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Parthenogenetic lizards of the genus Darevskia as an evolutionary model
Abramjan, Andran ; Frynta, Daniel (advisor) ; Janko, Karel (referee)
Several parthenogenetic lineages occur within the lizards of the genus Darevskia (Sauria: Lacertidae) which are endemic to southern Transcaucasus. High level of heterozygosity, cause by thein hybrid origin, is one of the crucial aspects of thein evolutionary potential, as well as the asexual reproduction. Heterosis on one side is in the opposition to the outbreeding depression and genetic uniformity of the clones on the other side. Aim of this work is to evaluace if these aspects influence viability of parthenogenetic species and differ them from the sexual ones. We chose the amount of asymmetries as a measure of developmental instability, which we studied on three meristic characters. We also evaluated the pattern of asymmetries in lateral blue spots, which are of signaling importace in lacertid lizards. Our results suggest that there isn't significant difference between parthenogenetic and sexual species in developmental stability, but the sexual ones are more sensitive to population changes. Absence of males may have perhaps the greatest influence on coloration, resulting in loss of symmetry in the blue spots.
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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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Are silkworm males capable of producing vitellogenin?
VRCHOTOVÁ, Markéta
The eggs of the silkworm, Bombyx mori, obtained from the ovaries implanted into male hosts are able to complete embryonic and post-embryonic development in spite of the very low amount of vitellogenin. Using polyacrylamide gel electrophoresis, I searched for differences between the protein spectra of eggs from standard females and the eggs from ovaries implanted into the males. I also examined the variability of protein spectra in the eggs of several parthenoclones. I confirmed great differences in the egg protein spectra between the eggs from females and those from the ovaries implanted into males. Both heavy (180 kDa) and light (42 kDa) subunits of vitellogenin were present in the eggs from females but only the heavy subunit of vitellogenin was found in the eggs developed in ovaries implanted into male hosts. Interesting interactions between transplanted gonads and the host milieu were observed. All compared parthenoclones contained similar patterns of the main yolk proteins but differed slightly in some high-molecular weight protein fractions.
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