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Evolution of litter size in hystricomorph rodents
Cingelová, Alexandra ; Dušek, Adam (advisor) ; Špoutil, František (referee)
The suborder Hystricomorpha is an ideal model group for the study of rodent life-history evolution due to its wide distribution, great diversity of inhabited ecosystems and social systems. By tracking several factors, it was possible to determine the key factors that influenced litter size during evolution. The data set contained 75 of the total 292 species of the suborder. The average litter size, female and male body size, level of sexual dimorphism, level of sociality, type of reproductive system, level of parental care, presence of multipaternity, type of habitat and food were assigned to each species based on the information obtained from the available literature. The analysis included a statistical part calculated using general linear mixed models, and a phylogenetic part including parsimonious mapping of characters onto the phylogenetic tree and linear regression using phylogenetic independent contrasts. Social factors like degree of sociality, sexual dimorphism and reproductive system significantly influenced litter size at birth. Multipaternity also had an influence, but less than the first three factors. Ecological factors, food and environment, had no effects unless they were combined with the effect of family. It is therefore possible to assume that ecological factors have influenced...
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The influence of physiologically controlled motor activity on biomechanical cross-section properties of long bones.
Jindrová, Alena ; Sládek, Vladimír (advisor) ; Špoutil, František (referee)
The mechanical loading affects the long bone cross-section geometry (CSG). The aim of this thesis was to examine experimentally the relationship between the locomotory parameters and cross-sectional properties of long bones, and to test some partial knowledge of the bone mechanical adaptation. Two groups of B6CBA mice were examined: (a) Lurcher type (model of olivocerebellar degeneration; n = 10) and (b) control (normal mice; n = 10). We analyzed the motor characteristics and the bone cross-sectional geometric properties. The motor tests included the test of spontaneous motor activity (Open field), strength properties (horizontal bar) and motor coordination (rotarod). Cross-sections were taken in 50 % of the left tibia biomechanical length and further processed for fluorescence confocal microscopy. We analyzed the biomechanical properties of cortical bone cross-sections (software ImageJ). There were nonsignificant differences in CSG parameters (TA, CA, Imax, Imin, J, Imax/Imin) between Lurcher and control mice. The results did not support our assumption about the effect of motor disorder on CSG properties. We did not demonstrate the effect of local factors on the bone biomechanical adaptation. The results of this thesis may be useful to find new testing possibilities of cortical bone in...
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The influence of physiologically controlled motor activity on biomechanical cross-section properties of long bones.
Jindrová, Alena ; Sládek, Vladimír (advisor) ; Špoutil, František (referee)
The mechanical loading affects the long bone cross-section geometry (CSG). The aim of this thesis was to examine experimentally the relationship between the locomotory parameters and cross-sectional properties of long bones, and to test some partial knowledge of the bone mechanical adaptation. Two groups of B6CBA mice were examined: (a) Lurcher type (model of olivocerebellar degeneration; n = 10) and (b) control (normal mice; n = 10). We analyzed the motor characteristics and the bone cross-sectional geometric properties. The motor tests included the test of spontaneous motor activity (Open field), strength properties (horizontal bar) and motor coordination (rotarod). Cross-sections were taken in 50 % of the left tibia biomechanical length and further processed for fluorescence confocal microscopy. We analyzed the biomechanical properties of cortical bone cross-sections (software ImageJ). There were nonsignificant differences in CSG parameters (TA, CA, Imax, Imin, J, Imax/Imin) between Lurcher and control mice. The results did not support our assumption about the effect of motor disorder on CSG properties. We did not demonstrate the effect of local factors on the bone biomechanical adaptation. The results of this thesis may be useful to find new testing possibilities of cortical bone in...
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Microstructure of a tribosphenic molar - comparative analysis
ŠPOUTIL, František
The proposed thesis concerns in the study of tribosphenic molar, the key apomorphy of mammalian clade, mainly in structure and development of its enamel coat. As the main model species served us European vespertilionid bat Myotis myotis. The aims of this thesis are: (1) to describe structure and microstructure of enamel in tribosphenic molars in detail; (2) to compare it with unicuspid teeth of the same dentition; (3) to describe mineralization process and enamel maturation in insectivorous dentition; (4) to describe late odontogenesis in molars of insectivorous dentition and its interlacing with enamel maturation, and how they come to occlusion.
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