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Preferences of the main groups of pollinators for the functional floral traits
Malá, Karolína ; Janovský, Zdeněk (advisor) ; Hadrava, Jiří (referee)
This bachelor thesis summarizes the preferences of the main functional groups of pollinators towards floral traits of plants. Due to coevolution and mutual selection pressures, these two life forms have begun to adapt to each other and develop traits on which the future of their life depends. The plant seeks to attract its pollinators, thus ensuring efficient pollen transfer or reproduction for its species. Attractants are used to motivate visitors to its flowers. These attractants provide pollinators with either direct rewards (food, shelter, brood) or rewards in the form of sensory perceptions (colour, scent, morphology). Recently, it has become apparent that flower colour, morphology and the type of food reward offered by the flower have the greatest influence on pollinator choice. Based on preferences towards attractants, we can organize several functional groups whose representatives have the same or similar choice preferences. Key words Pollination syndromes, pollinator, selection pressures, plant traits, coevolution, preferences, fidelity, diptera, coleoptera, lepidoptera, hymenoptera, birds, colour, morphology, rewards
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Vliv klimatických podmínek na rozklad těl obratlovců v zimních měsících
Horáková, Jana
This work deals with decomposition of the vertebrate body during the winter months. The introductory, theoretical part is devoted to the vertebrate decomposition processes and the insect body settlement. It also describes individual insect families with their representatives on cadavers, and the influence of climatic conditions on their development. Also mentioned isdiapauza, which contributes to the level of cold resistance of insects. At the site of Brno, 7 experimental fields were set up, the object of the experiment was chickens. The research ran from 02.12.2016 to 30.03.2017. At weekly intervals, muditoring of cadavers based on ongoing decomposition and later on the collection of necrophagous fauna in connection with current climatic conditions took place. During the experiment, 11 species of necrophagous fauna were found on cadavers, 5 of them from Diptera and 6 from Coleoptera. Determination of insects took place at the Prague Institute of Criminology by pplk. Ing. Hana Šuláková. The results were compared with those of other authors with whom they basically agree.
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Výskyt a druhové zastoupení řádu brouci (Coleoptera) na Mohelenské hadcové stepi
Polášková, Alexandra
The diploma thesis is focused on the assessment of the difference in the occurrence of invertebrates in the monitored locality in the Czech Republic and on the evaluation of anthropogenic and environmental influences on the invertebrates. In the introduction, the characteristics of the order of the beetles, most important representatives of the studied area and anthropogenic impacts on the biodiversity of the beetles are described. The monitored territory was Mohelenská hadcová step, which is located in the Vysočina Region. The collection of beetles took place at five sites during the vegetative season in 2016 and 2017. The beetles were determined and evaluated on the basis of individual localities and ecological indices. The results were compared with our and foreign literature. At the end of the thesis are given the context and the possible effects on the occurrence of invertebrates.
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Growth and sexual selection in selected representatives of scarabaeoid beetles (Coleoptera: Scarabaeoidea).
Vendl, Tomáš ; Šípek, Petr (advisor) ; Knapp, Michal (referee) ; Skuhrovec, Jiří (referee)
Flower chafers are well-known beetles with apparent sexual dimorphism. Yet, in contrast to other groups of scarab beetles, only little attention has been paid to various aspects of this phenomenon. It concerns also sexual dimorphism in size, which is very common in animals. Although ultimate causes of sexual size dimorphism have been extensively studied, the developmental mechanisms are still only poorly understood. We investigated proximate causes of sexual size dimorphism in several differentially dimorphic flower chafer species. We found that in highly dimorphic species the dimorphism started to develop already in the first instar and tended to accumulate through successive larval development. In contrast, the sexes in species with a relatively low dimorphism diverged in size during only one instar. Moreover, we found variability not only in when the dimorphism arises during development, but also how: sex-related differences in both the instar duration and average growth rate were the proximate causes of sexual size dimorphism. In addition, we showed that the sexes may differ also in growth trajectory - males had relatively longer period of rapid growth than females, even in cases where the absolute development times were similar in both sexes. Further, we focused on systematic survey of sexual...
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Evolutionary history, systematics and biogeography of Southern Hemisphere hydrophilid beetles (Coleoptera)
Seidel, Matthias ; Fikáček, Martin (advisor) ; Gomez-Zurita, Jesus (referee) ; Gimmel, Matthew L. (referee)
The research presented in my PhD thesis consists of phylogenetic, biogeographic, taxonomic and ecological research of Southern Hemisphere water scavenger beetles (Coleoptera: Hydrophilidae) with a special emphasis on New Zealand. The introductory chapter provides a brief outline on the break-up of Gondwana and geological processes that shaped New Zealand and its fauna. Furthermore, the diversity of New Zealand Hydrophilidae and worldwide diversity of the hydrophilid subfamily Cylominae and its taxonomic history are illustrated. The scientific part of the thesis contains 4 published papers and 2 manuscripts. The first study recalibrates the Coleoptera time tree, providing new age estimates for the Hydrophiloidea, among others. The new age estimate is implemented in the second study, a phylogenetic study that reconstructs the biogeography of the 'Gondwanan' Cylominae beetles. The Cylominae, whose name was reinstated through nomenclatural priority over Rygmodinae in a separate paper, are found to consist of two tribes, Andotypini and Cylomini. The disjunct distribution of Cylominae is shown to be partly the result of vicariance and partly of long-distance oversea dispersal. The most remarkable long-distance dispersal is that of the only African representative of the subfamily which reached Africa from...
