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Phylogeny, phylogeography and taxonomy of selected members of the family Bosminidae
Faustová, Markéta ; Sacherová, Veronika (advisor) ; Hudec, Igor (referee) ; Schwenk, Klaus (referee)
Phylogeography, taxonomy, and systematics of chosen members of family Bosminidae Abstract of Ph.D. Thesis MSc Markéta Faustová Supervisors: RNDr. Veronika Sacherová, Ph.D. - Charles University in Prague, Czech Republic Dr. Derek J. Taylor, Ph.D. - New York State University at Buffalo, U.S.A. For their life cycles, phenotypic plasticity, presence of sibling species and worldwide distribution, cladocerans are useful organisms for evolutionary studies with the aim to understand mechanisms of speciation, adaptive radiation, and polymorphism. While members of the genus Daphnia (family Daphniidae) became an iconic model in such studies, members of the family Bosminidae posses comparably interesting set of characteristics that could help to elucidate speciation mechanisms. In particular, members of the genus Eubosmina are known for extreme levels of phenotypic plasticity, especially in the Circumbaltic region, which puzzled the taxonomy and confused relationships of all described morphotypes since the first Eubosmina was described in 1857. The presented thesis explores genetic and morphometrical relationships with the aim to clarify how closely related all the described morphospecies are, to find out if there are some reproductive barriers and how strong these barriers are, how is the present-day structure of...
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Genetic structure of the Daphnia longispina complex in European mountain lakes
Hamrová, Eva ; Petrusek, Adam (advisor) ; Schwenk, Klaus (referee) ; Hobaek, Anders (referee)
I studied the genetic structure of cladocerans from the Daphnia longispina complex in several European mountain ranges. The population genetic structure of the D. longispina complex was studied using mitochondrial (mtDNA; partial sequencing of the 12S rRNA gene) and nuclear markers (nine microsatellite loci). Major part of the work was done in the Tatra Mountains; the genetic structure of populations of the Daphnia longispina complex from two parts of this range (the West and the High Tatras) was compared. The pattern of mtDNA confirmed multiple colonization of lakes from different source populations, detected haplotype diversity was high and haplotype sharing only within the West or the High Tatras was observed. The observed genetic differentiation indicates low level of gene flow and persistent founder effect, consistent with the monopolization hypothesis. The alternation of asexual and sexual reproduction in the life cycle of Daphnia, cyclical parthenogenesis, may affect genetic structure of their populations. This was the topic of a study described in the first chapter. A detailed analysis of population structure of two closely related Daphnia species (D. galeata and D. longispina) living in similar habitats (permanent dimictic mountain lakes) in the Tatra Mountains revealed that populations...
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Genetic structure of the Daphnia longispina complex in European mountain lakes
Hamrová, Eva ; Petrusek, Adam (advisor) ; Schwenk, Klaus (referee) ; Hobaek, Anders (referee)
I studied the genetic structure of cladocerans from the Daphnia longispina complex in several European mountain ranges. The population genetic structure of the D. longispina complex was studied using mitochondrial (mtDNA; partial sequencing of the 12S rRNA gene) and nuclear markers (nine microsatellite loci). Major part of the work was done in the Tatra Mountains; the genetic structure of populations of the Daphnia longispina complex from two parts of this range (the West and the High Tatras) was compared. The pattern of mtDNA confirmed multiple colonization of lakes from different source populations, detected haplotype diversity was high and haplotype sharing only within the West or the High Tatras was observed. The observed genetic differentiation indicates low level of gene flow and persistent founder effect, consistent with the monopolization hypothesis. The alternation of asexual and sexual reproduction in the life cycle of Daphnia, cyclical parthenogenesis, may affect genetic structure of their populations. This was the topic of a study described in the first chapter. A detailed analysis of population structure of two closely related Daphnia species (D. galeata and D. longispina) living in similar habitats (permanent dimictic mountain lakes) in the Tatra Mountains revealed that populations...
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Phylogeny, phylogeography and taxonomy of selected members of the family Bosminidae
Faustová, Markéta ; Sacherová, Veronika (advisor) ; Hudec, Igor (referee) ; Schwenk, Klaus (referee)
Phylogeography, taxonomy, and systematics of chosen members of family Bosminidae Abstract of Ph.D. Thesis MSc Markéta Faustová Supervisors: RNDr. Veronika Sacherová, Ph.D. - Charles University in Prague, Czech Republic Dr. Derek J. Taylor, Ph.D. - New York State University at Buffalo, U.S.A. For their life cycles, phenotypic plasticity, presence of sibling species and worldwide distribution, cladocerans are useful organisms for evolutionary studies with the aim to understand mechanisms of speciation, adaptive radiation, and polymorphism. While members of the genus Daphnia (family Daphniidae) became an iconic model in such studies, members of the family Bosminidae posses comparably interesting set of characteristics that could help to elucidate speciation mechanisms. In particular, members of the genus Eubosmina are known for extreme levels of phenotypic plasticity, especially in the Circumbaltic region, which puzzled the taxonomy and confused relationships of all described morphotypes since the first Eubosmina was described in 1857. The presented thesis explores genetic and morphometrical relationships with the aim to clarify how closely related all the described morphospecies are, to find out if there are some reproductive barriers and how strong these barriers are, how is the present-day structure of...
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