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An ecological perspective on diatom morphology.
Fialová, Markéta ; Kulichová, Jana (advisor) ; Hodač, Ladislav (referee)
A traditional species concept of diatoms is based on morphological characters of their siliceous boxes. A multidisciplinary approach to defining species of diatoms has revealed the hidden diversity within the traditionally defined species. But the newly recognized species are morphological variable and indistinguishable by the naked eye. Recent studies showed that different morphotypes show different ecological preferences. This master thesis focuses on the morphology of natural populations of the diatom species complex Frustulia rhomboides which contains both the traditional and the cryptic species, and it engages how the morphology reflects the effects of environmental conditions. Landmark methods of geometric morphometrics were used in order to analyze the morphological variability of diatom frustules of this species complex within various peat bog habitats in the Czech Republic. Selected environmental parameters were measured and the species composition of diatom communities present in the samples was investigated. These data were used to analyze the relationship between the environmental conditions and the cell shape variability within the complex. The analysis revealed the main trends of morphological variability related to different environmental conditions. Two morphotypes characteristic...
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Influence of environmental variables on the shape of ultraviolet pattern in Gonepteryx rhamni
Pecháček, Pavel ; Kleisner, Karel (advisor) ; Hořák, David (referee)
Many species are sensitive to a light in ultraviolet spectrum. Some species have surface patterns that reflect ultraviolet light. These markings have been observed in many animal taxa; butterflies (Lepidoptera) are no exception. UV-reflectance in butterflies has been primarily connected to sexual selection and in this respect it has been a subject of many studies. In my work I propose an alternative view to this phenomenon. The aim of my work is to reveal how a particular environmental factors influence the morphospace of UV- reflectant patterns and wing shape of the Gonepteryx rhamni (Pieridae). The effect of various environmental factors (latitude, longitude, altitude, mean annual temperature, mean annual precipitation, normalized difference vegetation index - NDVI or net primary productivity - NPP) on wing morphospace was tested using the methods of Geometric morphometrics. I have also studied shape variability among the males and females, specimens from different locations and differences in morphospace of several G. rhamni subspecies. The dataset used in this analysis includes 118 males and 67 females from the Palearctic ecozone. The effect of almost all environmental (except to NDVI and NPP) predictors on shape of the UV-pattern and wing margin was significant in the case of males. In the...
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Ontogeny of Sao hirsuta (Barrande, 1846) in the Cambrian of Czech Republic: revision
Laibl, Lukáš ; Fatka, Oldřich (advisor) ; Kleisner, Karel (referee)
The Solenopleurid trilobite Sao hirsuta Barrande, 1846 is known from "Middle" Cambrian sedimentary rocks of the Czech Republic, Germany and Spain. It is one of the first trilobites on which ontogenetic development was described in detail (Barrande, 1852). This diploma thesis is the first modern revision of the ontogeny of this species for more than fifty years. Thesis is primarily based on quantitative methods and a detailed study of morphology of the exoskeleton. Changes in the dorsal exoskeleton during ontogenetic development of S. hirsuta, including the discovery of intrainstar morphological and size variability and the transition from isometric growth to the alometric growth, were described in detail by using quantitative methods (biometric measurements and geometric morphometrics). In the protaspid period different instars of S. hirsuta were recognized. Detailed morphological studies revealed several different morphotypes of protaspid stages. Some of which may represent different taxa. The morphology and the condition of the hypostome was described, including changes of hypostome during ontogeny. The study of segmentation in the species S. hirsuta shows hypoprotomeric development with the initial accumulation phase, middle equilibrium phase and terminal depletion phases. Key words: Sao...
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Geometric morphometrics of diatom frustules.
Hubáčková, Kateřina ; Kulichová, Jana (advisor) ; Pichrtová, Martina (referee)
This bachelor thesis includes a theoretical and a practical part. In the theoretical part, I focused problematic parts of research of diatoms biology. I will discuss morphology of specific silica scale and its morphogenesis; life cycle, characteristic by the size diminution in vegetative phasis, and conception of taxonomy of these organisms which is rather complicated because of unclear species concept. Another part presents tools of geometric morphometrics which is rapidly developing method for investigation and quantification of biological shape. In the practical part, I present the results from own research. This experiment is preliminary study for diploma thesis and its purpose is to appropriate tools of geometric morphometrics and to present advantages of its methods. I will investigate morphological disparity of three strains of pennate diatoms cultivated in standard conditions studied by landmark methos. The aim of this study is to discover if small cells which have gone trough the long phasis of vegetative multiplication and are close to the sexual reproduction have diferent degree of morphological variability than the bigger ones just undergone by sexual process.
