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Development of endemic freshwater ichthyofauna of Greece
Kyralová, Eva ; Vukićová, Jasna (advisor) ; Švátora, Miroslav (referee)
The Balkans is one of the hot spots of biodiversity, and is known for a high diversity and endemism of freshwater fishes. The development of Greece was significantly affected by the climatic, geologic and orogenetic events resulting in high concentration of freshwater fish endemism. Some of the important historical events were the emergence of land bridges during the early Oligocene and Miocene, through which freshwater fishes dispersed to the Balkans from Asia and subsequently to Africa, the freshwater phase of the Paratethys sea or Alpine orogeny, which began 65 million years ago, and which gradually formed the Greek mountain systems, leading to a long-term isolation of local freshwater ichthyofauna and subsequent speciation. Other major events include Messinian salinity crisis and Pleistocene climate oscillations. Most of the freshwater fish families occurring in Greece most probably originated in the Southeast Asia, from where they colonized the Balkans by several routes. These colonizations took place repeatedly at different times and by different routes. The dispersion of freshwater fishes from Asia to Europe through Siberia started before the uplift of the Ural Mountains about 33 million years ago and continued until Pliocene. Another important colonization route from Asia was via the...
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Aquatic fauna of karstic fields in the Balkans
Doulíková, Tereza ; Vukićová, Jasna (advisor) ; Kalous, Lukáš (referee)
Dinaric Karst region of the Balkan Peninsula is one of the hot spots of biodiversity, and it is characterized by a high degree of endemism of freshwater fishes. Numerous geological and climatic events have influenced the formation of the area and speciation. Karst poljes are the specific features of Dinaric Karst. They represent a specific ecosystem full of endemic species, where hydrogeological processes play an important role. The periodic flooding appears on poljes. It leads to activation of various underground channels and their interconnection. Twenty two endemic fish species have adapted to this regime. They live in underground waters or in surface waters part of the year and they can migrate between poljes through karst channels. They show significant reduction in size and change in complexity of scaliness. Scales are small and they are barely visible in some species. All these species and abundant underground karst fauna are threatened primarily by pollution, habitat destruction, and drainage of poljes.
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The role of high-altitude habitats for speciation of central European endemics from the genus Campanula
Folbrová, Magdaléna ; Šemberová, Kristýna (advisor) ; Reif, Jiří (referee)
Mountain environment plays an important role in plant's life. Extreme conditions lead to continuous speciation accompanied by a complex processes e.g. geographical isolation (variation) or polyploidization. These processes can be studied by using a suitable model plant, represented in this thesis by selected mountain endemic bellflowers species belonging to Campanula rotundifolia agg. These species appear to be morphologically very similar but they are supposed to be of different origin. Mountain ecosystem is considered to be one of the most diverse and the most valuable environment for nature conservation. It hosts many endangered plants as well as plants protected by law. From the model group, these plants are represented by Campanula bohemica Hruby, Campanula gelida Kovanda and Campanula rotundifolia subsp. sudetica (Hruby) Soó. This thesis aims to sum up the up the current knowledge about a high altitude environment and endemism and to give a description of speciation mechanisms leading to the variability of mountain Campanula species. Further descriptions of their endangerment level, conservation and origin are also given. The subsequent MSc Thesis, introduced in the last part of this thesis, aims to reveal the origin of Czech and Slovakian mountain Campanula endemics. It is mainly focused on...
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Evolutionary history of tetraploid representatives Galium pusillum group (sect. Leptogalium) in central Europe. Allopatric differentiation of Czech endemic species G. sudeticum
Knotek, Adam ; Kolář, Filip (advisor) ; Chrtek, Jindřich (referee)
The presented study tries to reveal the evolutionary history of polyploid complex Galium pusillum aiming on a rare czech endemic species G. sudeticum, an ideal model to study allopatric speciation in the context of Central European (post)glacial development. The species G. sudeticum grows in Krkonose Mts. and on serpentines in western Bohemia (Slavkovský les) more than 200 kilometers away. Our morphological and molecular data suggest a clearly different history of its two isolated areas. The populations in Krkonose Mts. are probable relics of mountainous species G. anisophyllon which was there on its northern border of occurence and hybridized with lowland species G. valdepilosum during postglacial vegetations shifts. This fact is well supported by intermediate position of Krkonose Mts. populations in both morphological and molecular AFLP analyses and by sharing the same chloroplast haplotype with geographically close lowland populations. On the other hand the serpentine lowland populations in western Bohemia are both morphologicaly and genetically indistinguishable from G. valdepilosum. Distinct genetic lineage of few populations belonging to G. valdepilosum (incl. one traditionaly referred as G. sudeticum) was found in western Bohemia and Bavaria, located on relic stands (calcareous and serpentine...
