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Hamsters (Rodentia, Cricetinae) in the Quaternary fossil record of Czech Republic and Slovakia
Lebedová, Klára ; Horáček, Ivan (advisor) ; Wagner, Jan (referee)
1 Abstract The material of hamster remains in the Quaternary fossil assemblages from Czech Republic and Slovakia was analyzed in details with aid of biometric comparisons and contextual analyses focused on stratigraphic position of particular records and structure of the small mammals communities accompanying them. Cricetus as well as small hamsters (Allocricetus-Cricetulus) were recorded in all main Quaternary biozones (MN17-Q4). Yet Cricetus was recorded in few assemblages only mostly just with a single specimen only, except for several Q2 sites and those from the present glacial cycle (with peak abundance in preboreal and boreal). Despite obvious common trends (enlarging size from MN17 to Q3) all samples show roughly the same pattern of dental variation supporting a concept of Cricetus as a monotypic genus with a single species, C. cricetus covering all fossil forms separated as its subspecies. Correspondingly, our results support congeneric status of MN17-Q3 Allocricetus and Q4 Cricetulus, despite separating them as independent species, i.e., Cricetulus bursae and Cricetulus migratorius. Analysis of subrecent samples of C. migratorius from Turkey revealed a very broad span of phenotype variation in extant species covering both the variation framework of extant Phodopus sungorus and metric variation in a...
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Genus Sicista (Mammalia, Rodentia) in the fossil record of central Europe: phenotypic variation, taxonomic structure, range dynamics.
Lišková, Tereza ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
Member of the genus Sicista rank among the rarest and the least known European mammals. They exhibit a number of outstanding specificities (hibernation, aestivation etc.) and extreme capability of a rare range dynamics. Their fossil record is fragmentary and associated with numerous controversies. The present thesis summarizes results of a detailed revision of the fossil record of Sicista from Czech Republic, Slovakia and some other countries. It comprises of about 150 items of the Holocene and Vistualian age as well as from the Middle and Early Pleistocene including earliest records from MN17/Q1 boundary and type material of S. praeloriger from Q1 Betfia. Compared to a sample of extant population, variation dynamics of both metrical and nonmetrical dental traits was examined in details with particular attention to phenotype patterns of particular fossil samples. The results demonstrated extensive amount of both within- and between-population variation and rather limited validity of commonly used discrimination criteria of extant clades. Nevertheless, we succeeded in species identification of considerable part of numerous Holocene and Vistulian records which revealed (i) a range expansion of S. subtilis s.l. during MIS 3 with persistent distribution in lowland regions of Central Europe in the Late...
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Bioacoustic pattern of a bat community: seasonal dynamics of bat communities in the Kruger NP, SAR.
Staňková, Markéta ; Horáček, Ivan (advisor) ; Bartonička, Tomáš (referee)
Analyzes of bat echolocation calls enable to investigate diverse patterns of bat communities without the need for contact manipulation with individuals. The continuous all-night acoustic recordings provide standardised data open to quantitative comparisons and testing effects of diverse contextual factors upon bat community structure. The multidisciplinary project MOSAIK (Monitoring Savanna Biodiversity in Kruger NP) mapping patterns of variation in savanna communities under different spatial and temporal influences includes bats as one of the model groups. At standardized monitoring points of the project (covering 20 different areas, each containing triplet points differing in access to the water surface: permanent, seasonal and the crests without a water source), all-night acoustic recordings of bats were undertaken over two seasons (using Song Meter recorders SM4BAT). All records were analyzed with aid of Kaleidoscope Pro software and cluster identification technique (with an input database developed by Weier et al. 2018 and Taylor et al. 2020) controlled by manual checking. Multiple comparisons of diverse coenologic variables of the particular samples were performed together with testing effects of associated contextual variables (geographic setting and climatic currents, seasons, vegetation,...
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Carnivores and ungulates in Mid-European landscape
Podhůrská, Marie ; Horáček, Ivan (advisor) ; Hart, Vlastimil (referee)
Carnivores and ungulates in Mid-European landscape Abstract The paper provides a brief survey of abundance status and population trends for most species of large mammals distributed in the Czech Republic. Abundance dynamics during past decades is discussed based on hunter statistic records covering both yearly data on hunting bags and standardized accounts of spring abundance of game animals from gamekeeper's evidence. It is documented that most of the species including regularly hunted ungulates, most of mesocarnivores and currently expanding species (racoon dog, racoon) are undergoing fluent population density increase contrasting with decrease of abundance of smaller to medium sized forms (hare, rabbit, marten, polecat). The respective data suggest that recently the community structure of large mammals has undergone considerable rearrangements. The monitoring of such phenomena is worth of a serious zoological research. The paper discussed methodological issues for such studies with particular attention to techniques of monitoring with aid of automated camera traps. Relations of the recorded faunal changes and landscapes rearrangements during past decades are also discussed. The paper is supplementing with a brief summary of two-year camera trap study in Brdy Mts. Key words: carnivora and ungulates,...
