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Dental phenotype variation in voles during the present glacial cycle
Putalová, Tereza ; Horáček, Ivan (advisor) ; Kuneš, Petr (referee)
The phenotype dynamics of arvicolid rodents during the terminal stages of the Vistualian glacial and the earliest Holocene was investigated with aid of a detailed morphometric analyses of extensive dental material from three sedimentary series of that age. The particular attention was paid to the record from a section in Býčí skála cave, Moravian karst, which demonstrated details of the Pleistocene/Holocene transition (12.4-8.4 ky BP) with extraordinary resolution. It revealed that dramatic rearrangements in community structure were accompanied by significant rearrangements of the phenotype dynamics in all arvicolid species. Despite some trends specific for particular species, some common features were identified as well. One of them was a rapid turnover in phenotype structure by the end of Younger Dryas, at time of the Preboreal event. (11.7-11 ky BP), the other was associated with the extensive shifts in community structure and habitat diversity at terminal stage of the Preboreal (9.7-9.3 ky). The core arvicolid species of Preboreal communities, Clethrionomys glareolus, Microtus arvalis, M.agrestis and Arvicola terrestris, exhibited repeated fluctuations during that stage (ll-9,3 ky BP) both in abundance and phenotype characteristics, supposedly related to serial invasion events during that time....
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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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Enamel micromorphology of the tribosphenic molar
Hanousková, Pavla ; Horáček, Ivan (advisor) ; Robovský, Jan (referee)
The tribosphenic molar is an ancestral type of mammalian teeth and a phy- lotypic stage of the mammalian dental evolution. Yet, in contrast to derived teeth types, its enamel microarchitecture attracted only little attention and the information on that subject is often restricted to statements suggesting a simple homogenous arrangement of a primitive radial prismatic enamel. The present paper tests this prediction with aid of comparative study of eight model species representing the orders Chiroptera, Afrosoricida, Eulipotyphla (Erinaceomorpha) and Eulipotyphla (Soricomorpha). Spe- cial attention was paid to shrews (Soricidae), the group with most derived tribosphenic dentition among extant insectivores. The detailed electron microscopic (SEM) analysis of standardized cross sections over essential structural elements of tribosphenic molars (in shrews supplemented with sections of the lower incisor, the most derived tooth of the dentition) was a basic source of information. The results demonstrated common arrangements related to tribosphenic design (he- terotopy of enamel thickness, radial prismatic enamels as primary product of ameloge- netic activity), yet, an unexpectedly broad span of variation in state of further variables was discovered at the same time. The taxon-specific arrangements and...
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Archeozoology of the Unetice culture in the light of divergent approaches
Trojánková, Olga ; Horáček, Ivan (advisor) ; Kovačiková, Lenka (referee)
This work summarizes results of a comprehensive analyses of the archaeozoological material on the settlement in Vlíněves dating to the Unetice culture (the early Bronze Age, Central Bohemia). The total of 5325 bones and teeth has been analysed within this analysis, 903 of them was determined and used for further analyses. The taxonomic structure of the material with a clear prevalence of domestic mammals was assessed, the proportion of other groups was low (7 species of wild animals). The application of stable isotopes and dental microwear analyses of faunal assemblage, first used in Bohemia in the context of the Bronze Age period, has specified the nature of a dietary base livestock as grassland habitats, and has ruled out a significant ratio of C4 plants and an application of forest pasture. The combined use of domestic animals with an increase emphasis on so-called secondary products (milk and wool) prove a bimodality in kill-off patterns of sheep and goats, height at withers of sheep, which corresponds to the breeds of sheep extended during the bronze age period and to the high mortality profile of cattle. The proposed results of our work are important in this context because they suggest these facts for the early Bronze Age already. In accordance with circumstances at other sits of Unetice...
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Systematics of the emballonurid bats (Emballonuridae) of the Old World
Uvizl, Marek ; Benda, Petr (advisor) ; Horáček, Ivan (referee)
The family Emballonuridae is one of 18 families of the order Chiroptera and is characterized by a slender tail, which perforates the interfemoral membrane on its dorsal side and in the half of its lenght. Another important character is an absence of the phalangi on the second digit of the hand (wing), where remains only a well-developed metacarpal. Some species are also characterized by a radio-metacarpal pouch and a gular sac, both associated with a gland. Representatives of this family are distributed around the world in the circum-equatorial band of areas. The family is divided to two subfamilies, Taphozoinae and Emballonurinae. Together, these subfamilies contain 14 genera and 49 species. In accordance with their geographic distribution, subfamily Emballonurinae is divided to two tribes, Emballonurini and Diclidurini. Representatives of the tribe Diclidurini occur solely in the New World, while the bats of the tribe Emballonurini live only in the Old World. In the latter region, there could also be found represenatives of the subfamily Taphozoinae that includes two genera, Taphozous and Saccolaimus. The tribe Emballonurini includes four genera: Coleura, Emballonura, Mosia, and Paremballonura and the remaining eight genera of the subfamily belong to the tribe Diclidurini. In the Palaearctic region only...
