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Spatial orientation in reptiles focused on methods of testing of allothetic navigation
Voňavková, Monika ; Landová, Eva (advisor) ; Telenský, Petr (referee)
Recently are known several different navigational systems in reptiles, mainly large scale navigational abilities based on sun and magnetic compass. The turtles are frequently used species in studies of spatial cognition, however, informations about spatial cognitive abilities in snakes and lizards (order Squamata) are only a few. Current knowledge concerning mechanism of small scale navigation based on allothetic orientation in snakes and lizards is only poorly understood. Aim of this thesis is review the literature about the mechanisms of reptile spatial orientation focused on allothetic navigation (using of external landmarks). As extension of this thesis is review of the principles of testing allothetic orientation in other groups (e. g. mammals) that were frequently used as a subject for testing allothetic orientation). The design of tests of allothetic orientation in model species of lizards (Eublepharis macularius) is one of the results of this thesis. Keywords: reptiles, spatial orientation, allothetic navigation
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Parthenogenetic lizards of the genus Darevskia as an evolutionary model
Abramjan, Andran ; Frynta, Daniel (advisor) ; Janko, Karel (referee)
Several parthenogenetic lineages occur within the lizards of the genus Darevskia (Sauria: Lacertidae) which are endemic to southern Transcaucasus. High level of heterozygosity, cause by thein hybrid origin, is one of the crucial aspects of thein evolutionary potential, as well as the asexual reproduction. Heterosis on one side is in the opposition to the outbreeding depression and genetic uniformity of the clones on the other side. Aim of this work is to evaluace if these aspects influence viability of parthenogenetic species and differ them from the sexual ones. We chose the amount of asymmetries as a measure of developmental instability, which we studied on three meristic characters. We also evaluated the pattern of asymmetries in lateral blue spots, which are of signaling importace in lacertid lizards. Our results suggest that there isn't significant difference between parthenogenetic and sexual species in developmental stability, but the sexual ones are more sensitive to population changes. Absence of males may have perhaps the greatest influence on coloration, resulting in loss of symmetry in the blue spots.
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Noninvasive measurement of steroid homones and effect of hormonal manipulation on behaviour in the gecko Paroedura picta
Matušková, Lucie ; Kratochvíl, Lukáš (advisor) ; Fraňková, Marcela (referee)
Hormones influence life of all animals. Not only they affect physiological changes in organisms, but also impact their behaviour. This work focuses at two main groups of steroid hormones: glucocorticoids and androgens. Glucocortiods are activated in response to stress. Their levels can be measured using non-invasive methods, which have a range of advantages. The main advantage is the feedback-free sample collection for enzyme immunoassay. As the measurement involves metabolites of the hormones rather than the hormones themselves, prior validation of the method is, however, necessary. This work reports on a study aiming to validate non-invasive measurement on the Madagascar Ground Gecko (Paroedura Picta). The validation was based on ACTH challenge test: Synacthen Depot was injected, which should lead to increased blood level of glucocorticoids. The validation, however, was not successful. The measurement did not discover significant increase in the levels of the metabolites of glucocorticoids. In addition, the work focuses on behavioural effects of testosterone, the primary androgen. Hormonal manipulations have been carried out on several male and female specimens. The results have discovered differences in sexual behaviour between control groups. On the other hand, the hormonal manipulations had no...
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Evolution of sex-determining mechanisms and genomes in squamate reptiles (Reptilia: Squamata)
Pokorná, Martina ; Kratochvíl, Lukáš (advisor) ; Marec, František (referee) ; Vyskot, Boris (referee)
Evolution of sex determining mechanisms in squamate reptiles (Reptilia: Squamata) Martina Pokorná Ph.D. thesis Abstract This Ph.D. thesis is focused on the evolution of sex determining mechanisms and genomes in squamate reptiles. It is based on three published articles and two manuscripts. The evolution of sex determining mechanisms, sex chromosomes and genomes, and their organisation, was studied on a wide phylogenetic scale of the whole group of squamate reptiles and some lineages of other Sauropsids, as well as on the small phylogenetic range as a detailed comparative study inside individual lineages of squamates. This thesis is based upon the use of classical cytogenetic methods, methods of molecular cytogenetic (especially fluorescent in situ hybridisation) and the results were analysed using phylogenetic approaches. The results and outputs of this study represent an important contribution to the general knowledge of the principals of sex determination and the evolution of these phenomena not only in squamate reptiles but also in the whole group of amniotes. Using the results obtained during the work on this thesis we can conclude that sex chromosomes evolved in particular lineages of amniotes independently. This origin was in some cases followed by accumulation of microsatellite sequences on sex...
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Evolutionary contraints in the origin of viviparity in Amniotes Why there are no viviparous birds?
Chmelová, Kristýna ; Kratochvíl, Lukáš (advisor) ; Gvoždík, Václav (referee)
Evolution of life-bearing have fascinated biologists for over a long time. Viviparity has evolved many times within separate vertebrate lineages and it is a geographically widespread phenomenon. The majority of these independent origins have occured within lizards and snakes. Several hypotheses have been suggested to explain the selective pressures leading to viviparity in reptiles. One of the most frequently supported hypotheses views viviparity as an adaptation to a cold climate, i.e. viviparous mothers ensure favorable thermoregulation to developing embryos. It is generally supposed that egg retention is an intermediate stage in the evolution of live-bearing. Inclination to egg retention seems to be one of the most important preadaptations of viviparity in vertebrates. Additional limiting factors are probably for instance type of eggshell, mode of sex determinantion or egg guarding as an alternative mode of parental care.
