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Diversity and distribution of scorpions (Arahnida: Scorpiones)
Plíšková, Jana ; Šťáhlavský, František (advisor) ; Kůrka, Antonín (referee)
This thesis is devoted to species diversity and biogeography of Scorpiones order. Bachelor work is presenting basic problems of this area and major split in higher classification of scorpions, which is still not firmly defined. In the work is also provided an overview of the current 15 families, to whom is the scorpions order divided by classification proposed by Soleglad & Fet (2003), including their distribution, the number of families and species they cover. Factors which had or still have an impact on the expansion of scorpions are also discussed. Described factors, which affects the distribution and diversity of scorpions, are: continental drift and Quaternary climate change (historical aspects) and temperature, parthenogenesis and human factor (environmental aspects). These factors influenced the biogeography of scorpions at different taxonomic levels, in different evolution time scale and on differently sized territories.
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Molecular variability and distribution of the Frustulia rhomboides species complex (Bacillariophyceae)
Urbánková, Pavla ; Kulichová, Jana (advisor) ; Bešta, Tomáš (referee)
Recent use of molecular methods to revisit taxonomically problematic diatom species revealed severe limitations of morphological species concept. Characterization of diatom species which was based solely on the morphology of their frustules often generated too broad species boundaries which inevitably lead to wrong conclusions about their ecology and distribution. Widespread opinion that many diatom species are cosmopolitan generalists resulted in a theory that dispersal of diatoms is not limited by geographical distance. However, a number of recent studies showed that dispersal of diatoms is governed by the same rules which matter for macroorganisms. Proposed master thesis addresses the topic of diversity and dispersal in diatom species complex Frustulia rhomboides sensu lato in Europe and New Zealand. Results suggest that: (1) although revealed molecular variability in this complex shows clear ecological and biogeographical signal, it is not correlated in morphology. This is another support to general need for adoption of different species concept in diatoms. (2) A considerably uneven ratio in species diversity of genus Frustulia found in ecological similar habitats in Europe and New Zealand supports the idea that diatom dispersal is limited and stressed the need for studies dealing with biogeography.
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Gondwanian element of Latin American Flora
Potůčková, Anna ; Stančík, Daniel (advisor) ; Kvaček, Jiří (referee)
The concept of plate tectonics accepted during 20th century fundamentally changed general opinion on the origin of Latin American flora. It was found, that South America formed a part of the ancient continent Gondwana. This continent was covered by a unique flora until 100 million years ago. Actual disjunction of widely distributed tropical taxa present in South America originated after disruption of that original flora distribution. It was deduced that the separation of South America from Gondwana finished about 100 million years ago and led to the isolation of their flora until the formation of the Isthmus of Panama about 3 million years ago. However, recent studies based on molecular clock approaches shows that the exchange of biota between South America and rest of the World was possible several times in different ways before the closure of the Isthmus of Panama. The reevaluation of our opinion about the gondwanan origin of Latin American flora based on advanced molecular analysis is the aim of this work.
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Taxonomy, ecology and biogeography of aquatic and limno-terrestrial diatoms (Bacillariophyta) in the Maritime Antartic Region
Kopalová, Kateřina ; Nedbalová, Linda (advisor) ; Sabbe, Koen (referee) ; Jüttner, Ingrid (referee)
Diatoms (Bacillariophyta) are one of the most diverse algal groups in the Antarctic Region and play a dominant role in almost all freshwater and terrestrial ecosystems. Despite this overall occurrence, little is known about the diversity, ecology and biogeography of this group in the Maritime Antarctic Region. The main objective of this thesis is therefore to define the taxonomical, ecological and biogeographical characterisation of aquatic, semi- aquatic and moss-inhabiting diatom communities from two islands in the Maritime Antarctic Region: James Ross Island and Livingston Island, located on opposite sides of the Antarctic Peninsula. In this study, a total of 250 samples from three different habitat types (lakes, streams & seepage areas and mosses) from Byers Peninsula (Livingston Island) and Ulu Peninsula (James Ross Island) have been analysed. Using light and scanning electron microscopy, a rather diverse diatom flora composed of 178 taxa, belonging to 43 genera has been identified. Although even until recently, it was generally accepted that the Antarctic diatom flora was mostly composed of cosmopolitan taxa, several new species could be described as a new for science during this PhD study (a reflection of this work is presented in chapters 2 & 3 and in Appendices). Habitat type and...
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Small mammals in diet of barn owl in the Eastern Meditarranean
Šindelář, Jiří ; Horáček, Ivan (advisor) ; Anděra, Miloš (referee)
The extensive material of skeletal remains of mammals from a diet of barn owl in the eastern Mediterranean has been processed and evaluated with different techniques of chorological and morphometric analysis. At least 8400 individuals of 45 species of insectivores, rodents and bats were found in our total collection of samples, which represents a significant portion of fauna of the region. We have evaluated a chorological composition of the taphocoenoses and the interregional differences, manifested primarily by differences in the representation of satellite and accessory elements. We found a highly significant impoverishment of the isolated island taphocenoses (Cyprus, Karpathos, partly on Crete), where Cricetidae, Arvicolidae, C. leucodon etc. are missing. On the other hand the essential part of the dominance structure takes up the Rattus rattus, which acts here as an invasive species, significantly more successful than in the ragged continental contexts. The species diversity of the examined samples is positively correlated with the geographic latitude (taphocenoses of the northern regions are significantly richer) and negatively with the island effect and the degree of aridization. The morphometric analysis of the three most abundant species of Soricidae within the studied region showed...
