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Karyotype evolution of the family Araneidae
Pajpach, Filip ; Král, Jiří (advisor) ; Sember, Alexandr (referee)
Orb-weavers (Araneidae) are a diversified spider family comprising more than 3,100 species in more than 170 genera. Together with 13 other families, they con- stitute to superfamily Araneoidea. The presented thesis focuses on karyotype evo- lution of Araneidae, including its comparison with a related family Tetragnathidae. The results obtained from 19 araneid and four tetragnathid species confirm previ- ously postulated hypothesis that the ancestral karyotype of Araneoidea (including Araneidae) consists of 24 acrocentric chromosomes in males, including two acro- centric X chromosomes of system X1X20. However, there is a tendency of 2n decrease in some araneids due to centric fusions. In these cases, centric fusions affected most autosomes (and sometimes gonosomes as well); number of chromosome pairs de- creased from 11 to six. Three independent reduction events were detected in this thesis. Furthermore, pattern of nucleolar organizer regions (NORs) was studied in this thesis using fluorescent in situ hybridization, since data on evolution of this marker are scarce in spiders. Striking variability in NORs number was discovered, ranging from one to 13 loci. Remarkably, multiple centric fusions were always ac- companied by considerable increase of NORs number. In araneids and tetragnathids possessing...
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Biogeography of arachnofauna of the Alps
Šilhavá, Alena ; Šťáhlavský, František (advisor) ; Řezáč, Milan (referee)
This bachelor thesis gives a summarizing overview of the biogeography of arachnofauna of the Alps. It covers five orders of arachnids residing in the Alps, namely scorpions (Scorpiones), pseudoscorpions (Pseudoscorpiones), palpigrades (Palpigradi), harvestmen (Opiliones) and spiders (Araneae). The work is focused on the distribution of endemic and subendemic species of these orders of arachnids and on factors that can influence their distribution and total diversity in the Alps. It turns out that temperature and humidity are important factors. Pseudoscorpions occur more frequently in warmer areas at lower altitudes, while especially scorpions of the genus Euscorpius (Alpiscorpius) and harvestmen are more tolerant to areas with a lower temperature, while harvestmen especially require sufficient humidity. For spiders in the mountains of the Alps total species richness and density decreases mainly from open land to the forest. Total diversity in the Alps has also been influenced by temperature oscillations during the Quaternary climatic changes and different positions and types of refugia. This is apparent at the species closely related to soil environment, such as palpigrades or cave pseudoscorpions of the family Syarinidae. Key words: biogeography, the Alps, endemic, Scorpiones, Pseudoscorpiones,...
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Succession of spider assemblages in quarries of Bohemian Karst
Siegelová, Eva ; Kubcová, Lenka (advisor) ; Korenko, Stanislav (referee)
In this thesis, the succession of spider assemblages in five limestone quarries of different ages in Bohemian Karst has been studied. The main goal of this paper was studying changes of spider assemblages along successional gradient. Furthermore, different environmental factors affecting spider communities and also assemblages of spider communites in different terraces of the quarry have been studied. Standardized methods (pitfall traps, hanging desk traps, shifting leaf litter, sweeping of herb vegetation, and beating shrubs) have been used for recording the highest possible richness of spiders. The results showed that position of the terraces and the age of the quarry do not affect species richness and density. Species density of epigeic spiders increased significantly with number of the plant species. The results showed that spiders do not have their own succession, but they are following vegetational succession. The environmental factors which affect species composition of spiders from the pitfall traps are positon of terraces, shading and moss cover. Although the age of the quarry was insignificant for spiders from pitfall traps, every quarry was inhabited by different spider communities. Shrubs and tree-dwelling spiders showed correlations with the age of the quarry. Data recorded from...
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Comparison of Arachnids from caves in selected parts of Balcanic and Alpine-Carpathian regions
Škopek, Zdeněk ; Šťáhlavský, František (advisor) ; Růžička, Vlastimil (referee)
This work presents comparison of cave arachnids in selected areas of Balcanic and Alpine-Carpathian regions. The work contains basic characteristics of studied regions, also characteristics of cave environment and explanation of important terms often used in relation to these habitats. Further, it concludes basic knowledge of all recent orders of arachnids to cave environment. It contains also detailed study of the best investigated groups of arachnids, and tries to explain some aspects, which influence the biodiversity on the matched area. Powered by TCPDF (www.tcpdf.org)
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Sublethal effect of agrochemicals on \kur{Pardosa} sp.
