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Ecology and courtship behaviour of the wolf spider genus Alopecosa (Araneae: Lycosidae)
Just, Pavel ; Dolejš, Petr (advisor) ; Žďárek, Jan (referee)
In my bachelor thesis, Czech members of the wolf spider genus Alopecosa are discussed. Literature review summarizes our knowledge in ecology of wolf spiders, their life histories, phenology and habitat preference. I concentrated on reproduction of wolf spiders of the genus Alopecosa, especially on their courtship behavior. Recently, spider courtship is studied with focus on multimodal signalling. The review also contains remarks about spiders life cycles, copulation and parental care. Research of courtship of the genus Alopecosa is sligthly neglected, especially when we consider achievements gained by study of the American wolf spiders of the genus Schizocosa. It is necessary to know the taxonomy of the genus Alopecosa, thus some taxonomical remarks about current systematics and phylogeny of family Lycosidae are outlined
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Arachnophobia and the cause of fear of spiders
Říha, Roman ; Dolejš, Petr (advisor) ; Vlček, Kamil (referee)
Fear of spiders is largely widespread, and in some cases may even grow into a phobia. Negative attitude towards spiders can be found already in the mythology of some peoples. This attitude is often in the Western culture. It is interesting that this fear persists even though there are very few spiders which are able to endanger human life. There are more possible causes of arachnophobia, including classical conditioning, information transmission and impact of disgust emotions. Right the disgust seems to be the probable explanation of spider phobia. Relevance fear is documented by a list of dangerous spiders to humans. Some spiders are in fact able to endanger human health by toxins contained in their venom. Basic questions to deal with are validity of human fear of spiders and possible causes of this negative relationship.
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The consequences of low dispersal capability on diversity and distribution of spiders.
Schweiner, Ladislav ; Opatová, Věra (advisor) ; Dolejš, Petr (referee)
Spiders represent a highly diversified group. In terms of their dispersal capability, they can be classified in two categories: vagile and sedentary. Vagile spiders, most of the Araneomorphae infraorder lineages, are better adapted for dispersal thanks to their ballooning capability and generally more active lifestyle compared to the sedentary spiders, mostly belonging to the infraorders Mygalomorphae and Liphistiomorphae. The manner of dispersal and its efficacy represents a key factor for the colonization of new habitats and maintaining gene flow among the populations of the same species. Limited dispersal capability is responsible for the tendencies to local endemism in sedentary groups. This thesis aims to summarize our knowledge about the dispersal capabilities of sedentary spiders and the effect of vicariance and allopatric speciation on their distribution. The thesis provides a brief overview of dispersal barriers and evaluates their effect on the gene flow among the populations. The data proceeding from studies focused on selected sedentary spider lineages suggest that dispersal barriers have a strong negative effect on gene flow among their populations. Limited gene flow thus leads to genetic diversification and subsequent speciation. Key word: Dispersal, dispersal barriers, endemicity,...
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Phylogeny and diversity of harvestmen suborder Laniatores
Marešová, Alexandra ; Hiřman, Matyáš (advisor) ; Dolejš, Petr (referee)
This bachelor thesis summarizes the general knowledge about phylogenesis, diversity and distribution of harvestmen from the suborder Laniatores. Until recently, phylogenetic relationships of this suborder were very few studied, but thanks to a recent studies they are still improving. The suborder Laniatores now includes 41 families, which are divided into ten superfamilies. An overview of distribution of individual families of the suborder Laniatores is also given in this work and so are factors influencing it. From abiotic factors there is humidity, temperature, climate, and altitude. Among biotic factors, the distribution may be influenced by the type of vegetation or by the human, where it is mainly the introduction of invasive species. The greatest emphasis is placed on morphological differences between individual families. The biggest differences can be observed on their bodies, especially in the form of different numbers and types of sclerotized protrusions. Keywords: harvestmen, Laniatores, phylogenesis, biogeography, biodiversity, morphology
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Study on dynamics of spinning apparatus of some wolf spiders (Araneae: Lycosidae) during their life cycle
Dolejš, Petr
Current knowledge of the spinning apparatus comes namely from studies on orb web spiders and their relatives, whereas that of wolf spiders were more or less neglected. Therefore, developmental changes of the spinning apparatus of four wolf spiders were studied throughout their life cycles. Each of these lycosids possesses stenochronous life cycle with similar number of instars (7-10) but of different length (1-3 years). There is only one period of reproduction in spring/summer in all four species. Sperms are being formed just after the final moult; diplotene in some species is peculiar. The courtship behaviour reflects the microhabitat occupied by the concrete spider species; the copulations are species specific. Ontogeny of the spinning apparatus of developing spiderlings was observed: The spinning apparatus initiate its function in the first instar. Secondary ampullate, all piriform and all but four aciniform glands are tartipore-accommodated; they do not moult in situ. The tartipores, vestigial structures corresponding to spigots of the previous instar, appear on the spinning field starting with the second instar. Tartipore-accommodated glands play roles also during proecdysis and their evolution corresponds with the way how do the spiders secure themselves when moulting. Hence, the not yet...
