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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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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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Simulations of open-ended evolution
Prax, Sebastian ; Toman, Jan (advisor) ; Tureček, Petr (referee)
Evolutionary algorithms are used to solve a number of optimization problems in the computer science. At the same time, they are fundamental pillar for creating evolutionary simulations and testing scientific hypotheses in a various areas of theoretical biology. In the first half of my work, I characterize the concept of "open-ended evolution", focus on its connection with the technical side of simulations and introduce readers to the problematics of system simulation. Further on, I deal with the phenomenon of increasing complexity and the idea of "evolutionary progress". All these topics are confronted with various perspectives of researchers in the field of evolutionary biology. In the second half, I summarize the benefits of existing projects for evolutionary biology and applied informatics, as well as the ways in which the simulations of open-ended evolution can be approached. Basically, these projects can be divided into two categories. They are either projects in which individuals develop towards a predefined goal, which is conditioned by a fitness function, or projects of researchers who seek to achieve an open-ended evolution by employing biologically realistic design of the genetic code and environment in conjunction with the absence of a particular attractor in the evolution of virtual...
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