrial genetic markers are useful in studying phylogeography, as this paper shows on the example of the Pipistrellus species complex and on species Nyctalus azoreum, Nyctalus leisleri, Nyctalus noctula and Pipistrellus abramus. Furthermore, this work describes the current distribution of individual taxa of tribe, the fossil record and migration behavior of European temperate species in the context of their population structure (also studied in some species using mtDNA and microsatellites) and Annex shows the areas extending all five genera Pipistrellini tribe. Key words: Pipistrellini, phylogenenetics, phylogeography, distribution, population structure
Genetic variability in a population of endangered turtle Orlitia borneensis kept in European zoos
Somerová, Barbora ; Frynta, Daniel (advisor) ; Hulva, Pavel (referee)
Malaysian Giant Turtle (Orlitia borneensis) in poorly known turtle with rapidly descending numbers in nature. Most animals of this species kept in European zoos and included in captive breeding program are confiscates of illegal trade and their locality of origin and taxonomic status are unknown. This study was aimed to assess genetic variation in founders of this population. We sequenced genes for the mitochondrial cytochrome b and found 23 haplotypes. The maximum sequence divergence was less than 1.5% and the phylogenetic structure of the haplotypes was only poorly supported. A close genetic similarity among sampled turtles was further confirmed by a sequencing of the nuclear R35 gene. Thus, the examined population of O. borneensis may be further treated as a single conservation unit.
Phylogeography of Pipistrellus pipistrellus species complex
Chudárková, Adéla ; Hulva, Pavel (advisor) ; Janko, Karel (referee)
(in English) Pipistrellus pipistrellus species complex contains two sympatric species inhabiting Europe and part of West and Central Asia (Pipistrellus pipistrellus s. str, Pipistrellus pygmaeus s. str) and several other lines, isolated in the Mediterranean (North Africa, islands and peninsulas of the Mediterranean Sea). This taxon is a part of the extensive radiation within the genus Pipistrellus, which in today's concept includes about 30 species. Mosaic line of P. pipistrellus complex, located at different stages of diversification and secondary contacts in the Mediterranean biodiversity hotspot, is a suitable model for research on speciation. In this thesis we focused on analyses of distribution, phylogeography, population structure and demography based on mitochondrial data from 323 individuals, representing almost the entire range. Control region of mitochondrial DNA was chosen as a genetic marker. Variability in the 378 pb long fragment acknowledged the existence of several genetically distinct lines whose species status is discussed. Observed fylogeografic pattern confirms the existence of groups of radiation centers in the Mediterranean region. An allopatric speciation was there, two of the lines (P. pipistrellus s. str and P. pygmaeus s. str.) later expanded into Europe and their ranges...
Genealogical structure and breeding behaviour in Pipistrellus nathusii (Mammalia: Chiroptera) model population
Zieglerová, Anna ; Hulva, Pavel (advisor) ; Bartonička, Tomáš (referee)
56 6. SUMMARY This paper summarizes the results of a study in applying molecular techniques to analysis of social biology and the genealogical structure of bats. A population of Pipistrellus nathusii was investigated in the model Protected Landscape Area Trebonsko (South Bohemia). Systematic research of this species has been ongoing there since 1996. Unlike other species, which have been studied using similar research methods, this is a form whose annual life cycle and area distribution are characterized by seasonal long- distance migration of the entire population. Its social structure and mating system are not generally noted in species with similar characteristics. The object of the analysis was a group of 304 individuals, including 45 resident males, 98 adult females and 161 juveniles, captured in 3 Summer colonies during two consecutive seasons. From 15 verified micro-satellite markers, 4 of them, which a displayed standard high level of alelic polymorphism (24-85), were chosen for routine use. It has been shown, that the micro-satellite analysis employed enables highly reliable identification of individuals, and the identification of family relationships. The distribution of documented paternity illustrates that the multiple reproductive effect of certain males and the increased proportion in...

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