National Repository of Grey Literature 40 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Diversity of the geotrupide genus Jekelius (Coleoptera: Geotrupidae)
Sommer, David ; Král, David (advisor) ; Bezděk, Aleš (referee)
The first part of this thesis focuses on the family Geotrupidae, with special focus on the representatives of the genus Jekelius. It summarizes the present and historical taxonomic concepts and phylogenetic relationships within this family. Moreover, the morphology of adults and larvae and the geographical distribution of individual taxa are described. In the section on the biology and ecology of the family, emphasis is placed especially on feeding strategies, breeding behaviour and parental care. The results of this thesis consist of three parts, 1) taxonomy, 2) molecular analyses, and 3) flow cytometry. The first part brings a taxonomic revision of the Jekelius brullei species complex defined here. This part focuses on redescribing each known species, as well as describing additional species not yet formally described. This thesis defines the distribution ranges of each species based on previously published literature and our own data. Molecular analyses performed in this thesis generated a phylogenetic tree including a significant part of the species of the Jekelius brullei species complex. The last part of the thesis presents results obtained by flow cytometry for representatives of the species complex Jekelius brullei and a number of other taxa of the family Geotrupidae. The discussion then...
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)
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...
Beetles on carrion: life strategies and ecological classification
Kadlec, Jakub ; Šípek, Petr (advisor) ; Růžička, Jan (referee)
This work summarizes available information about beetle communities on carrions, their life strategy and ecology classification. Necrobiotic beetles are very important part of the decomposition process and the return of organic mass to the life cycle. We can classify decomposition by several criterions, most commonly by the overall appearance of the carrion and by the species of present insect. Conclusions are different depending on authors. Process of decomposition of carrion is affected by the readiness of access for different species of insect. Insect succession depends on many factors, some factors increase the process and others decrease it. The interrelationships between different colonizators of carrion are very important, this relationship is described by three models of classic success ecology. Necrobiotic insect has specific adaptations for the life on carrion. For this thesis, we have chosen 13 families, which are often discussed in publications. The rest of 190 necrobiotic genuses from 34 families is listed in this thesis with their characteristic ecology.
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
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.
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.
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...
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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