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Technological phase substructure - Business center in Ostrava
Toman, Jan ; Štěrba, Martin (referee) ; Henková, Svatava (advisor)
Subject of this thesis is the lower gross production technology mall in Ostrava. This work contains exactly technical reports, technological specification, site equipment, mechanical assembly design, scheduling, budgeting, monitoring and test plans, safety and environmental protection.
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Storage and dispatch hall including the reconstruction - building-technology project
Toman, Jan ; Štěrba, Martin (referee) ; Henková, Svatava (advisor)
Subject of this thesis is construction technology project storage and dispatch hall in Třebíč. This thesis contains technical report, construction site equipment project, time and financial plan, bill of quantities, technology study of the major technology stages, mechanical assembly design, technological specification, quality inspections.
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Speculative Evolution: Anatomical and Physiological Specifics of Organisms Inhabiting Super-Earths
Šefrna, Radek ; Toman, Jan (advisor) ; Petrásek, Tomáš (referee)
This thesis focuses on super-Earth-like planets, specifically addressing how a larger radius and gravitational attraction, sometimes associated with increased atmospheric density, could affect the direction of anagenesis if other parameters are kept at the terrestrial level. Firstly, super- Earth characteristics are described. Secondly, locomotion and its anatomical and physiological correlates are examined. It concludes that organisms living on the surface would have robust body structure and expects prevalence of the biosphere to exist in the air column on super- Earths with dense atmosphere with organisms resembling ocean life on Earth. Lastly, the thesis investigates life strategies and their potential dependencies on gravitational and surface characteristics, with an emphasis on energy acquisition methods, metabolism, and dispersion. With the existence of complex ecosystem reliant on photosynthesis, existence of ecological niches similar to the ones found on Earth is expected. That could lead to the genesis of symbioses, as they seem to be a universal feature of any biosphere. Due to its speculative nature, the thesis draws conclusions from studies on terrestrial organisms and their environment. It adheres to the phenomenon of convergent evolution to find possible analogies and show potential...
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Relationship between the age of freshwater pearl mussel and the number of increments in shell section
TOMAN, Jan
The aim of this thesis was to determine the relationship between the age of dead individuals of the freshwater pearl mussel (Margaritifera margaritifera) and the number of incremental lines on the shell section. A total of 124 pearl mussel shells of known age were collected from several Czech, German and Finnish localities. There was a statistically significant difference between the actual age and the age according to the number of incremental lines on shell section. On average, the age determined by increment lines was higher than the actual age by 2.6 years, which is 42 ? 25% (? S.D.). Thus, the increment lines on the section of the pearl mussel shell do not correspond to the annual increments. It was confirmed that increment lines count on the shell surface or estimating age from shell size are less reliable approaches to determine the true age of individuals.
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Cambarellinae: Trpaslíci ve světě račích spermií?
TOMAN, Jan
Recently, the ultrastructure of crayfish spermatozoa has become an increasingly studied topic. Up to now, the ultrastructure has been studied and defined in about fifteen species of freshwater species from all four crayfish families, however it has not yet been studied in a group of dwarf crayfish (subfamily Cambarellinae). Present work aimed to describe the spermatozoa ultrastructure of two dwarf crayfish species, specifically the Orange dwarf crayfish Cambarellus patzcuarensis and the Texas dwarf crayfish C. texanus. These species were then compared with the species already studied using morphological traits and biometric data. The ultrastructure of their spermatozoa shows commonly known patterns that include the acrosome and subacrosome in the front and the nucleus on the opposite side of the cell . Furthermore, radial arms typical for the superfamily Astacoidea that wrap around the nucleus and the whole cell enclosed by the extracellular capsule. The results show that the size of the acrosomes of Parastacidae membres is the smallest, while the crayfish of the Astacidae family show the largest acrosome. The current study points out a medium-sized acrosome of dwarf crayfish and Cambaridae in general, although they are located at the lower margin of this family with the Brazos crayfish being close to representatives of the Parastacidae. In conclusion, it is important to say that the combination of the morphological traits and biometric data of sperm acrosomes allows distinguishing individual crayfish groups to a large extent. This study may help to identify other species that have not been studied so far and could be a valuable basis for subsequent research of the ultrastructure and biometrics of crayfish spermatozoa.