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Phylogenetic, morphological and ecological context of microevolution in pennate diatoms
Veselá, Jana ; Neustupa, Jiří (advisor) ; Řeháková, Klára (referee) ; Vanormelingen, Pieter (referee)
Visual assessment of discontinuities in the morphological features of diatom cells has been widely used in the discovery and delimitation of diatom species. However, a multidisciplinary approach to species-level taxonomy has revealed hidden diversity within the traditional diatom morphospecies. Consequently, this work examined both the natural and clonal populations of diatoms by diverse traditional and modern approaches, in order to assess the diversity, ecology, and distribution of diatom species. Although a detailed investigation of natural diatom samples was confounded by uncertain morphological boundaries between the traditional diatom species, it recognized that the diversity was relatively high; even one new diatom species was described using the morphological species concept. The multivariate statistical analyses showed that the variation of natural communities of traditional diatom morphospecies reflected differences in the local environmental conditions, as well as microhabitat heterogenity within a region. Since each diatom morphospecies is most likely a complex of sibling species, the two model traditional morphospecies were investigated, in order to assess morphological variation, genetic diversity, and/or the reproductive compatibility of monoclonal cultures. Even though isolated...
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Biogeography, diversity and substrate specificity of aeroterrestrial green algal genus Klebsormidium (Streptophyta)
Ryšánek, David ; Škaloud, Pavel (advisor) ; Mareš, Jan (referee)
Filamentous aeroterestrial green algae genus Klebsormidium occurs in a very wide range of freshwater and terrestrial habitats. Recent results of molecular investigations led to the finding that the diversity within this genus is far greater than expected on the basis of the morphological features, and that the traditional phenotypic species concept is insufficient. I tried to differentiate phylogenetic lineages within the genus Klebsormidium by thein different biogeographical distribution and environmental preferences. Since no study dealing with the biogeographic pattern of aeroterrestrial algae was so far undertaken, another aim of this work was to test validity of the protist ubiquity model in aeroterrestrial habitats. I studied this issues based on the chloroplast rbcL molecular marker. Based on the obtained data I found that the geographic definition of particular Klebsormidium lineages turns out to be unusable because of the cosmopolitan occurrence of almost all genotypes. However, the data obtained from the substrate specificity study shows that clear ecological preferences exist within the genus Klebsormidium and could be simply used to define different lineages within the genus.
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Diversity, distribution, phylogeny and ecology of the genus Micrasterias (Desmidiales)
Trumhová, Kateřina ; Šťastný, Jan (advisor) ; Bestová, Helena (referee)
The genus Micrasterias comprises one of the most beautiful organisms. It attracts, due to its spectacularly shaped cells, the attention of scientist and amateur biologist almost for almost 200 years. This thesis summarizes the current knowledge about these extraordinary organisms. The first part deals with the morphology and the life cycle of these algae. They share a unique type of reproduction (conjugation) with the other representatives of the class Zygnematophyceae. The second part concerns phylogeny of this genus. Several morphologically distinct species have been revealed with the aid of molecular phylogenetic methods to belong to the genus Micrasterias. A polyphasic evaluation of three species complexes within this genus also revealed an extensive hidden diversity. The last chapters summarize the knowledge about the influence of hidden diversity and accelerated morphological evolution on our understanding of diversity and biogeography of these organisms.
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Phylogeography and population structure of two loach species (Teleostei: Nemacheilidae) in Southeast Asia
Dvořák, Tomáš ; Bohlen, Jörg (advisor) ; Říčan, Oldřich (referee)
The freshwater fish species Schistura robertsi and Paracanthocobitis zonalternans belong to the family Nemacheilidae, which is distributed across whole Eurasia and with one species in northeast Africa. P. zonalternans occurs in lowland habitats through western Southeast Asia from Central Myanmar until northern Malaysia. The distribution area is of biogeographic interest, because it crosses several known biogeographic barriers, namely the border between Indian and Indochinese freshwater fauna along the Salween River, the Isthmus of Kra, the Krabi - Surat Thani line and the Kangar - Pattani line. In the present study, around 250 specimens of P. zonalternans from 62 localities across the whole distribution area were investigated using genetic (nuclear and mitochondrial sequences), morphologic and geologic data. The genetic data reveal the existence of seven major clades within the analysed material, each of them with a distinct geographic distribution area and only few cases of overlap, but with occurrence of some cases of secondary contact. Divergence time estimations suggested that P. zonalternans is about 18 my old, and a biogeographic analysis located the region of origin in the Tenasserim region (nowadays southern Myanmar). The global sea level fluctuations seem to have had a strong impact on the...
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Diversity and biogeography of protists
Ryšánek, David ; Škaloud, Pavel (advisor) ; Kulichová, Jana (referee)
My bachelor thesis consists of two parts. The first part is a literature review, the second part is a practical one, which contains the results of my own research. The first part of my thesis is devoted to the literature review, dealing with two current views on biodiversity and biogeography of protists. The first theory, model of protist ubiquity is described in a few points and illustrated by several examples. Likewise is presented the second hypothesis of moderate endemicity model. In conclusion, both models are compared and advantages and disadvantages of each theory are pointed out. In the second part of this thesis I briefly describe the genus Klebsormidium, which is followed by an optimization of molecular methods to study biodiversity and biogeography of this genus.
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