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Morphological differentiation and distribution of taxa in the Galium palustre group
Dohnalová, Pavla ; Kaplan, Zdeněk (advisor) ; Chrtek, Jindřich (referee)
This work is focused on the polyploid group of Galium palustre. The process of polyploidization has significantly influenced the evolution of angiosperms and in the studied group led to the emergence of 4 cytotypes known so far. Two of the cytotypes are found in the Czech Republic, diploid and octoploid, distinguished as species Galium palustre and Galium elongatum, respectively. Both taxa are mostly considered as species, which differ in quantitative characteristics, but these show considerable phenotypic plasticity. Therefore, the exact extent of morphological variation, precise distribution and ecology of the species are still unknown. The flow cytometry was used to distinguish cytotypes; it also showed variation in genome size and revealed a new dodecaploid cytotype in the Czech Republic. Subsequent morphometric analysis identified characteristics suitable for distinguishing the individual cytotypes. The most reliable are the length and width of a stem, the length of the leaf, the length of the longest branch, the number of leaves in whorls, the length of the inflorescence and the length of the mericarp. Based on these results, herbarium specimens from several herbaria were examined. The results also showed slightly different ecological preferences of cytotypes and their distribution in the...
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Genetic basis of phenotypic variability in domesticated animals
Majerová, Veronika ; Reifová, Radka (advisor) ; Komárek, Stanislav (referee)
Understanding the mechanisms responsible for the origin of morphological variability among different species of animals represents an important goal in evolutionary biology. Origin and changes of the phenotypic variability during the evolution is possible to study in domesticated animals. The domesticated species of animals represent a brilliant model for studying the molecular mechanisms responsible for origin of new phenotypes due to enormous morphological variability of different domesticated breeds, effortless breeding in captivity and frequent knowledge of the genomic sequence. The aim of this bachelor work is to summarize actual findings about concrete mutations which are responsible for the origination of the new morphological characters in the domesticated animals. These findings can help us to clarify how the evolution functions on the molecular level.
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Nonmetric traits in relationship with physical stress with regard to social structure of great moravian population
Buláková, Lucia ; Brukner Havelková, Petra (advisor) ; Píšová, Hana (referee)
In the case of time-consuming or arduous activity the individual bone, modifications of the individual skeleton may occur. Specific activities or movements are predominantly responsible for these modifications and are likely to be carried out for long periods from a young age of the individual. One of these modifications is considered to be some of the so- called non-metric traits on the postcranial skeleton. Special attention is being paid to changes of the articulation facets and changes in some muscular or ligaments' binding areas which are considered to be possibly related to excessive physical stress, occurring through the lifetime (squatting position). With respect to the frequency of 30 postcranial non-metric traits 293 skeletal remains in the Great Moravian population from the settlement agglomeration Mikulčice-Valy (9th - 10th century) have been compared. The primary goal of this research was to determine the frequency of non-metric traits and to verify the relationship with sex - age or the potential laterality differences in the case of bilateral traits. Then, based on the variability of non-metric traits, two different socio-economic groups were compared - the castle (burial site III. church) and the hinterland (burial sites Prušánky and Josefov). The highest incidence of traits was...
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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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Population differentiation of Ochrophytes
Mensová, Anna ; Jurdíková, Katarína (advisor) ; Kulichová, Jana (referee)
This bachelor thesis deals with a differentiation of populations of Ochrophytes (photosynthetic Stramenopiles). Natural populations can differ in many aspects and their differentiation is observed on several levels. Ecophysiological and morphological differences are very often caused by phenotypic plasticity, which is a flexible answer to changing conditions of habitats. Genetic differentiation could express an adaptation to the local environmental conditions. The adaptation and a long-term isolation of populations are considered to be the leading factors in genetic differentiation. The other factors contributing to genetic differentiation are random evolutionary events such as founder effect or genetic drift. Detailed studies of populations lead to uncover the factors that cause the differentiation of populations as well as they contribute to the understanding of speciation mechanisms. The thesis compiled the information about different types of variability among populations within the classes of Ochrophytes.
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Searching for the origin of high-altitude endemic harebells from Campanula rotundifolia agg. in central Europe.
Folbrová, Magdaléna ; Šemberová, Kristýna (advisor) ; Trávníček, Pavel (referee)
Complex Campanula rotundifolia agg. is rich in endemic species, especially in the high- elevated mountain ranges. Extreme climatic conditions in the subalpine habitats can lead to a convergence in plant's morphology between plants isolated in different mountain ranges. Because of the lack of morphological differentiation, it is very difficult to reconstruct the evolutionary history of bellflowers C. scheuchzeri from the Alps, C. bohemica from the Krkonoše Mountains and C. tatrae from the Western Carpathians. A similarity in morphology and the same ploidy level can suggest vicariance from a large area of an ancestor species. However, regarding the continuous morphological variation, the high-altitudinal endemics could have originated by local adaptation from originally low-land species. DNA-ploidy level and genome size were detected by flow cytometry. Taxonomically important characters were found using multivariate morphometric analysis. The phenotypic plasticity of the taxon C. tatrae was tested by a cultivation experiment. Genetic structure of the studied species was revealed using molecular marker - microsatellites (7 variable primers). Studied taxa were tetraploids, but some possessed different genome size. The morphological differentiation was mainly due to characters like calyx lobes length...
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Nonmetric traits in relationship with physical stress with regard to social structure of great moravian population
Buláková, Lucia ; Brukner Havelková, Petra (advisor) ; Píšová, Hana (referee)
In the case of time-consuming or arduous activity the individual bone, modifications of the individual skeleton may occur. Specific activities or movements are predominantly responsible for these modifications and are likely to be carried out for long periods from a young age of the individual. One of these modifications is considered to be some of the so- called non-metric traits on the postcranial skeleton. Special attention is being paid to changes of the articulation facets and changes in some muscular or ligaments' binding areas which are considered to be possibly related to excessive physical stress, occurring through the lifetime (squatting position). With respect to the frequency of 30 postcranial non-metric traits 293 skeletal remains in the Great Moravian population from the settlement agglomeration Mikulčice-Valy (9th - 10th century) have been compared. The primary goal of this research was to determine the frequency of non-metric traits and to verify the relationship with sex - age or the potential laterality differences in the case of bilateral traits. Then, based on the variability of non-metric traits, two different socio-economic groups were compared - the castle (burial site III. church) and the hinterland (burial sites Prušánky and Josefov). The highest incidence of traits was...
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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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