KRIŠTOFOVÁ, Lucie
In the last decades, there has been a growing interest in studying particular those arthropods who have an important role in agroecosystems. For example, they are natural enemies of pests and therefore they are considered to be beneficial organisms. However, these beneficial arthropods may be negatively affected by the application of chemicals under the management of agroecosystems and their potential to inhibit pests can be significantly reduced. Such organisms certainly include spiders which occure in abundant numbers practically in all types of terrestrial habitats including agricultural ecosystems where they have a role of very important predators. Therefore, the thesis focused on current issues of pesticides, especially from the view of their negative effects on behavioral modification of beneficial invertebrate organisms in agricultural crops. The theoretical part is devoted to a brief characteristics of pesticides, their sublethal effects on non-target organisms and the importance of spiders as natural regulators of pests in agroecosystems. The practical part describes the experiment whereconventionally used agrochemicals were tested the influence of the herbicide and desiccant Basta 15, the Arrest preparation and their combination (mixture Basta 15 + Arrest) on spiders genus Pardosa. I focused on the side effects of these solutions, specifically on the modification of predatory behavior and on the mortality of spiders. It has been shown that agrochemicals affect the predation successfulness of spiders. From the short term and the long term point of view, it has been shown that spiders treated with the tested preparations killed less prey than the individuals in the control group which were treated only with distilled water. The dependence of mortality and the number of killed prey on the size and sex has not been proved. Preparations Basta 15 and the mixture caused significantly higher mortality of spiders. The Arrest preparation did not increase the mortality.
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Interactions between spiders (Araneae) and their prey
Nerpas, Marek ; Korenko, Stanislav (advisor) ; Kysilková, Kristýna (referee)
Spiders (Araneae) are predators utilizing many strategies for hunting their prey. Their diet is often extensive. To obtain food, many various interactions occur among the spiders, and some species are not even afraid to hunt over other spiders. In the first two chapters, I describe the environment of spiders. I focus on the basic classification of spiders, following by an overview of the most important families in Central Europe and their division into the weavers of different types of cobwebs, and spiders who do not hunt through the webs but have a similar style of hunting, in hunting groups (guilds). Further on, the work deals with intraspecific interactions between spiders, such as competition, cannibalism or cooperation that influence the success in hunting prey and consequently the success in survival of spiders. In the last two chapters I deal with the interactions in the framework of the hunting groups, and between different hunting groups that affect other species of the ecosystem and are a driving force in shaping animal communities.
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Characters used for determining of spiders (Araneae)
KRIŠTOFOVÁ, Lucie
This bachelor thesis focuses on a current issue of classifying spiders into their families. The incorrect recognitions of a family are often caused by inappropriate choice of morphological features and their ambiguous characteristics for determination usage. In a literary review, various morphological characters of spiders used for their determination to families are summarized and described. Subsequently, two Czech keys were tested by respondents, which provided a view of the steps and features causing difficulties in classifying spider families. Thus, I outline both unquestioning acceptance of features from older sources and the fact that their usage is not always a reliable tool for determination. Often neglected is the attitude of inexperienced observers who look upon the spider body inexpertly, not being influenced by arachnological traditions, and therefore, with a certain dose of exaggeration, objectively. This is the reason why the research was done mainly with the help of amateur public. In the final parts of the bachelor thesis, I both discuss problems that emerged and were recorded during the observation and recommend suitable improvements concerning the classification keys.
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Ecological education in nursery school
MRÁZKOVÁ, Kristýna
Mrázková, K.: Ecological education in nursery school Insects and spiders as model taxon within ecological education in nursery school An educational proposal for work with pre-school children aimed at closer familiarization with life of insects and spiders has been elaborated. The submitted proposal has been developed into eleven incorporated sections connected through a motivational fairy-tale "Little George among beetles". Six of these sections have been tried out and in terms of field-test results and gained experience the implementation of remaining five is now being arranged. Work and grapho-motive sheets for children of pre-chool age have been also designed and presented with each topic.
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