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Social applications of myrmecology between Aldrovandi and Wilson
Hampl, Petr ; Komárek, Stanislav (advisor) ; Horáček, Ivan (referee) ; Bezděčková, Klára (referee)
The following dissertation presents the history of myrmecology from the times of Ulisse Aldrovandi up to the works of Edward O. Wilson in the 20th century. The oldest mentions of ants in the Antiquity and the Middle Ages are also partially elaborated upon. A special emphasis is given to the general idea about ants as developed by each of the authors, as well as to the mapping out of the contemporary ideas about social insect. This work points out that the portrait of the ant has always been related to the contemporary conception of human society and humanity as such. Throughout its history, myrmecology has always been strongly influenced by anthropomorphism, as the picture of the ant would be derived from the social order, political system and the general opinion on what constitutes human nature. On the other hand, though, myrmecology has also helped to shape the picture of humanity, because the conclusions drawn from myrmecological studies were applied to humans. Therefore, entomology started to influence anthropology and vice versa. In the Antiquity, ants were viewed basically as farmers; only harvester ants were known, they were seen as working on a field, going to the marketplace or holding celebratory festivals. The medieval picture of the ant drew heavily on the Antiquity ideas, but it added...
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The ecological and ethological significance of felid coat patterns (Felidae)
Jaroš, Filip ; Komárek, Stanislav (advisor) ; Horáček, Ivan (referee) ; Weber, Andreas (referee)
The presented work investigates various theories about the significance of felid coat patterns. Most of the hypotheses are based on the theory of adaptive function of animal colouration. As regards felids, it is generally believed that the coat pattern has the function of aggressive resemblance. Early testimonies about cryptic properties of colouration of cats are summarized to provide the historical perspective of the problem. Other putative adaptive functions of patterns are investigated (intraspecific communication, thermoregulation) and close attention is paid to the option that the spotted coat of the leopard (Panthera pardus) serves as a cue for recognition from the perspective of prey. In the next stage, some of the hypotheses are tested by statistical means. The problem is simplified into search for association between a given category of a coat pattern (e.g. spots, stripes) and usual habitat of felid species (e.g. forest, grassland). Pagel's test for correlated changes is employed to account for phylogenetic relationships. In addition to broadly acknowledged hypotheses, the validity of proposition that juvenile coat patterns have the function of protective resemblance is tested. Finally, the problem of colouration of felids is linked to broader context of theoretical biology. Apart from prevailing...
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Abundance trends and range dynamics in European bats.
Žabková, Klára ; Horáček, Ivan (advisor) ; Lučan, Radek (referee)
Bachelor thesis sumarizes available data about bat abundance in middle Europe, especially in the Czech republic. Populations of bats are usually dynamic, which is given by their high sensitivity to environmental changes. Many of these changes are man made, for instance landscape management, agricultural intensification or disturbing bats during hibernation. Impact of global warming on bat abundance and range distribution is also discussed, because it could explain the occurance of mediterranean species Hypsugo savii in Moravia In my thesis, I focus on possible causes of strong population decrease of Rhinolophus hipposideros in 70's in the middle Europe, which led to establishement of monitoring programms accross Europe. Project "Monitoring bats in underground hibernacula" has started in Czechoslovakia in 1969, and it has provided valuable and relevant data. I also compare methods for monitoring bats, because there isn't any effective universal method for censusing all species under all circumstances, due to their specific behavioral habits. Counting bats in underground hibernacula appears to be the most efficient, especially for species such as Rhinolophus hipposideros, Myotis myotis and Plecotus spp. Statistic methods are used to estimate colony size, Lincoln-Peterson method seems to be the most suitable...
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Phylogeny of the genus Helix (Mollusca: Gastropoda: Helicidae)
Korábek, Ondřej ; Juřičková, Lucie (advisor) ; Horáček, Ivan (referee)
The land snail genus Helix comprises large gastropods distributed in from France to Iran and in North Africa. Some of them have close linkage to humans - are synanthropic or are collected and consumed. The genus is most diverse in eastern Mediterranean. Taxonomy of the genus is now being revised from morphological point of view, and a molecular study is needed as a counterpart to that study. Here I present first phylogenetic data for the genus Helix, including almost all currently recognised species. I have used samples from various sources including dried bodies and tissue remnants. I have sequenced two commonly used mitochondrial markers (16S, COI). Position of the genus within Helicidae cannot be inferred from the dataset. The genus should be delimited in a strict sense, excluding genera Maltzanella, Cantareus, Cryptomphalus and Lindholmia. Division into subgenera, as proposed by various authors until now, is not supported with the exception of a split between subgenera Pelasga and the nominotypical Helix. Relationships between species and their groups are poorly resolved. Regarding species limits, the data are largely in agreement with new opinions based on morphology. There might be surprisingly high variability in shell characters within a species, as few morphologically characteristic taxa seem to be...
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