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Adaptive radiation of the genus Rattus
Skalíková, Hana ; Frynta, Daniel (advisor) ; Mazoch, Vladimír (referee)
Rats are an important group of rodents originating and living mainly in southeast Asia. They are important pests and reservoirs of zoonosis. Yet, about many species we only have basic information. Here, I summarized available information about 66 species of the genus Rattus and 10 species of the genus Bandicota, Diplothrix, Limnomys, Nesokia and Tarsomys. I focused on distribution, ecology and morphology (body lenght, tail lenght, hind food lenght and ear lenght) and their mutual relationships. The body lenght differs beetwen phylogenetic lineages and beetwen habitats. The other morphological characters (tail lenght, hind food lenght and ear lenght) correlated with body lenght. Further, I describe an adaptive radiation of rats. Rats are separated into several lineages, diferring in their geographic distribution and ecology. Moreover, many species are commensal, that is benefiting from close relationship with humans. Commensalism species can be found in several lineages of rats, therefore commensalism probably developped independently more than once. The commencalism was origined several times. I discuse why are some commensal species more successful than others. Key words: adaptive radiation, Bandicota, commensal species, ecomorphology, Rattus, rodents, southeast Asia
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Adaptive radiation of the genus Rattus
Skalíková, Hana ; Frynta, Daniel (advisor) ; Mazoch, Vladimír (referee)
Rats are an important group of rodents originating and living mainly in southeast Asia. They are important pests and reservoirs of zoonosis. Yet, about many species we only have basic information. Here, I summarized available information about 66 species of the genus Rattus and 10 species of the genus Bandicota, Diplothrix, Limnomys, Nesokia and Tarsomys. I focused on distribution, ecology and morphology (body lenght, tail lenght, hind food lenght and ear lenght) and their mutual relationships. The body lenght differs beetwen phylogenetic lineages and beetwen habitats. The other morphological characters (tail lenght, hind food lenght and ear lenght) correlated with body lenght. Further, I describe an adaptive radiation of rats. Rats are separated into several lineages, diferring in their geographic distribution and ecology. Moreover, many species are commensal, that is benefiting from close relationship with humans. Commensalism species can be found in several lineages of rats, therefore commensalism probably developped independently more than once. The commencalism was origined several times. I discuse why are some commensal species more successful than others. Key words: adaptive radiation, Bandicota, commensal species, ecomorphology, Rattus, rodents, southeast Asia
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The Potential of computed tomography in the research of vertebrates
Piskáčková, Anna ; Frýdlová, Petra (advisor) ; Minařík, Martin (referee)
This thesis explores and classifies the capacities of computed tomography (CT) and mainly microcomputed tomography (micro-CT) in vertebrate research. The thesis pursues the application of the method in imaging the particular structures, tries to gain a knowledge as wide as possible about the studied tissues of vertebrates and about the resolution achieved with micro-CT and evaluates the optimal employment of this method. The aim of this thesis is to propose particular structures ideal for employment of this progressive method with high resolution in morphological, ecomorphological and phylogenetical context of research in vertebrate zoology. At present computed tomography is commonly used diagnostic method, which is employed not only in the medical and veterinary practice but also in biological research. The advantage of computed tomography is it's speed and the fact that it isn't invasive. CT and micro-CT can display mineralized tissues but also soft tissues with used of contrast agents. By micro-CT we create accurate three-dimensional projections of little structures. This can be helpful for example in research of spatially complex skulls and skeletons of even very small vertebrates. At first the thesis tries to map the principles of CT and mikro-CT, the history and the potential of the technique...
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Ecological links between morphology and habitat selection in passerines
Bovšková, Denisa ; Hořák, David (advisor) ; Klvaňa, Petr (referee)
The thesis is focused on relations between avian morphology and habitat selection. This is a summary of comparative studies, dealing this problematics in closely related groups of passerines. Generally, we can classify species to two main groups according to habitat preferences. Aerial species have longer wings probably as a result of adaptation on move in the air and open spaces. In contrast, ground species have generally longer legs as adaptation for running on the ground and pedal locomotion. Longer tarsi are also documented in ground species living in vegetation cover. Species which prefer tall vegetation have short leg probably for better move in branches. Less pronounced morphological differences further reflect habitat preferences at smaller spatial scales within habitat types mentioned above. In addition, some studies reveal that morphological variation reported frequently as reflecting adaptations to feeding preferences shows some links to environmental variation (substrate structure) independent of diet composition, such as bill morphology. Powered by TCPDF (www.tcpdf.org)
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Basic ecohydrological evaluation of a small watercourse
Häusler, Martin ; Doležal, František (advisor) ; Kateřina, Kateřina (referee)
At present the words like ecology or enviroment appear on our every step. In this bachelor´s thesis I focused on the part of the enviroment that mak, calledes life on Earth possible, water. In this thesis I carried out an ecohydrological evaluation of the Litovicko Šárecký stream, namely, its lower reaches, called Šárecký stream.
The Šárecký stream begins at the outlet of the water reservoir Džbán, located in the capital city Prague, and flow further through the nature reserve Divoká Šárka, the Tichá Šárka valley and the Šárecké valley. The stream ends in Podbaba, where it joins the Vltava river from the left side.
The EcoRivHab method was chosen for the evaluation. It includes the stream bed zone, the zone of accompanying vegetation belts and the zone of adjacent flood plain. At the same time, the whole basin has been described geologically, pedologically and climatologically
The method is based on dividing the 9.664 km long stream into 26 sections which variable lenght but qualitatively homogenous. One of them, the one least anthropologically influenced, was chosen as a reference for comparison with the others. The field mapping was executed in June 2015 and in November of the same year. I put emphasis on the hydromorphological state of the stream bed, the accompanying vegetation belts and the adjacent flood plain. On the basis of comparison with the reference section, all sections were categorized according to its ecomorphological grade.
In the future, this ecohydrological evaluation can be used as a background for stream restoration plans that may improve the current state.
On the basis of the ecohydrological evaluation, Šárecký stream was classified mostly into the 1st or 2nd ecomorphological grade, which means a natural or next to natural state without signifiant anthropological influence. This grade mostly occurs in the upper part of the stream, while some indicators get worse as the we progress downstream. The worst grade got one section, which was classified into the 5th ecomorphological grade, which means very strong anthropological influence.
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