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Stable isotopes in study of diet in Ursidae, including fossil taxa.
Marková, Aneta ; Horáček, Ivan (advisor) ; Čermák, Stanislav (referee)
Composition of food of members of the family Ursidae is often discussed topic. Up to now, however, there is some uncertainty about the trophic level of some fossil groups. Very useful method which helps us to determine the trophic level of the fossil species and determine the relative proportion of plant and animal components in the recent ones is the analysis of the stable isotopes. This study summarizes present state of methodological approaches and possibilities of use of the stable isotopes 13 C and 15 N in the study of foraging ecology of bears. The results of the analysis of stable isotopes are presented together with results obtained by other methods. Attention is paid to groups for which the relevant isotopic data are available, with special emphasis on the cave bear, which trophic level is evaluated on the basis of stable isotopes analysis as well as in the evolutionary and nutrition context.
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Non-invasive conservation genetics of ursids
Šrutová, Jana ; Hulva, Pavel (advisor) ; Hájková, Petra (referee)
This bachelor thesis is devoted to non-invasive genetics and molecular ecology of particular species of ursids(family Ursidae). This carnivore lineage is quite diversified, particular species inhabit different environments from arctic regions to tropical rainforests and they also differ in trophic niches. As remnants of megafaunal communities that occupy important positions in ecological networks, they are often referred as keystone, umbrella and flagship species which are important in conservation biology. During the Anthropocene, the existence of particular species of Ursidae is more or less influenced by human activities or their impacts. Although nature conservation has managed to stabilize the abundance of some species, habitat loss and human- bear conflicts are becoming more frequent as a consequence of the expanding human population. The aim of the work was to review the research of population structure and demography especially using non-invasive genetic techniques in particular species with intention to implement the acquired knowledge into brown bear research in the Western Carpathians in the future. The chapter about non-invasive sampling is focused to this model species. Non-invasive genetics is important tool for research especially in large, rare, highly mobile and elusive species and...
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Stable isotopes in study of diet in Ursidae, including fossil taxa.
Marková, Aneta ; Horáček, Ivan (advisor) ; Čermák, Stanislav (referee)
Composition of food of members of the family Ursidae is often discussed topic. Up to now, however, there is some uncertainty about the trophic level of some fossil groups. Very useful method which helps us to determine the trophic level of the fossil species and determine the relative proportion of plant and animal components in the recent ones is the analysis of the stable isotopes. This study summarizes present state of methodological approaches and possibilities of use of the stable isotopes 13 C and 15 N in the study of foraging ecology of bears. The results of the analysis of stable isotopes are presented together with results obtained by other methods. Attention is paid to groups for which the relevant isotopic data are available, with special emphasis on the cave bear, which trophic level is evaluated on the basis of stable isotopes analysis as well as in the evolutionary and nutrition context.
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Concept of species in bears (Ursidae): practical, historical, and theoretical viewpoint
Wagner, Jan ; Fejfar, Oldřich (advisor) ; Sabol, Martin (referee) ; Musil, Rudolf (referee)
The present thesis surveys topic of taxonomic diversity and phylogeny of bears (Mammalia, Ursidae) and aspects of its contextual setting under effects of changing conceptual and methodological viewpoints. This problem is studied from several perspectives. The historical perspective is represented by a critical overview of the history of specific and infraspecific classification of bears with special respect to mutual influences of this classification and theoretical concepts of species accepted in particular periods. The perspective of material approach is exemplified by a material-based study of taxonomical and phyletic status of selected Pliocene to Middle Pleistocene ursine taxa. Along with deconstruction of some traditional hypotheses this produced a model explaining species diversification in ursine bears and its discussion in terms of factual relevance of included background concepts. In the pre-evolutionary period the bear species were usually understood broadly, as incipient immanent entities, yet exhibiting obvious certain infraspecific variability. This was established using definitions of varieties (mostly not identifiable with present subspecies or infraspecific taxa) considered as unstable modes of particular species. Although, in the post-Darwinian period, the concept and taxonomic...
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