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History of Sorex araneus group in the western Palearctics (Mammalia, Soricidae)
Cestrová, Aneta ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
The bachelor thesis reviews the literary data on the species group Sorex araneus, one of the most important component of the Holoarctic communities of small ground mammals. It provides a brief account of the life history patterns of the group (activity pattern, foraging strategy, reproduction) responding to demands of extremelly high energentic metabolism. The evolutionary setting of the group is characterized by a specific complex of sex chromosomes XX/XY1Y2, and enormous extent of chromosomal polymorphism due to multiple Robertsonain translocations producing a large number of chromosomal races with distinct combination of metacentric chromosomes. The interpretations on history of the group provided by molecular phylogenetics are compared with phylogenetic signals of the abundant fossil record of the group. Despite its richness (more than 300 fossil assemblages) the interpretation of fossil record is still confused and calls for a detailed re-examination. Key words: Sorex araneus, fossil record, phylogeography, Pleistocene, Palearctic
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Genus Sicista (Mammalia, Rodentia, Zapodidae) in the Western Palearctics: diversity, phylogeny and paleobiogeography.
Lišková, Tereza ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
The bachelor thesis surveys literary data on taxonomy, distribution, phylogeny and range history of the genus Sicista, one of the least known clade of Palearctic rodents. The genus composes a monotypic family Sminthidae, a basal branch of the superfamily Dipodoidea recorded since the late Eocene. Fourteen recent species are currenty distinguished. Most of them colonize small vicariant ranges distributed from East Asia to Central Europe with peak of species diversity in Central Asia and Caucasus regions. Also two taxa occupying large ranges (S.betulina, S.subtilis) including eastern parts of Central Europe rank among the rarest local specis throughout most of their ranges. The European fossil record (more than 150 Quaternary sites) indicate quite a more extensive distribution covering diverse regions of the Western Europe during the Pleistocene and the early Holocene. Yet, the species identity of many fossil records remain doubtful due to quite indistinct morphological differences among particular species. The discrimination criteria and range history in Central Europe are discussed in details with particular attention to the fossil record available from the Czech Republic and Slovakia. Key words: Sicista, phylogeny, range history, diversity, taxonomy, Western Palearctics
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Evaporative water loss in terrestrial vertebrates
Demešová, Jana ; Starostová, Zuzana (advisor) ; Vohralík, Vladimír (referee)
Evaporative water loss affects physiology, ecology and evolution of individual organisms. This wok summarizes the knowledge about water loss in main groups of terrestrial vertebrates. In addition to physiological processes, it also follows evolutionary trends through adaptations created as a barrier against the water loss or as a method of cooling by evaporation. From an ecological point of view, it examines whether these adaptations have enabled some of them to inhabit extreme habitats. The topic of water loss by evaporation interferes with other topics such as thermoregulation or metabolism. Key words: evaporation, water loss, aridity, thermoregulation, metabolism, vertebrate
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Ecological and phylogenetic effects determining variation of growth patterns in amniotes
Stanková, Veronika ; Frýdlová, Petra (advisor) ; Vohralík, Vladimír (referee)
Growth is a process during which organs or the whole body enlarges. It can be modeled by using growth models and curves. The work is mainly focused on the explanation of two types of growth - the determinate growth, which is finished after the reaching of the sexual maturity, and the indeterminate growth which on the other side continues even after the reproduction or after the reaching of the sexual maturity. In the literature there is generally stated that birds and mammals are characterized by the determinate growth, amphibians and reptiles have the indeterminate growth. The aim of this work was to analyze the current available literature relevant to the growth and to evaluate the above mentioned statements about the growth of the vertebrates. The ecological and the phylogenetic effects influencing the growth, the physiological regulation and the mechanism of the growth are summarized in this work. Powered by TCPDF (www.tcpdf.org)
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Racoon dog (Nyctereutes procyonides) in Central Europe: history of range expansion and current state of knowledge
Pyšková, Klára ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
The thesis is about the raccoon dog (Nyctereutes procyonoides), a canid invasive in a large part of Europe. It describes its distribution in native and invaded range, the history of colonisation, ecology and social behaviour, as well as its impact in the invaded range. Available knowledge is summarized, with main focus on central Europe. The native distribution range of the species is in eastern Asia. The animals were first brought to the European part of the former Soviet Union in the first half of 20th century for breeding at fur farms, and later being released into the wild for hunting. The raccoon dog colonised 1,4 million km2 over the next 50 years, and became an established carnivore common in many European countries. A number of factors influenced the successful invasion; an opportunistic feeding strategy and high habitat adaptability; repeated and numerous introductions over a long period of time, resulting in a high genetic variability; the ability to hibernate; low numbers of predators; the tendency to wander, sometimes to quite distant areas; and high intraspecific tolerance. The environmental and economic impact of raccoon dog seems to be rather low, and the most dangerous aspect of its invasion is the transmision of infectious diseases, mainly rabies.
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