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Actual knowledge on early Paleozoic cryptospores
Fučíková, Kateřina ; Fatka, Oldřich (advisor) ; Kováčová, Marianna (referee)
The goal of the thesis is to summarize the state of art in uderstanding of Cambrian, Ordovician and Silurian cryptospores. The actual knowledge on stratigraphic range, geographic distribution and classification of cryptospores will be summarized. A special attention will be focussed on already published data on cryptospores from the Barrandian area. These data data will be utilised in the following master thesis focussed on study of Cambrian to Silurian cryptospores with application of the low manipulation HF extraction methodology of samples from the Barrandian area. Keywords: cryptospores, Cambrian, Ordovician, Silurian
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Exoskeletal structure and composition in selected arthropod groups of the Prague Basin
Šilinger, Matěj ; Fatka, Oldřich (advisor) ; Weiner, Tomáš (referee)
The thesis is focused on the study of the internal exoskeletal microanatomy of trilobites and phyllocarid crustaceans from Lower Paleozoic rocks of the Prague Basin. Two main methods are used for this study. The first method, etching of polished slices with ethylendiamintetraacetic acid (EDTA) has been used for the study of microanatomy of trilobite exoskeletons; this method is for the first time used on material from the Prague Basin. The second method, maceration in hydrofluoric acid has been used mainly for the extraction of "small carbonaceous fossils". This method is for the first time applied for the study of exoskeletons in phyllocarid crustaceans. Main goal of the thesis is to determine whether the exoskeletons of trilobites and phyllocarid crustaceans found in the Prague basin are suitably well preserved to be studied with above mentioned methods. Key words: arthropods, exoskeletal structure and composition, Prague Basin
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Systematics of eocrinoid echinoderms
Nohejlová, Martina ; Fatka, Oldřich (advisor) ; Polechová, Marika (referee)
This work deals with systematics of eocrinoid echinoderms but also with their morphology and classification within the echinoderms. Two theories concerning systematic of eocrinoid echinoderms are compiled in this work. UBAGHS (1967) suggested the first version of systematics. SPRINKLE (1973) suggested the second one, still used version of systematics. Work is also focused on the occurrence of eocrinoid echinoderms in Cambrian and Ordovician rocks of the Barrandien area.
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Latest Ludlow chitinozoans from the Prague Basin: significanec for correlations and succession during Kozlowskii/Lau extinction events
Vodička, Jakub ; Fatka, Oldřich (advisor) ; Štorch, Petr (referee)
Two sections, Všeradice and Kosov, represent continuous sedimentary succession situated in the Prague Basin. No detailed research on stratigraphical level equal the N. kozlowskii graptolite zone focusing on chitinozoans, has not yet been conducted in the Prague Basin and is also very scarce globally. Limestone beds, examined for chitinozoans, were not very productive. Chitinozoan reaction on extinction is visible, if we compile data from both sections. The pre-extinct chitinozoan fauna is characterized by the Conochitinidae family. Samples from the post-extinct interval contained no chitinozoas. The interval of fauna recovery is characterized mainly by the Eisenackitina genera. In this interval, global zone for the uppermost Ludfordian, represented by E. barrandei, can be confirmed. In agreement with all the published literature, we have not found E. philipi, index taxa of the former global zone in the Prague Basin. E. lagenomorpha appears stratigraphically only slightly below E. barrandei and therefore it cannot substitute E. philipi, as it is used in Baltika region. chitinozoa, Prague Basin, Kozlowskii, Lau, extinction, Ludfordian, stratigraphy
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Association of Turonian echinoids at the Nebužely locality (Bohemian Cretaceous Basin)
Bartušková, Nikola ; Fatka, Oldřich (advisor) ; Ziegler, Václav (referee)
This diploma thesis is focused on morphological studies and taxonomic analyses of small regular and irregular echinoids found at the Nebužely locality; at this locality clastic sediments of Teplice Formation of Bohemian Cretaceous Basin are exposed. Presence of the belemnite Praeaxtinocamax bohemicus makes possible to assign the outcrop to late Turonian. Detailed morphological study of more than one hundred specimens enabled to distinguish four echinoids species (Echinogalerus, Glyphocyphus, Nucleolites, Phymosoma), less favourably preserved and/or very limited material is classified as belonging to two orders (Cidaroida, Holectypoida) and one family (Phymosomatidae), respectively. The next part of the thesis contains a possible palaeoecological reconstruction of the environment at the studied locality. Based on bathymetrically indicative molluscs, a shallow−water palaeoenvironment is suspected for this locality. Key words: echinoid, Bohemian Cretaceous Basin, Turonian