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Differentiation within the Carlina vulgaris complex in central Europe
Mašková, Hana ; Kaplan, Zdeněk (advisor) ; Chrtek, Jindřich (referee)
The Carlina vulgaris complex includes in central Europe several forms with specific morphology, ecology and distribution. Their mutual relationships and ancestry are unclear. This fact leads to many different views on their taxonomy. The critically endangered endemic taxon C. biebersteinii subsp. sudetica was described from the Czech Republic. Its differentiation from other central-European populations has not been studied yet. For this reason, my following master thesis will focus on taxonomic re-evaluation of this complex by means of investigation of genetic and morphological variation. Powered by TCPDF (www.tcpdf.org)
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Endemic plants of the Sudeten Mts., with emphasis on the taxonomically controversial Primula elatior subsp. corcontica
Konečná, Veronika ; Suda, Jan (advisor) ; Knotek, Adam (referee)
The endemic species of the Czech Republic still present a hot topic. Effective research of this topic means understanding of factors which create and influence endemism. With the exception of the Alps and the Carpathians, endemics are relatively very rare in Central Europe. In the Czech Republic they are concentrated mainly in subalpine (alpine) areas in the High Sudetes. Majority of the Czech endemics is of relatively recent origin. They have not well differentiated yet and so it is difficult to taxonomically evaluate them. Endemics of the High Sudetes have probably originated in Holocene with the exception of apomicts, e.g. species of genus Hieracium, which have likely originated even earlier. The origin of most of the Sudetes endemics was possible due to geographic isolation of small populations called peripatric speciation. Peripatric speciation is probably responsible for the origin of taxonomically uncertain endemic species Primula elatior subsp. corcontica, which is a subspecies of highly variable P. elatior. In the Czech Republic occur three subspecies of P. elatior - subsp. corcontica, subsp. elatior and subsp. tatrensis. These subspecies are differentiated in the morphology of leaves and in their distribution. The description of P. elatior subsp. corcontica was based on morphological...
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Risk assessment of interspecific hybridization between endemic Campanula bohemica and widespread C. rotundifolia s.l.
Hanušová, Kateřina ; Suda, Jan (advisor) ; Krahulec, František (referee)
The thesis deals with phenotypic, ploidy and genetic variation of two Campanula species occurring in the Krkonoše Mts., namely the endemic C. bohemica and widespread C. rotundifolia subsp. rotundifolia. For comparative purposes subspecies sudetica of the latter species was also included. The main aim was to get insight into population structure and assess the threat of interspecific hybridization to the survival of the endemic bluebell. Flow cytometry, distance-based morphometrics and molecular analysis were used to address these questions. Three distinct groups of fluorescence intensities were revealed by flow cytometry, corresponding to DNA diploids, tetraploids and pentaploids. While diploids morphologically matched the nominate subspecies of C. rotundifolia, tetraploids corresponded either to C. rotundifolia subsp. sudetica or C. bohemica. Most populations from the Krkonoše Mts. were uniform although a sympatric growth of diploids and tetraploids was encountered in 12 populations. Only two pentaploids individuals, most likely of hybrid origin, were found, which indicated that interspecific hybridization is much less common than previously assumed. The two tetraploid taxa were distinguished by molecular markers. A combination of flow cytometry and molecular analyses thus allowed reliable...
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Microevolutionary processes in the Czech endemic Campanula bohemica
Hanušová, Kateřina ; Suda, Jan (advisor) ; Vít, Petr (referee)
The genus Campanula L. - bellflower - is the largest group of the family Campanulaceae with a subcosmopolitan distribution and poorly resolved infrageneric classification. The evolutionary history of the genus has been shaped by a number of microevolutionary processes, including interspecific hybridization, genome duplication and geographical isolation, that resulted in the genesis of several endemic or geographically restricted species. The centre of endemism in the Czech Republic lies in subalpine altitudes of the Jeseníky and the Krkonoše (Giant) mountains, where three endemic taxa can be found: C. gelida Kovanda, C. rotundifolia L. subsp. sudetica (Hruby) Soó and C. bohemica Hruby. Despite their evolutionary and biogeographical value, there is a lack of information about their phenotypic variation, population structure, evolutionary history and processes acting in their populations. A critical assessment of these topics would require application of modern biosystematics tools. Campanula bohemica is an endangered neoendemics of higher altitudes in the Krkonoše Mts., closely related to C. scheuchzeri Vill., native to the Alps. The endemic species often grows in sympatry with related and morphologically similar C. rotundifolia. The incidence of intermediate morphotypes suggest that both species can...
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Taxonomy and variability of selected Sorbus taxa
LEPŠÍ, Martin
This thesis is a biosystematic study focusing on the taxonomy and variability of selected taxa of the genus Sorbus, one of the most diverse and taxonomically complicated plant groups in Europe. Classical and modern biosystematic methods - comparative study, chromosome counting, analysis of nuclear microsatellite markers, flow cytometry, and traditional multivariate and outline morphometric analyses were used to assess the morphological, karyological and genetic variability of the genus. The final synthesis of these approaches led to the description of several new taxa (species, hybrids and a subgenus) and the correction of several taxonomic misinterpretations. To reveal ongoing evolutionary processes responsible for the generation of the observed variability, the reproductive modes of 42 Sorbus taxa were examined using flow-cytometric seed and pollen screens. Apart from revealing major trends, the study estimates the frequency of rare events and provides several novel conclusions that are relevant both specifically to Sorbus/Rosaceae and to apomixis in general.
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Population biology of Dianthus arenarius subsp. bohemicus
Špalová, Zuzana ; Raabová, Jana (referee) ; Münzbergová, Zuzana (advisor)
Dianthus arenarius subsp. bohemicus is a critically endangered plant which is endemic in the Czech Republic. The estimated number of plants is about 1400 (observation from 2008). In the Natura 2000 project Dianthus arenarius subsp. bohemicus is included among priority species. The major cause of threat of this species is probably change in land use - tree planting and the abandonment of traditional pasturage. Despite of conservation effort since seventies, population still declined until 1999 when large-scale sod-cutting was carried out. This management lead to rise of number of plants from 200 to 1400 clusters. In 2008 Ministry of the Environment of the Czech Republic approved Action plan forf Dianthus arenarius subsp. bohemicus which is now implemented. Part of this plan is a study of population dynamics of the species. This study will be an object of my Diploma thesis. This bachelor's thesis is a comprehensive literature survey about Dianthus arenarius subsp. bohemicus. In the literary overview itself there are summarized results of works, incl. the practical application of the data in conservation programs.
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