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Cryptids
Dvořáková, Dana ; Turek, Filip (referee) ; Sterec, Pavel (advisor)
Cryptids, video which is studying animals, its shapes, moves and the environment , where they find themselves. The video is looking equal to all entity without any difference, document varied life as same as passing death or rot as well. It also speaks about collaboration and the microworld, which creates perfect unit. Silent mutual conversations.
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Exotic species of herpetofauna in Europe and their impacts on native species
VOREL, Michal
The aim of this study was to carry out a research about the invasions of alien species of herpetofauna and their impacts, to present contemporary state of the studies of alien species in Europe, to analyze success of the invasions in terms of their taxonomic groups, to analyze the impacts of successful inavasions, to evaluate the results and suggest the project of appropriate precausions. Database Web of Science, Zoological Records and web browser Google Scholar were used as sources for searching scientific papers. These were the key words: "alien, reptiles/reptilia; alien, amphibians/ambhibia, invasive". The scientific studies which mentioned introduction of alien reptiles and amphibians to Europe were chosen from database. Population which was viable and reproduced repeatedly was considered as the stable population. Eight species from order salamanders, 20 frogs, eight turtles, 23 lizards and 11 snakes were introduced into geografic part of Europe. The most of the introduced species of alien herpetofauna belonged into families: Ranidae, Lacertidae and Emydidae. The most common pathways for introduction of alien species of herpetofauna were: pet trade, intentional release and cargo stowaway. In the future, the restriction of breeding certain problematic species (ban of import Lithobates catesbeianus and Trachemys scripta scripta into the Europe), more thorough controls of cargo transportation and especially information campaign in schools and media could be solution to the issue of introduction of alien species.
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Population dynamic of amphibians and reptiles of Vlkovská sandpit
RŮŽIČKA, Jan
The theoretical part contains summary of the literature on the topic of succession, mining, human impacts on biodiversity, land reclamation and ecological requirements of reptiles and amphibians. The practical part contains the observations of these two model groups of animals and subsequent evaluation of their abundance and diversity. During the three years I made total 37 herpetological observation, during which I observed the occurrence of eight species of reptiles and amphibians on five locations. When observing reptiles and amphibians I used non-invasive methods of observation. The found species were Zootoca vivipara (507 individuals), Lacerta agilis (583 individuals), Pelophylax esculentus (976 individuals), Pelophylax ridibundus (710 individuals), Pelophylax lessonae (1,401 individuals), Lissotriton vulgaris (203 individuals), Natrix natrix (32 individuals) and Anguis fragilis (7 individuals). The values in the brackets represent the total number of individuals found during 3 seasons. Generically the richest site was "Jezírka" (8 species), species habitat poorest contrary, "Přesyp" (2 species). In all the years the abundance of two model groups (frogs and lizards) were significantly different (abundance of Pelophylax: Chí Square = 2764; d. f. = 4, p <0.001, Zootoca + Lacerta: Chí Square = 119; d. f. = 4, p <0.001. Pelophylax: Chí Square = 1573; d. f. = 4, p <0.001, Zootoca + Lacerta: Chí Square = 43; d. f. = 4, p <0.001. Pelophylax: Chí Square = 37; d. f. = 4, p <0.001, Zootoca + Lacerta: Chí Square = 741; d. f. = 4; p <0.001). The researchl lasted three vegetation seasons. They had distinctly different climatic conditions. The abundance of reptiles and amphibians in season of 2013 was significantly impacted by the spring floods. Season 2014 any major climatic fluctuations and therefore I considered it as a standard. Season 2015 was greatly influenced by the high summer temperatures and the lack of greater precipitation during the summer months. This fact influenced mainly amphibian populations.
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Non-invasive methods for individual identification of reptiles
KROUFKOVÁ, Michaela
Reptiles are a common group of animals used to various researches. Invasive identification methods are often used in these researches to recognize individuals in population. These methods negativly affect lifes of individuals and can cause die-off. For these reasons so called individual non-invasive identification methods arise, which can help with better handling of examined individuals and their easy and cheap recognition. These are easy and fast methods, where morphological characteristics of individuals and their natural unusualnesses of their body signs (scars, spots) are used. Very importand method is photografical identification with help of photografical system called I3S (Interactive Individual Identification System), which uses significant lizards signs very similar to peoples fingerprints. In this work you can find a review of studies which are concerned with these non-invasive methods. These methos can improve identification of individual reptiles and hadling with them. Above all, this work contains reptile species, where these methods are succesfully used and a summary of morphological characteristics by which the identification is performed.
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Effect of disturbances on reptile and amphibian assemblages in oak forests of Podyji National Park
BALOUN, Jaroslav
The thesis focuses on the monitoring of reptiles and amphibians of different habitats in six sampling areas in the Podyjí National Park. The monitoring was conducted by the method visually searching for reptiles along walking transect and by using black pond foils as artificial hiding places from 2012 to 2015. The thesis evaluates habitat preferences of reptile species common in the area. The most preferred were partially open habitats, such as the forest edge and open sparse oak forest. The least preferred habitat was shady, closed-canopy forest. The results demonstrate the positive effect of distrubances on most reptile species in the oak forests of Podyjí NP. Habitats suitable for numerous endangered species, including many reptiles, decline due to gradual overgrowing of sparse oak forests and woodlands. The results of this thesis highlight the importance of active conservation forest management to protect the presence of open woodlands and sparse forests.
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