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The role of ecological factors in maintenance of sexuality
Toman, Jan ; Flegr, Jaroslav (advisor) ; Janko, Karel (referee)
The existence and widespread distribution of sexual reproduction despite its obvious disadvantages is an evolutionary enigma. According to the theory of frozen plasticity, the evolution of sexual and asexual species is fundamentally different. One of the implications of this theory are different ecological preferences of these species. Sexual species should prefer biotically and abiotically variable environments because of their ability to quickly and reversibly respond to unpredictable changes. On the other hand, asexual species should prosper in biotically and abiotically stable environments because of their ability to perfectly adapt even to extreme environmental factors in the long term. I decided to test these predictions in the metastudy comparing ancient asexual clades (in which we can be sure about their obligate asexuality and evolutionary longevity) with their sexual sister or closely related ecologically comparable clades. The hypothesis of the preference of asexual species to biotically and abiotically homogenous environments was supported by the results of this metastudy. On the other hand, the hypothesis of supposed ability of asexual species to perfectly adapt to a broader range of environmental conditions, tested on the comparison of temperature ranges of activity of previously...
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Ecological aspects of sexual reproduction
Toman, Jan ; Flegr, Jaroslav (advisor) ; Markoš, Anton (referee)
Sexual reproduction is one of the most interesting biological phenomena. No theory has ever entirely explained its wide occurrence among Eukaryotic clades despite its clear disadvantages (e.g. twofold price of sex). Theories can be divided into three groups according to the approach to solve this problem - molecular, genetic and ecological (environmental). Environmental theories are slightly preferred in the last decades and the opinion that the key to the sex enigma lies among them is widely accepted. Most of the environmental theories do not counter each other and there is possibility either to integrate them in several ways or presume that several of these theories might act simultaneously. According to theories, abiotically stable environments without biotic interactions (homogenous) should be suitable for and select for asexual species, whereas environments abiotically variable and rich in biotic interactions (heterogenous) should be suitable for and select for sexual species. The anagenetic phenomenon of punctuated equilibria and some of its explanations, e.g. P. R. Sheldon's Plus ça change hypothesis or J. Flegr's Frozen plasticity theory, also supports this division. There is a vast amount of empirical data supporting this division in ecological studies. Clearly homogenous environments...
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Macroevolutionary and ecological implications of the theory of frozen plasticity
Toman, Jan ; Flegr, Jaroslav (advisor) ; Fatka, Oldřich (referee) ; Mikuláš, Radek (referee)
The frozen plasticity theory is a punctuationalist theory of adaptive evolution. It states that long periods of stasis, during which populations respond to selection pressures only by elastic change in the frequency of already present alleles, alternate in the evolution of sexual species with short periods of plastic evolution, during which alleles can get fixed or eliminated by directed selection. Asexual species are not expected to maintain such high genetic polymorphism in the long term. They should, however, be able to plastically respond to selection pressures throughout their whole existence. This difference between the evolutionary dynamics of sexual and asexual clades has a number of ecological and macroevolutionary implications. Concerning ecology, we could expect different environmental preferences of sexual and asexual species. Accordingly, in our first work that was based on a comparative study, we statistically significantly supported the hypothesis that (ancient) asexual groups of (eukaryotes) inhabit more stable and homogeneous habitats than their related sexual controls. Focusing on actually experienced, i.e. subjective, heterogeneity of the environment turned out to be the crucial factor of this type of research. From the viewpoint of macroevolutionary implications of the frozen...
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Multilevel selection theory
Mihulka, Tomáš ; Švorcová, Jana (advisor) ; Toman, Jan (referee)
Multilevel selection is an attempt to unify different approaches to the Level of selection problem. This paper examines the principles, starting points, variants and problems of this concept. Particular emphasis is placed on the relationship of this theory to Gene's-eye view and the presentation of evidence of the usefulness of Multilevel selection in analyzing evolutionary changes.
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Macroevolutionary and ecological implications of the theory of frozen plasticity
Toman, Jan ; Flegr, Jaroslav (advisor) ; Fatka, Oldřich (referee) ; Mikuláš, Radek (referee)
The frozen plasticity theory is a punctuationalist theory of adaptive evolution. It states that long periods of stasis, during which populations respond to selection pressures only by elastic change in the frequency of already present alleles, alternate in the evolution of sexual species with short periods of plastic evolution, during which alleles can get fixed or eliminated by directed selection. Asexual species are not expected to maintain such high genetic polymorphism in the long term. They should, however, be able to plastically respond to selection pressures throughout their whole existence. This difference between the evolutionary dynamics of sexual and asexual clades has a number of ecological and macroevolutionary implications. Concerning ecology, we could expect different environmental preferences of sexual and asexual species. Accordingly, in our first work that was based on a comparative study, we statistically significantly supported the hypothesis that (ancient) asexual groups of (eukaryotes) inhabit more stable and homogeneous habitats than their related sexual controls. Focusing on actually experienced, i.e. subjective, heterogeneity of the environment turned out to be the crucial factor of this type of research. From the viewpoint of macroevolutionary implications of the frozen...
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