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"Small carbonaceous fossils (SCFs)": state of art
Kovář, Vojtěch ; Fatka, Oldřich (advisor) ; Dašková, Jiřina (referee)
The thesis deals with the problematics of Small Carbonaceous Fossils (SCF). In the first part of the thesis the term SCF is defined and the presentation of the main palynological approaches used for extraction of SCFs follows, together with an explanation of preservation processes of non-biomineralized organic structures in sediments. The explanation of significance for palaeontology and related disciplines is discussed. The main part of the thesis constitutes of descriptions of the individual published SCFs from the late Ediacaran up to the Devonian, together with stratigraphic context and lithology of the published material. The list of taxa, that were possible to identify among obtained SCF material, is included. All the localities of Phanerozoic age are further plotted into paleogeographic maps corresponding with the appropriate periods. The broad scope of SCF's paleogeographic provenance and the possibility of extraction of SCF from a wide spectrum of lithologies, deposited in various sedimentary environments is discussed and the potential of further studies of SCFs is outlined. Key words: organic microfossils and macrofossils, early Paleozoic, taphonomy, palynological preparation methods
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Macroevolutionary and ecological implications of the theory of frozen plasticity
Toman, Jan ; Flegr, Jaroslav (advisor) ; Fatka, Oldřich (referee) ; Mikuláš, Radek (referee)
The frozen plasticity theory is a punctuationalist theory of adaptive evolution. It states that long periods of stasis, during which populations respond to selection pressures only by elastic change in the frequency of already present alleles, alternate in the evolution of sexual species with short periods of plastic evolution, during which alleles can get fixed or eliminated by directed selection. Asexual species are not expected to maintain such high genetic polymorphism in the long term. They should, however, be able to plastically respond to selection pressures throughout their whole existence. This difference between the evolutionary dynamics of sexual and asexual clades has a number of ecological and macroevolutionary implications. Concerning ecology, we could expect different environmental preferences of sexual and asexual species. Accordingly, in our first work that was based on a comparative study, we statistically significantly supported the hypothesis that (ancient) asexual groups of (eukaryotes) inhabit more stable and homogeneous habitats than their related sexual controls. Focusing on actually experienced, i.e. subjective, heterogeneity of the environment turned out to be the crucial factor of this type of research. From the viewpoint of macroevolutionary implications of the frozen...
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SCF in Lower Palaeozoic sediments of the Barrandian area
Kovář, Vojtěch ; Fatka, Oldřich (advisor) ; Brocke, Rainer (referee)
1 Abstract In recent years, the term small carbonaceous fossils (SCFs) has been established to accomodate fragile organic-walled fossils of micro- to mesoscopic size that are usually extracted by means of the 'low-manipulation HF extraction' method. This method has so far only been utilized by several authors and no reports have been published on the usage of the method on samples from the Barrandian area. To test the applicability of the method, samples from the Barrandian area were processed. The samples came from eleven localities representing six stratigraphic units (Paseky Shale, Jince Formation, Letná Formation, Kosov Formation, Daleje Shale and Roblín Member). All the units have been studied before by 'standard' methods of palynological processing. Various previously unreported fossils are described, including wiwaxiid sclerites, putative chaetognath remains and acritarch clusters. Furthermore, it is discovered, that the 'low-manipulation HF extraction' can also be used for extraction of originally calcareous fossils. The pilot study provides a further proof that the 'low-manipulation HF extraction' is a useful tool with the potential to significantly expand our knowledge of fossil assemblages. Key words: Small carbonaceous fossils, Cambrian, Ordovician, Devonian, Barrandian area
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