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The role of iridescent and UV reflectant coloration patterns in beetles (Coleoptera)
Vlach, Jan ; Šípek, Petr (advisor) ; Pecháček, Pavel (referee)
The bachelor thesis deals with the role of iridescent and UV reflectant coloration patterns in beetles (Coleoptera). The thesis is divided into two main parts. The first part describes in detail the different types of iridescent and UV reflectant coloration patterns, it deals with the physical origines of coloration and finally it presents examples of beetle species, which possess this types of coloration. The second part deals with the functional perspective of iridescent and UV reflectant coloration patterns. The coloration function is divided into visual and nonvisual part. The part dealing with visual function is focused on interspecific and intraspecific communication, while the part dealing with nonvisial function describes thermoregulation and mechanical function of coloration. Powered by TCPDF (www.tcpdf.org)
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Succession of insect communities inhabiting carcasses of small vertebrates, with emphasis on the beetles
Kadlec, Jakub ; Šípek, Petr (advisor) ; Růžička, Jan (referee)
This master thesis deals with succession and succession mechanisms of beetles (Coleoptera) on carrions of small vertebrates. As a model sample of small carrion a small mouse of weight 20 grams was chosen. In 2014 two experiments occurred. The first one studied the succession of a beetle community in dependence on seasonality and time of death of the sample. The second experiment was aimed to survey the blocking effect of an early insect succession on the final beetle community composition on carrions. It turned out, that during decomposition of the carrion the overall amount of beetles raised equally to the guild of necrophagous beetles. Change of the species spectrum during succession was not statistically confirmed. On the other hand, the effect of seasonality was clear as during the season the abundance and the amount of species increased. The proportion of trophic guilds changed significantly, necrophagous beetles were the most dominant part of the community towards the end of the season. Equally, the taxonomic composition of the community also changed during the season. The seasonal dynamics of carrion beetles was clear; Nicrophorus vespillo (Linnaeus, 1758) and N. investigator Zetterstedt, 1824 showed their peaks in spring and summer while N. humator (Gleditsch, 1767) and N. vespilloides...
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Phylogeny and evolution of habitat preferences of the subfamilies Rygmodinae and Sphaeridiinae (Coleoptera: Hydrophilidae)
Sýkora, Vít ; Fikáček, Martin (advisor) ; Zrzavý, Jan (referee)
Subfamilies Rygmodinae and Sphaeridiinae together form approximately one third of the extant diversity within the family Hydrophilidae (Coleoptera: Polyphaga). Members of both these subfamilies inhabit wide spectrum of aquatic and terrestrial environments including specialized habitats such as phytotelmata, carrion or termite nests. So far, habitat shifts within these subfamilies have been only tested with a limited amount of taxa at the family level. Using a broader sampling and Bayesian and maximum likelihood methods, genus-level molecular phylogenetic analysis and divergence dating were performed. The dataset included 96 taxa, representing all major clades (genus groups) in both subfamilies, sequenced for two mitochondrial and two nuclear genes. A single shift from the aquatic to terrestrial environment in the Middle Jurassic was suggested, thus revealing both subfamilies and all tribes as ancestrally inhabiting decaying plant material and leaf litter. Secondary returns to aquatic habitats were suggested for two lineages of the Rygmodinae and several lineages belonging to tribes Coelostomatini and Megasternini. A single shift to flowers was revealed in the subfamily Rygmodinae. Similarly, single independent shifts to the inquiline lifestyle in tribes Omicrini and Megasternini were revealed. In...
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Sexual selection in Scarab beetles with empahsis to the subfamily Scarabaeinae (Coleoptera: Scarabaeoidea)
Kněnická, Kateřina ; Šípek, Petr (advisor) ; Král, David (referee)
Sexual selection is a very important phenomenon in nature. In this work, I focused on the mechanisms of sexual selection in scarab beetles, with a strong emphasis on group Scarabaeinae (Coleoptera: Scarabaeoidea: Scarabaeinae). The first part is devoted to selection and its classification the sexual reproduction and related effects. I tried to describe the list of forms of sexual dimorphism in individual families and groups of Scarabaeoidea and describe life strategies subfamilies Scarabaeinae. Finally I list the factors influencing the individual the attractiveness in the relation to mating success. Powered by TCPDF (www.tcpdf.org)
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