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Evolution of vipers and the role of key innovations in their diversification
Waldhauser, Vojtěch ; Šmíd, Jiří (advisor) ; Gvoždík, Václav (referee)
The family Viperidae consists of 36 genera, containing more than 350 species in total. The family is distributed throughout Africa and most of Eurasia, however the greatest diversity is located in North and South America, where more than 40 % of the viper species can be found. The family is thus missing only in Australia, New Guinea, Madagascar, New Zealand and a number of other islands and archipelagos. As with most reptiles, they are also almost completely absent from polar regions, with the exception of Vipera berus, the only snake that has ventured north of the Arctic Circle. Their relative evolutionary success is attributed to many so called "key innovations", which include solenoglyphous dentition, viviparity of many genera or heat- sensing pits in the subfamily Crotalinae. Vipers are not only interesting because of their evolutionary history, but they are also subject of important medical studies regarding their venom and toxicity. WHO estimates that around 100,000 people worldwide may die from snake bites each year. This thesis presents a summary of our current knowledge of the evolutionary history of this family, including phylogeny and biogeography, and contemplates the mechanisms behind its amazing diversity.
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Phenotypic and molecular approaches in the systematics of the Palearctic and Neotropic tree frogs, Hyla and Osteocephalus (Amphibia: Hylidae)
Gvoždík, Václav ; Moravec, Jiří (advisor) ; Mikulíček, Peter (referee) ; Hulva, Pavel (referee)
The systematics and taxonomy of tree frogs of the family Hylidae has undergone turbulent changes both at higher (subfamilies, genera) and lower (species) level during the last decades. The original approach used morphological characters to distinguish tree frogs. It has been completed by bioacoustics, since the advertisement calls of the males were in some cases found to represent an important behavioural reproductive barrier and therefore useful for systematic evaluations. However, a completely new impulse was given to systematics by the introduction of modern genetic methods. These methods have allowed to distinguish not only morphologically but even acoustically cryptic taxa. The most reliable method to distinguish tree frogs at present is a combination of data from the different disciplines. The present dissertation thesis aims to evaluate the systematics of tree frogs of the genus Hyla from Eastern Europe and the Middle East as well as the systematics of the Amazonian genus Osteocephalus using a combination of morphological, bioacoustic and molecular approaches. The thesis is composed of a general introduction, three published papers, two manuscripts under reviews and a conclusion chapter. The first three papers deal with the phenotypic (morphological plus bioacustic) approach in systematic...
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Distribution and invasiveness of Trachemys scripta in the Czech Republic
Brejcha, Jindřich ; Šandera, Martin (advisor) ; Gvoždík, Václav (referee)
Biologické invaze jsou jednou z příčin úbytku biodiverzity na Zemi. Zprávně používaná terminologie je nutností pro objektivní hodnocení výskytu nepůvodních druhů. Nepůvodní druh je taxon zavlečený mimo svůj přirozený areál. Naturalizovaný druh je takový taxon, který se vyrovnal s novým prostředím a vytváři na něm pravidelně se rozmnožující populace, jejichž dlouhodobé přežívání je pravděpodobné. Invazivní je takový naturalizovaný taxon, který se šíří a produkuje potomstvo v oblastech vzdálených od místa vysazení. K vyjádření dopadu na životní prostředí a ekonomiku je vhodné užívat zvláštní kategorie jako jsou škodlivý druh či transformers. Pouze národní bohatství a hustota obyvatel jsou statisticky prokazatelné pro předpovídání invazí napříč všemi taxonomickými skupinami ve srovnaní s klimatem, geografickými faktory a charakterem krajiny. Želva nádherná byla v druhé polovině 20.století zavlečena na pět kontinentů světa. V Evropě je v jižních zemích naturalizovaná až invasivní. Na území České republiky je želva nádherná příležitostný nepůvodní druh (casual species), který se zde pokouší o rozmnožování. První zmínky o výskytu želvy nádherné na našem území pocházejí z 60. let 20. století. Na základě publikovaných údajů, ústních sdělení a nepublikovaných písemných údajů byl sestaven seznam 190 záznamů...
