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Cerebral laterality in birds and mammals, its behavioral correlation and evolutionary significance
Tureček, Petr ; Komárek, Stanislav (advisor) ; Němec, Pavel (referee)
Lateralization of brain is ubiquitous quality of vertebrate brain. In this paper we rewiev examples of brain lateralization in birds and mammals and it's behavioral impacts. Than we discuss possible evolutionary origins of these asymmetries and their evolutionary significance. We try to explain individual as well as population level lateralization. We propose, that population level lateralization can, in principle, arise just on the genofondal basis, if the organism itself contributes to the enviroment with the lateralized behavior. Lateralized sensory input on the other hand should stand on the advantages of synchronizing with other individuals due to the disatvantage of predictability of lateralized population. Keywords: Lateralization; laterality; population level lateralization; asymmetry; evolutionary significance
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The significance of silica structures in chromist microorganisms.
Nováková, Dora ; Škaloud, Pavel (advisor) ; Němcová, Yvonne (referee)
The silica is one of the most common elements in the Earth's crust. During erosion it is released in soluble form to the environment, where some organisms can accumulate the silica and incorporate it to their bodies by biosilicification process. The organsims possessing this ability are widespread either when considering their position in eukaryotic tree of life, or their abundance in natural ecosystems. As a result, the whole global biogeochemical cycle of silica is controlled by biosilicificated organisms. In Chromista microorganisms, the silica is loaded to so-called "silica deposition vesicles" - membrane surrounded compartments, in which the silica is polymerated and formed into the final shape of silica structures during an ingeniously controlled in vivo process. Apparent differences in the process of silica deposition among Chromista microorganisms imply that this ability has developed independenty and repeatedly within the group. The most common silica structures are scales, bristles, cases, skeletons and cysts. The analogical structures often originated independently in unrelated lines of Chromista by means of convergent evolution. On the contrary, in some lineages of Chromista, the ability of biosilicification was suppressed. It is therefore very likely that the silica structures should...
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The significance of silica structures in chromist microorganisms.
Nováková, Dora ; Škaloud, Pavel (advisor) ; Němcová, Yvonne (referee)
The silica is one of the most common elements in the Earth's crust. During erosion it is released in soluble form to the environment, where some organisms can accumulate the silica and incorporate it to their bodies by biosilicification process. The organsims possessing this ability are widespread either when considering their position in eukaryotic tree of life, or their abundance in natural ecosystems. As a result, the whole global biogeochemical cycle of silica is controlled by biosilicificated organisms. In Chromista microorganisms, the silica is loaded to so-called "silica deposition vesicles" - membrane surrounded compartments, in which the silica is polymerated and formed into the final shape of silica structures during an ingeniously controlled in vivo process. Apparent differences in the process of silica deposition among Chromista microorganisms imply that this ability has developed independenty and repeatedly within the group. The most common silica structures are scales, bristles, cases, skeletons and cysts. The analogical structures often originated independently in unrelated lines of Chromista by means of convergent evolution. On the contrary, in some lineages of Chromista, the ability of biosilicification was suppressed. It is therefore very likely that the silica structures should...
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Cerebral laterality in birds and mammals, its behavioral correlation and evolutionary significance
Tureček, Petr ; Komárek, Stanislav (advisor) ; Němec, Pavel (referee)
Lateralization of brain is ubiquitous quality of vertebrate brain. In this paper we rewiev examples of brain lateralization in birds and mammals and it's behavioral impacts. Than we discuss possible evolutionary origins of these asymmetries and their evolutionary significance. We try to explain individual as well as population level lateralization. We propose, that population level lateralization can, in principle, arise just on the genofondal basis, if the organism itself contributes to the enviroment with the lateralized behavior. Lateralized sensory input on the other hand should stand on the advantages of synchronizing with other individuals due to the disatvantage of predictability of lateralized population. Keywords: Lateralization; laterality; population level lateralization; asymmetry; evolutionary significance
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