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Karyotype variability of Myriapoda
Kášová, Adéla ; Šťáhlavský, František (advisor) ; Dolejš, Petr (referee)
The bachelor thesis deals with diploid numbers of chromosomes, their morphology and chromosome mechanism of sex determination in four classes of the subphylum Myriapoda. Attention is also paid to mutual phylogenetic relationships within the subphylum. A review of the literature shows the degree of examination of cytogenetic characteristics in individual classes, which is still very low, especially in the classes Pauropoda and Symphyla, and within the class Diplopoda there are still a large number of orders where we completely lack this information. Cytogenetic analyzes revealed a total range of chromosome numbers for: Pauropoda 2n = 12 - 27, Symphyla 2n = 11 - 18, Chilopoda 2n = 14 - 54 and Diplopoda 2n = 8 - 30. Within all four classes, there are both morphologically undifferentiated sex chromosomes and XX/XY and XX/X0 systems. In addition, the X1X1X2X2/X1X20 system is mentioned for the order Spirostreptida. Only a small number of species from the orders Glomerida, Calipodida, Julida, Spirostreptida, Lithobiomorpha and from family Scutigerellidae were able to identify the occurrence of NORs. The work also managed to identify some discrepancies between the data of different works, which shows that especially some older studies were based on poor observation of chromosomes in the karyotype. Key...
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Aphidophagy among polyphagous predators
Valdecká, Miriam ; Řezáč, Milan (advisor) ; Dolejš, Petr (referee)
Aphids are among the most widespread insect pests in agroecosystems. So far, significant attention has been paid to their natural enemies, especially to specialized predators and parasitoids. There is less information about the influence of polyphagous predators, especially spiders and ground beetles. Therefore, the aim of this thesis is to summarize the knowledge about this topic. And focus on the advantages and disadvantages of aphidophagy in polyphagous predators. Key words: Aphid, aphidophagy, polyphagous, spider, carabid, predator
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Methods for storing and archiving zoological tissue collections, and identification based on DNA barcoding
Aghová, Tatiana ; Benda, Petr ; Brejcha, Jindřich ; Dolejš, Petr ; Kyralová, Eva ; Mlíkovský, Jiří ; Moravec,Jiří ; Šanda, Radek ; Štundl, Jan ; Tkoč, Michal ; Vondráček, Dominik
Fulltext:  PDF; PDF; PDF; PDF
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Dissolved Air Flotation – From Pilot Plant to Full Scale Implementation
Dobiáš, Pavel ; Hlaváč, Jaroslav (referee) ; Janda,, Václav (referee) ; Vávrová, Milada (referee) ; Dolejš, Petr (advisor)
The thesis deals with the use of dissolved air flotation (DAF) in water treatment technology in the Czech Republic. It summarizes the knowledge gained at pilot plant studies as well as the experience with full-scale flotation units which have been built in potable water treatment plants in the Czech Republic in years 2006-2018. This thesis provides a broad background of experimental studies of a modern separation process, which does have great advantages in the removal of natural organic matter and microorganisms from water in the drinking water treatment industry. In this thesis, there are presented some examples of the excellent efficiency of the microorganisms removal, both under the experimental conditions as well as water treatment plants, which were improved by DAF units installation in full scale. In addition to the high separation efficiency, it is shown, how DAF units could influence the subsequent separation steps as for example filtration through the granular media. The negative influence of the pre-ozonization on the DAF separation efficiency in Hradec Králové WTP is demonstrated too. The results of the pilot experiments support the idea, that the key condition for high removal efficiency is the optimal coagulation process chemistry. Design of pilot experiments was based on the factorial planning theory and some results are discussed in this thesis. The very big portion of the pilot experiments was made for estimating of the full-scale DAF design parameters before the water treatment plants reconstruction phase
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The impact of algal organic matter on coagulation of other impurities present in surface waters
Barešová, Magdalena ; Pivokonský, Martin (advisor) ; Ambrožová, Jana (referee) ; Dolejš, Petr (referee)
Drinking water treatment is facing an adverse impact of algae especially when they extensively decay and release cellular organic matter (COM). As the character and consequently the removal efficacy of COM depends on the individual species, the thesis compares algal organic matter (AOM) derived from four common phytoplankton species: green alga Chlamydomonas geitleri, diatom Fragilaria crotonensis, and cyanobacteria Microcystis aeruginosa and Merismopedia tenuissima. To evaluate the differences between extracellular and cellular organic matter, we monitored the growth of those organisms and compared AOM obtained at different growth phases. As COM is not only difficult to coagulate, but also hinders the coagulation of other substances, the thesis investigates the effect of simultaneous coagulation of COM with other impurities present in surface waters: kaolin, humic substances (HS) or cyanobacterial cells of M. tenuissima. Coagulation behaviour was studied by the jar tests performed with single components and their mixtures with and without a coagulant (ferric or aluminium sulphate). Special emphasis was paid to proteinaceous COM of M. aeruginosa; to enhance the removability of proteinaceous matter we implemented pre-oxidation. Coagulation effectively removed turbidity (up to 99%) either of clay or...
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