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Host specialization and species diversity in Strepsiptera of the genus Stylops
Jůzová, Kateřina ; Straka, Jakub (advisor) ; Malenovský, Igor (referee)
The twisted-wing parasites (Strepsiptera) are entomophagous insect order with cosmopolitan distribution. There are about 600 known species up to date. In spite of this, they have very broad host spectrum. Strepsiptera parasites in seven insect groups (Thysanura, Blattodea, Mantodea, Orthoptera, Hemiptera, Diptera, Hymenoptera). The mutual relationship between genera or even between species are not known, except for the species list and the host specification. Moreover, there is an anambiguous use of their species concept. Some authors consider Strepsiptera as the specialists and they match almost every host species with one separate strepsipteran parasite. The opposite concept is to consider strepsiptera as the generalists. The presence of the crypctic species also affect our understanding of the diversity of Strepsiptera. Therefore, the knowledge of Strepsiptera phylogeny provide us the important information about species diversity of studied group as well as about their coevolution with their hosts. On the basis of molecular analyses of three genes constructed the phylogeny genus Stylops. This genus has the wider spetrum of the host species from other strepsipterans of Stylopidae, It is obvious, that strepsipterans of genus Stylops are mainly specialised on their host subgenus. There was detected two...
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Characteristic population genetics features of animals with parasitic life strategy
Kodejš, Karel ; Straka, Jakub (advisor) ; Synek, Petr (referee)
Organisms with parasitic life strategy are characterized by strong bond to their hosts. Becouse of that can their population history, or more generaly their phylogeny, reflect evolutionary history of the hosts. While with morphological markers alone, coevolution can be examined only at higher, at least species level, the development of molecular techniques, especially usage of selectively neutral markers, provides deeper insight in this problematics. This thesis describes genetic markers used to investigate population dynamics, with emphasis to parasitic animals, and sumarises their advantages, limitations and possible applications. Further it describes statistical methods used in coevolutionary studies, mainly to reconstruct coevolutionary history. It describes basic statistical algorhytms to characterize rate of population subdivision. In the last part it describes parasite and host's life history features, which influence characteristics of coevolution, such as rate of host specificity, complexity of life cycle, host and parasite's mobility, which has impact to final coevolutionary pattern. Keywords: parasitism, population genetics, genetic markers, coevolution, biostatistics, microsatellites
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Nesting behaviour and population genetics of solitary bees (Hymenoptera: Anthophila)
Černá, Kateřina ; Straka, Jakub (advisor) ; Žďárek, Jan (referee) ; Paxton, Robert J. (referee)
My thesis is focused on nesting behaviour and population genetics of solitary bees. These two topics, although seemingly unrelated, bring much new information and thus contribute to the better understanding of solitary bee biology that is still insufficiently known. Although the solitary behaviour represents the necessary original state for the evolution of higher sociality or obligate cleptoparasitism, its role is largely unappreciated. Furthermore, intraspecific cleptoparasitism, which is an alternative and facultative nesting strategy in bees, is a probable antecedent state of obligate cleptoparasitism. Although the obligate cleptoparasitism is a very common strategy in solitary bees, the information about the frequency and the occurrence of intraspecific cleptoparasitism in solitary bees is rare. We studied the nesting behaviour of solitary bees to detect different behavioural patterns that could serve as preadaptations to sociality or cleptoparasitic behaviour and we also focused on the detection and description of intraspecific cleptoparasitism in solitary bees. We chose four model solitary species for these studies - Andrena vaga (Andrenidae), Anthophora plumipes (Apidae), Colletes cunnicularius (Colletidae) and Osmia rufa (Megachilidae). We described the behaviour of Andrena vaga at the...
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Reintroduction of butterflies (Lepidoptera)
Štochlová, Tereza ; Sedláček, Ondřej (advisor) ; Straka, Jakub (referee)
The thesis deals with one of the active means of conservation - reintroduction. By this ap- proach, organisms are released in their historical range from which they have disappeared. Re- introductions typically concern vertebrates, that is, however, why this thesis focuses on a group of invertebrates - butterflies (Rhopalocera). The main aim of this work is to carry out a research of previous experiments, evaluate used methods and discover the best way to proceed with reintroduction of butterflies. This process contains many important steps. Firstly, a suitable species must be chosen, that means one that is declining and has limited dispersal abilities. Secondly, an appropriate habitat for releasing organisms must be found - host plants ought to be sufficiently abundant and the area big enough. If the habitat quality is not satisfactory, it can be achieved through management, most commonly by planting host plants, mowing or grazing. Next step is choosing the right donor population. It should be stable, genetically variable, and genetically and ecologically related to the original extinct population. After transfer and release of sufficient number of organisms, it is crucial to carry out a long-term monitoring of the newly formed population and to modify its management when necessary. All methods...