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Using classic versus geometric morphometrics in anthropology
Pinkr, Tomáš ; Velemínská, Jana (advisor) ; Brůžek, Jaroslav (referee)
Shape differences and their analysis may reveal differences in the growth and morphogenesis, the influence of different evolutionary pressures, or the consequences of a disproportionate burden of the various parts of the body. Variability of some characters cannot be measured, but it can be observed and described verbally, or eventually described in photographs or schematically. A morphoscopy deals with it and currently beside the traditional direct visual observations also modern technology is utilized. Morphometry unlike morphoscopy is used for measurement and comparison of organism shapes and shape changes analysis. Outputs of morphometric examination are tables of numbers and mathematical and statistical operations are used to obtain information from these data. Current anthropology divides morphometry to two slightly different sets of methods a traditional morphometrics and a geometric morphometrics. The traditional morphometrics measures directly object of study using conventional measuring tools. Conversely, the geometric morphometrics analyzes object in the virtual space using sopfisticated instrumentation including special software. Display methods store information about geometry of the subject. Resulting databases are used not only for the original analysis but also for other research as...
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Evaluation of ontogenetic development of the mandible using geometric morphometric methods
Kiebelová, Alena ; Velemínská, Jana (advisor) ; Brůžek, Jaroslav (referee)
During ontogeny there are a lot of changes in the entire human skeleton. This thesis deals with shape changes in the mandible, which are caused by genetic, hormonal, as well as mechanical factors. The most important mechanical factors influencing the shape of mandible are development of deciduous and permanent dentition and also development of masticatory muscles. 34 children mandibles of known age and 14 adult mandibles were analysed and compared for this thesis. Data were obtained by scanning coordinates of 36 landmarks using Microscribe G2X, and then were processed by software PAST and Morphologika2 using multivariate statistics (PCA, MANOVA). Geometric morphometrics is used for a detailed analysis of shape changes of the mandible. There is no difference between dental and chronological age. In conclusion, lower jaw narrows during growth, the body extends more in the region of third molars and the ramus grows mainly in the region of condylar process. Chin prominence also occurs during ontogeny. In the group of adult mandibles the variability is caused by coronoid process height and the body width. The hypothesis, that age groups are significantly different from each other, and therefore due to tooth mineralization there are marked shape changes, is confirmed.
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Ontogenetic changes of the face.
Benešová, Eliška ; Eliášová, Hana (advisor) ; Dvořák, Daniel (referee)
The human face is characterized by a combination of morphological characters, which are unique for each individual. These characters are subject to change during ontogeny influenced by age, pathological conditions, injuries. The aim of this diploma thesis was an observation of age changes in the face of individuals in the age range from one to eighteen. Resource material were black and white photographs of girls and boys. Analysis of age changes in facial area was performed using methods of geometric morphometrics, specifically thin plate spine (TPS). The shape analysis confirmed, that between age and face shape exists significant relationship. It was found, that is mainly due to significant changes in height and width ratios. Face extends and narrows, forehead height is reduced and lower jaw grows to lenght. Facial changes are also influenced by the sex of individuals, while for girls the overall growth in the face stopps about age of fifteen, for boys continues to the age of eighteen years. Keywords Geometric morphometrics, thin plate spline, ontogenetic development of the face, age changes.
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Population and geographic variation in long-winged bats (Miniopterus) in the western Palaearctic
Šrámek, Jan ; Benda, Petr (advisor) ; Hanák, Vladimír (referee)
In this study the sexual and geographical variations in the genus Miniopterus were deeply investigated, using multidisciplinary analysis (morphometric cranial, dental, fenetic and shape analysis; molecular analysis of mt gene ND2). Different populations from western Palearctic and adjacent regions were analysed: Miniopterus schreibersii (Morocco, West Europe, Pannonia, Balkans, Crete, Near East, Middle East), Miniopterus natalensis (Yemen, Ethiopia) a Miniopterus inflatus (Ethiopia). Extensove samples of Miniopterus schreibersii were tested and existence of sexual dimorphism in cranial constitution was showed: males had generally bigger and relatively higher, shorter and narrower skulls than females; female mandibles were generally bigger than the male ones, females showed also more robust and larger teeth than males. On the other hand, males had markedly bigger canines and relatively higher P4 (in relation to other premolares). The sexes also deiffered in shape of P4 and upper molars. According to the interpopulation variation found, Miniopterus schreibersii samples from West Europe, Pannonia, Balkans, Crete, Sicily, Georgia, coastal Turkish and Moroccan areas belong most probably to the subspecies M. s. schreibersii (Kuhl, 1817). The samples from Afganistan, Iran, Azerbaijan, and from localities...
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Forensic Identification of Child Faces
Klíma, Ondřej ; Španěl, Michal (referee) ; Beran, Vítězslav (advisor)
This thesis is focussed on children's faces comparison. Its aim is to create the application providing functions for photocomparison and ageing. Both these parts work with portrait photos of children. Photocomparison purpose is a metric expression of similarity of two portraits independently on their age. Ageing is a tool for the simulation of an individual's growing old on the photo. Principles of both functions are based on geometric morphometry methods, particulary on procrustes analysis and thin-plate spline aproximation.
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Variation in the \kur{Melampyrum sylvaticum} group
TĚŠITEL, Jakub
This study deals with morphological variation in the Melampyrum sylvaticum group (Orobanchaceae). Populations of the Hercynian Massif, Western and Eastern Carpathians were investigated using both conventional and geometric morphometric methods. Individual morphological characters were evaluated in detail. Preliminary taxonomic concept of the group is presented. Biogeographical context of detected morphological variation is discussed.
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