velikost textu

Phylogeny, phylogeography and taxonomy of selected members of the family Bosminidae

Upozornění: Informace získané z popisných dat či souborů uložených v Repozitáři závěrečných prací nemohou být použity k výdělečným účelům nebo vydávány za studijní, vědeckou nebo jinou tvůrčí činnost jiné osoby než autora.
Název:
Phylogeny, phylogeography and taxonomy of selected members of the family Bosminidae
Název v češtině:
Fylogeneze, fylogeografie a taxonomie vybraných zástupců čeledi Bosminidae
Typ:
Disertační práce
Autor:
Mgr. Markéta Faustová, Ph.D.
Školitel:
RNDr. Veronika Sacherová, Ph.D.
Oponenti:
prof. RNDr. Igor Hudec, CSc
prof. Dr. Klaus Schwenk
Id práce:
30823
Fakulta:
Přírodovědecká fakulta (PřF)
Pracoviště:
Katedra ekologie (31-162)
Program studia:
Biologie (P1501)
Obor studia:
Hydrobiologie (XHYDR)
Přidělovaný titul:
Ph.D.
Datum obhajoby:
9. 9. 2010
Výsledek obhajoby:
Prospěl/a
Informace o neveřejnosti:
Práce byla vyloučena ze zveřejnění.
Jazyk práce:
Angličtina
Abstrakt:
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 morphotypes reflected in paleolimnological record with the possible implications for origin of such plasticity, and what can be learned from the mitochondrial genome of eubosminas compared to other cladocerans. Presented thesis is a summary of following manuscripts: I. Coexisting Cyclic Parthenogens Comprise a Holocene Species Flock in Eubosmina II. Radiation of the European Eubosmina (Cladocera) from Eubosmina longispina – a concordance of multipopulation molecular data with paleolimnology III. The comparison of mitochondrial genomes of three cladoceran species; Bosmina (E.) coregoni, Bosmina (E.) tanakai, and Chydorus brevilabris (Branchiopoda; Crustacea) The major conclusions of the thesis can be summarized as follows: 1. The hypothesis that morphotypes (morphospecies) of Eubosmina lack morphological and genetical discreteness under sympatry is rejected. Instead, the results are consistent with the establishment of Holocene reproductive barriers as predicted by the paleolimnological record. 2. Studied Eubosmina morphotypes represent a group of young species undergoing speciation with apparent reproductive barriers despite coexistence in the relatively homogenous freshwater pelagic zone. 3. Even if mixed breeding system that are considered to impede the formation of discrete evolutionary clusters, Eubosmina group is associated with some of the most rapid radiations known in animals. 4. European morphotypes radiated from longispina morphotype as suggested by the results and are supported by the paleolimnological record and biogeographical pattern. Thus longispina spread most likely from one main refugia at the end of late Pleistocene. 5. Some morphotypes (morphospecies) have apparently evolved in a parallel fashion, thus they consist of several cryptic lineages. 6. The incomplete lineage sorting is expected in young radiations and together with multiple origins of the morphospecies cause difficulties in species delimitation in Eubosmina. 7. The Eubosmina group presents a case where morphology and haplotype sharing are more informative for species boundaries than mtDNA sequence divergences. Nevertheless, there is intense demand for 1) more sensitive tools and different approaches to detect young radiations species flocks and 2) species definition and delimitation in case of species with polyphyletic origin and incomplete lineage sorting as suggested for Eubosmina. 8. Eubosmina taxonomical systems based on morphology should be treated with awareness of presented genetic results and subspecies and species should be regarded as morphospecies/morphotypes. Subsequent analyzes are necessary to test if biological species concept or related concepts can be safely applied on Eubosmina morphotypes (morphospecies).
Abstract v angličtině:
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 morphotypes reflected in paleolimnological record with the possible implications for origin of such plasticity, and what can be learned from the mitochondrial genome of eubosminas compared to other cladocerans. Presented thesis is a summary of following manuscripts: I. Coexisting Cyclic Parthenogens Comprise a Holocene Species Flock in Eubosmina II. Radiation of the European Eubosmina (Cladocera) from Eubosmina longispina – a concordance of multipopulation molecular data with paleolimnology III. The comparison of mitochondrial genomes of three cladoceran species; Bosmina (E.) coregoni, Bosmina (E.) tanakai, and Chydorus brevilabris (Branchiopoda; Crustacea) The major conclusions of the thesis can be summarized as follows: 1. The hypothesis that morphotypes (morphospecies) of Eubosmina lack morphological and genetical discreteness under sympatry is rejected. Instead, the results are consistent with the establishment of Holocene reproductive barriers as predicted by the paleolimnological record. 2. Studied Eubosmina morphotypes represent a group of young species undergoing speciation with apparent reproductive barriers despite coexistence in the relatively homogenous freshwater pelagic zone. 3. Even if mixed breeding system that are considered to impede the formation of discrete evolutionary clusters, Eubosmina group is associated with some of the most rapid radiations known in animals. 4. European morphotypes radiated from longispina morphotype as suggested by the results and are supported by the paleolimnological record and biogeographical pattern. Thus longispina spread most likely from one main refugia at the end of late Pleistocene. 5. Some morphotypes (morphospecies) have apparently evolved in a parallel fashion, thus they consist of several cryptic lineages. 6. The incomplete lineage sorting is expected in young radiations and together with multiple origins of the morphospecies cause difficulties in species delimitation in Eubosmina. 7. The Eubosmina group presents a case where morphology and haplotype sharing are more informative for species boundaries than mtDNA sequence divergences. Nevertheless, there is intense demand for 1) more sensitive tools and different approaches to detect young radiations species flocks and 2) species definition and delimitation in case of species with polyphyletic origin and incomplete lineage sorting as suggested for Eubosmina. 8. Eubosmina taxonomical systems based on morphology should be treated with awareness of presented genetic results and subspecies and species should be regarded as morphospecies/morphotypes. Subsequent analyzes are necessary to test if biological species concept or related concepts can be safely applied on Eubosmina morphotypes (morphospecies).
Dokumenty
Stáhnout Dokument Autor Typ Velikost
Stáhnout Text práce Mgr. Markéta Faustová, Ph.D. 4.3 MB
Stáhnout Abstrakt v českém jazyce Mgr. Markéta Faustová, Ph.D. 17 kB
Stáhnout Abstrakt anglicky Mgr. Markéta Faustová, Ph.D. 17 kB
Stáhnout Posudek oponenta prof. RNDr. Igor Hudec, CSc 171 kB
Stáhnout Posudek oponenta prof. Dr. Klaus Schwenk 1.13 MB
Stáhnout Záznam o průběhu obhajoby 578 kB