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Genus Neomys (Mammalia, Eulipotyphla, Soricomorpha): history and range dynamics.
Pažitková, Barbora ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
Based on numerous literary sources, the thesis reviews current knowledge of history and range dynamics of the genus Neomys, an indexing element of the west Palearctic mammal fauna. It provides a list of fossil records attributed to the extant genus Neomys and extinct clades composing the European records of tribe Nectogalini, and a survey of hypotheses on their phylogenetic relations. Particular attention is given to the genus Asoriculus which is generally considered as an ancestor of the Quaternary radiation of the clade represented in Europe with genera Nesiotites, Neomys and Macroneomys. The transition from Asoriculus to Neomys is expected to appear during the Q1 stage of the Early Pleistocene, more records identified as fossil species of the latter genus are reported from terminal stage of the Early Pleistocene (Q2). Nevertheless, their relations to extant species were not analysed and past history of the extant European taxa (fodiens, anomalus, milleri) and their range dynamics is despite of molecular data generally unclear. This fact reflects both scarcity of the fossil record and uncertainties regarding patterns of phenotype variation in particular species, their discrimination criteria and orientation of corresponding phylogenetic morphoclines. In these regards, the thesis pays special...
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Western Carpathians as diversity hotspot during the Quaternary climatic cycle
Kubíková, Kateřina ; Juřičková, Lucie (advisor) ; Horáček, Ivan (referee)
In the context of the entire Europe, the Western Carpathians is a unique area of priceless biological significance. Topological complexity, together with significant climatic and edaphic variability, is reflected in the high habitat heterogeneity and has enabled the survival of a large number of species in this area during the Quaternary climatic cycle. The Western Carpathians thus represents one of the most important glacial as well as interglacial refugium in Europe. The result of these environmental variables and the unique history of this region is an enormous species diversity, a high degree of endemism and the occurrence of many glacial relics. This bachelor's thesis contains a review of mainly zoological studies dealing with high biodiversity and degree of endemism in the Western Carpathians and its possible causes. The role of the Western Carpathians as an important Pleistocene refugium, its influence on other parts of Europe and the postglacial development of the area are discussed in individual chapters.
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Sonar design in Old World bats: patterns of specialisation
Staňková, Markéta ; Horáček, Ivan (advisor) ; Lučan, Radek (referee)
Echolocation ranks among key components of adaptive setting of bats. It enabled them to evolve a plethora of diverse foraging strategies and exploit an enormous spectrum of food resources for which they represent one of the most diversified groups of terrestrial mammals with a cosmopolitan distribution. Evolution of echolocation proceeded via responses to diverse constraints and factors, both intrinsic and extrinsic, that effect particular variables of echolocation biology. The present bachelor surveys, based on literary records, briefly some of these effects and their role upon structure of bat communities. I summarize basic characteristics of echolocation types, influence of Doppler shift, strategy and use of echolocation in different environments and adaptation against defensive abilities of a prey. Among other I provide an account of history and evolution of bat detectors, the instruments essentially improving current study of that topics. Keywords: Bats, echolocation, sonar, diversity, adaptation, Old World
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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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Concept of body in Old Norse literature
Novotná, Marie ; Komárek, Stanislav (advisor) ; Horáček, Ivan (referee) ; Starý, Jiří (referee)
This work attempts to outline concepts associated with body in the Old Norse literature. As the word for the body (líkamr) as well as the term for an incorporeal soul (sál) do not occur in the Old Norse literature until the translated Christian works and cannot therefore be used as markers, two areas closely connected with the concept of body have been chosen for the research: shifting of shape (hamr) and somatic expressions of emotions. In the first area, i.e. phenomena associated with shape-shifting, contexts of all (113) occurrences of radix ham- in the Old Norse literature are analysed in order to describe the semantical field of this root. Within the themes that have appeared in the material (i.e. shape-shifting related to flying, battle frenzy and magic), occurrences are ordered on an axis from those where the form (hamr) is considered to be holistic to those where just the form of body or soul is described. In this context, it is important to mention the proximity of man and animal in the Germanic environment, as shape-shifting is often related to an animal and thus points to the limits of human identity. In the second area, i.e. somatic expressions of emotions, we can also find cases where the mental and the physical area intersect and the boundaries between diseases and emotions are not...
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