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Selected determinants of population health and their impact on mortality in European countries
Straka, Jakub ; Šídlo, Luděk (advisor) ; Kulhánová, Ivana (referee)
Selected determinants of population health and their impact on mortality in European countries Abstract The thesis focuses on the relationship of lifestyle determinants of men and women in selected European countries in 2014 with their subjective (healthy life years) and objective level of mortality (life expectancy) and their mortality rates to the most common causes. These are ischemic heart disease, cerebrovascular diseases and malignant neoplasm of the trachea, bronchus and lung. Selected determinants of health were physical activity, BMI, fruit and vegetable consumption, smoking and alcohol consumption. The indicator life expectancy in health is most often related to the exact age of 65 years, and therefore this work also focuses on the elderly population. Multiple linear regression was used to examine the effect of selected health determinants on mortality levels. In addition, the thesis explores the development and intensity of life expectancy in the health of men and women in the period 2004-2014. Finally, it addresses whether the European population between the first decade of the 21st century and 2014 saw an increase in healthy life years. The initial source of data is the EHIS and EU-SILC. Due to the chosen methods, it was found that the length of life in health rather stagnated, which is...
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Legal aspects of alternative fuels' use in transport
Straka, Jakub ; Fiala, Zdeněk (referee)
Legal aspects of alternative fuels' use in transport Abstract What connects solar energy, palm oil and the construction of the Nord Stream 2 gas pipeline? All these topics have one common denominator, i.e. alternative fuels. This group of fuels, which is represented by electricity, hydrogen or biomethane, has the ambition to replace fossil fuels and reduce the negative environmental effects of the sectors of the economy where fossil fuels are used - in transport and energy. This thesis focuses on the transport sector and pursues two lines. The first part of the text examines, by using the example of biofuels, natural gas and electricity, whether and to what extent alternative fuels fulfill the purpose of the alternative in relation to oil-based fuels. The principle of energy security and the principle of sustainable development in its environmental and economic aspects are used as a benchmark. In the second part, this thesis pays attention to legal instruments that determine the future of alternative fuels. Specifically, emission limits for passenger cars and light-duty vehicles and financial support for alternative fuels at all stages of their life cycle are analyzed. The purpose of this work is to capture the momentum of the ongoing legislative development in the field of alternative fuels, to try to...
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Evolution of cleptoparasitic behavior in bees (Hymenoptera: Apoidea)
Straka, Jakub ; Vilímová, Jitka (advisor) ; Zrzavý, Jan (referee) ; Yanega, Douglas Andrew (referee)
Cleptoparasitic behaviour is widespread life strategyin bees (Hymenoptera:Apoidea). More than |5oÁof all bee species are obligate cuckoo bees.It is not the only form of cleptoparasitic behaviour in this insect group, but is by far the most common. Cleptoparasitism can be an obligate as well as an occasional life tactic occuring among pollen-collecting bees.The most simple, but rare cleptoparasiticstrategyin bees is theft of supplies. Bees can steal pollen supplies outside the nest (directly from legs of other bees)or inside of conspecific nest.Robbing (inside nest theft) is an obligatory strategyin some eusocíalstinglessbees(Apinae: Meliponini). Usurpation is anotheroccasional life strategyof normally pollen-collecting bees.[t seemsto be quite common, although it is largely overlooked by observers.Individual marking of nesting females as well as inside nest behaviour can reveal several differentusurpation strategies.The most common is nest usurpationsometimes leading to discarding of cells of the preceedingfemale (host).In some casesonly the nestentranceis usurpedand the new owner is not in contact with the host cells; this can be called nestingarea usurpation. The best-studiedkind of cleptoparasitismis brood parasitism.It rarely occures on the intraspecific level, but it is frequent in its...
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Methods of insect body and food marking and their utilization in bees (Anthophila)
Macháčková, Lenka ; Straka, Jakub (advisor) ; Bogusch, Petr (referee) ; Hanus, Robert (referee)
Marking methods represent often an essential part of many studies which target on insect biology. These marking techniques sometimes represent the only possible way to obtain new and important informations. In the first part of the thesis I deal with individual insect labeling, which was used for marking of solitary bees and their nests as a tool of obtaining informations about nesting bee dynamics in aggregation. Our study show that nest owner replacements are very common in all four species. However, a large percentage of the nests were abandoned by the female owners before owner change. Only a part of all the nests were trully usurped on the nesting site. The true usurpations thus represent rather minor part of observed nest owner replacement situations. The bees surprisingly often abandon their nests and found the new ones. The frequent contacts of the females on a nesting site occur as a result of common nest owner replacements. High tolerance of bees to each other together with tolerance of usurpations and low level of aggression may thus represent one of the possible ways towards communality and other types of social behaviour. In the second part of the thesis I focus on the possibilities of food marking in bees. Effectivity of sugar and pollen utilization are not yet fully understood in...
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