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Magnetic orientation in mammals
Tejmlová, Kristýna ; Němec, Pavel (advisor) ; Vácha, Martin (referee)
Earth's magnetic field can provide animal with both directional and positional information. The ability to perceive and utilize information extracted from the geomagnetic field is called magnetoreception. Magnetoreception mechanisms remain largely unknown. Three main hypotheses are currently supported by experimental evidence. The light-independent mechanisms are based either on electromagnetic induction or on biogenic magnetite. The light-dependent mechanism is based on specific chemical reaction between radical pairs. Perception of the geomagnetic field facilitates both long- and short-distance orientation of animals. Some animals exhibit the magnetic alignment, i.e., spontaneuos preference for a certain geomagnetic direction. Another manifestation of magnetoreception is magnetic compass (polarity- or inclination-based, depending on species), which enable an animal to determine the azimuth, i.e., the angle between the direction of motion and geomagnetic field vector. Magnetic map sense enable an animal to determine its position and direction to the goal destination, most likely utilizing the inclination and the intensity of the geomagnetic field as navigational cues. Magnetic orientation of mammals seems to be a widespread phenomenon. Light- independend, polarity compass has been reported in...
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Bird and Mammal Taxidermy
Tuzová, Lucie ; Řezníček, Jan (advisor) ; Štěpán, Jiří (referee)
This thesis deals with the preparation of dermoplastic materials of birds and mammals. They are described in detail specific methods of preparation from the collection of material to its final treatment. The first section summarizes the theoretical knowledge concerning preparation of dermoplastic models and osteological material. The second part is dedicated to knowledge survey of high school and primary school students concerning recognition of birds and mammals dermoplastic models. The results are processed by descriptive statistics. Keywords: taxidermy, dermoplastic models and osteological material, skulls, teeth, birds, mammals.
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The catalogue of the mammalian fauna of pleistocenne localities in Prague area
Havlová, Tereza ; Mazuch, Martin (advisor) ; Kadlecová, Eva (referee)
More than a hundred sites were in Prague in the past, where skeletal remains of Pleistocene mammals had been found. Most of these sites were brickyards or sand pits. These pits were in operation during the second half of the 19th century and first half of the 20th century. Many awards were found during construction works as well. Most of researchers attended only several most famous sites at the time of the findings. The catalog summarizes the basic known information about majority of Prague localities and includes a list of taxa wich were found there. Key words: Prague, locality, mammals, Pleistocene, brickyards, sand pits
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Metabolism of uric acid during mammalian evolution
Mančíková, Andrea ; Krylov, Vladimír (advisor) ; Stibůrková, Blanka (referee)
Uric acid is the end product of purine metabolism of humans and some higher primates. In other mammals enzyme urate oxidase is capable to further convert uric acid to allantoin. During evolution of primates several mutations in urate oxidase gene had occured, led the enzyme to decrease its activity or to complete loss of function. What was the initial impetus for the utilization of uric acid and what biochemical traits of uric acid led to a tendency to retain a major of this metabolite production in the bloodstream? Uric acid has antioxidant capabilities and it is scavanger of free radicals. Increased levels of uric acid in blood has an effect on acute and chronic elevations of blood pressure. It is possible that hyperuricemia helped to maintain blood pressure under low-salt dietary conditions of primates during the Miocene. This mechanism probably have allowed to stabilize bipedalism our ancestors. Uric acid has an important role as a neuroprotector. As inhibitor the permeability blood-brain barrier, uric acid limits the infiltration of undesirable substances to the neurons and prevents central nervous system against the formation of inflammatory diseases. Such as neurodegenerative diseases may be caused by reduced serum uric acid levels. Uric acid protects against peroxinitrite damage tissues in the...
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Enamel cover of the mammalian teeth: structural, functional, developmental and phylogenetic aspects.
Hanousková, Pavla ; Horáček, Ivan (advisor) ; Němec, Pavel (referee)
Specificities of the mammalian teeth and their enamel coat with particular re- spect to the autapomorphies establishing the mammalian organization. Basic structural and organizational levels of the enamel histology (nanocrystals, elementary crystallites, prismatic enamel, IPM, schmelzmuster, ultimate characteristics of particular dentitions). Basic survey of comparative data: characterization of enamel of mammals in particular clades and a brief summary of their specificities. Concluding remarks on current state of knowledge and per- spectives of further study. 1
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Factors influencing flight-initiation distance in reptiles and the comparison with endotherm vertebrates
Fictumová, Tereza ; Frýdlová, Petra (advisor) ; Sedláček, Ondřej (referee)
The fleeing behaviour is one of the most common antipredatory strategy. It is intensively studied in many groups of animals. The flight-initiation distance (FID) is used for quantification of fleeing behaviour. The FID represents the distance between a prey and an approaching predator in which the prey starts fleeing. The FID is also used for quantifying of preys fear. The factors influencing FID in reptiles are: temperature, habitat, refuge availability, foraging strategies, predator behaviour etc. I discovered some factors which are different for mammals and birds. The most important difference is the ectothermy in reptiles vs. the endothermy in mammals and birds. Another difference is parental care, alarm calls and grouping. The factors as an influence of predator, refuge availability or type of habitat seems to have very similar or the same impact on FID for both groups.
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Hunting in the early Middle Ages
Vaníčková Žemličková, Andrea ; Klápště, Jan (advisor) ; Žemlička, Josef (referee)
(in English): The thesis is devoted to hunting in Early Middle Ages in Czech Republic. The work summarizes the current knowledge of written sources and iconography. This knowledge are compared with zooarchaeological dates from sites dating to the Early Middle Ages. The thesis deals with the hunting law, hunting reserves and the hunting organization. The major part of this work is focused on game and its use. A portion of game on several hill forts and rural sites was also studied because hunting was not available for all social classes.
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