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Body size in reptiles: proximate mechanisms and ecophysiological correlates
Starostová, Zuzana ; Frynta, Daniel (advisor) ; Gvoždík, Václav (referee) ; Sedláček, František (referee)
Body size is a fundamentaltrait determininga suite of morphological, physiological andecologicalcharacteristicsoforganisms.The thesisdealswith topicscloselyrelated to proximate mechanisms of body size change in lizards and with ecophysiological correlates of body size such as metabolic rate and influence of environmental temperature.The Ph.D. thesis contains a brief introductorychapterand four chapters representedby threepublished or acceptedpapersand one submittedmanuscript.All papers included in the thesis have in common that they take into the account phylogeneticrelationshipsamong studiedspeciesand usedifferent methodsto control the effect of phylogeny. The first chaptershows thatevenwithin closely relatedgroup of lizards from the family Eublepharidae(eyelid geckos),thered blood cell size differs considerably and is conelated with body size. The cell size supposedly played an importantrole in evolutionary changesin body size in this group. The secondchapter is focused on evolutionary changes in genome size in eyelid geckos and on the relationship between cell size and genome size. The changes in genome size correspond well with phylogenetic relationships among eublepharids, but are independent on evolutionary changes in cell size. At higher taxonomic levels a positive correlation between genome...
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Genetic variation and contact zone of two species of Slow Worm (Anguis fragilis, A. colchicapublics
Šifrová, Helena ; Gvoždík, Václav (advisor) ; Hulva, Pavel (referee)
The members of the genus Anguis are widely but hidden living reptile species in the Czech and Slovak Republic. Due to their slight morphological characters among species of the genus, presence of two out of five species in the study area has only recently been confirmed. However, a detailed knowledge about their distribution, contact zones or potential hybridization is still unknown or very insufficient. In this master thesis, 407 individuals of Anguis fragilis and A. colchica out of 281 locations were genotyped. 407 sequences of the mitochondrial marker ND2, 170 sequences of PRLR and 156 sequences RAG1 (both nuclear markers) were used for the genetic analyses. The results confirmed the dominant species A. fragilis for the Czech Republic and A. colchica for the Slovak Republic. The contact and potential hybrid zone has north-south direction from northern Moravia and Silesia, across the Morava River valleys to the Little Carpathians and the Danubian Lowland in Slovakia. The most important information of this thesis is about potential hybridization of these species. My analyses reveal that high number of individuals in the north-south direction zone has hybrid genotype. It allowed detecting the width of the hybrid zone and more accurate genetic structure among species and populations. In addition,...
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Spreading of praying mantis (Mantis religiosa) in Europe
Vitáček, Jakub ; Janšta, Petr (advisor) ; Gvoždík, Václav (referee)
Climate change is one of the most important factor determining species ranges. In Europe there is now evidence for northward areal expansion in many Mediterranean insects including the praying mantis (Mantis religiosa). This species is the only representative of the order Mantodea inhabiting central Europe. The northern edge of the species distribution currently reaches latitude 53ř North. Although, the praying mantis is well known insect there is not enough evidence about its phylogeography. In this work three mitochondrial genes (COI, COII, Cyt b) were selected for phylogenetic study. Results indicate three statistically supported distinct lineages in Europe: Eastern European, Central European and Western European. Presumably these lineages are consistent with isolation during the last glacial and re-colonization from glacial refugia. Reduced haplotype diversity on the northern edge suggests currently established populations at the northern distribution border. To validate mtDNA results it was also considered four microsatellite loci. Due to different type of inheritance mtDNA and nuclear DNA it is possible to compare two independent genetic datasets. Microsatellite analysis confirmed results obtained on mitochondrial data. Three major genetic clusters were found: east, west and central. Spatial...
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Phylogeny of selected genera of geckos in the Mediterranean and adjacent regions
Červenka, Jan ; Kratochvíl, Lukáš (advisor) ; Moravec, Jiří (referee) ; Gvoždík, Václav (referee)
Phylogeny of selected genera of geckos in the Mediterranean and adjacent regions Jan Červenka Ph.D. thesis Abstract This Ph.D. thesis is composed of three published articles and one manuscript, and is focused on the phylogenetic relationships of selected species of geckos from the Mediterranean and surrounding areas. The group of geckos of interest shares the common characteristic of an absence of adhesive lamellas on their toes. Historically, it was assumed that these species were closely related. Molecular-phylogenetic approaches were used in order to reveal the phylogenetic relationships within this group, especially using the sequential data from mitochondrial genes. Morphological characteristics commonly used in lizards were studied in connection with the ecology of the group. This thesis provides the first more detailed view of the phylogeny of the studied species. The results show that the genus Cyrtopodion, previously considered as monophyletic, in fact is not monophyletic as the genera Bunopus and Agamura represent its inner groups. Mediodactylus, the subgenus of Cyrtopodion, forms monophylum but is not closely related to the other members of the genus and so was reclassified as the independent genus. The enigmatic and yet so far very poorly studied genus Carinatogecko was discovered to be the...
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