Sökning: "polyploidy"
Visar resultat 1 - 5 av 22 avhandlingar innehållade ordet polyploidy.
1. Evolution of asexuality in insects : Polyploidy, hybridization and geographical parthenogenesis
Sammanfattning : Asexual reproduction and polyploidy are relatively rare in animals with chromosomal sex determination and always represent a derived condition. To accomplish asexual reproduction several changes in gene expression are required in the mechanism of oogenesis. LÄS MER
2. Plant polyploidy and interactions with insect herbivores
Sammanfattning : Polyploidization has been suggested to be a common mechanism for plant speciation. Polyploidy is associated with changes in plant traits and altered habitat preference. LÄS MER
3. Systematics and polyploid evolution in Potentilleae (Rosaceae)
Sammanfattning : This thesis comprises studies of the phylogenetic relationships in the flowering plant clade Potentilleae in Rosaceae. The relationships were elucidated by using DNA sequence data from the nuclear genome as well as from the plastid genome. In particular, the focus of the studies was the investigation of allopolyploidy, i.e. LÄS MER
4. Reticulate Evolution in Diphasiastrum (Lycopodiaceae)
Sammanfattning : In this thesis relationships and the occurrence of reticulate evolutionary events in the club moss genus Diphasiastrum are investigated. Diphasiastrum is initially established as a monophyletic group within Lycopodiaceae using non recombinant chloroplast sequence data. LÄS MER
5. Genomic and phenotypic consequences of allopolyploidization in Capsella
Sammanfattning : Allopolyploidization, the combination of whole-genome duplication (WGD) and interspecific hybridization, is a frequent and influential event in plant evolution. Allopolyploidization potentially affects both adaptation and diversification, yet the understanding of the consequences of allopolyploidy has been obscured by several issues. LÄS MER