Thesis (M.S.)--Georgia Southern University, 2004. / "A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Includes bibliographical references (p. 34-42).

Diss. (sammanfattning) Uppsala : Univ., 2009. / Härtill 5 uppsatser.

Thesis (M.S.)--Georgia Southern University, 2006. / "A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science" ETD. Includes bibliographical references (p. 42-48) and appendices.

No description available.

No description available.

Thesis (Ph.D.) - University of St Andrews, February 2008.

Thesis (doctoral)--Rijksuniversiteit te Utrecht, 1983. / Summary also in Dutch. Includes vita. Description based on print version record. Includes bibliographical references.

The focus for the first part of the thesis is on the systematics of species belonging to Silene subgenus Silene. Phylogenetic relationships are inferred from DNA sequences from both the plastid (the rps16 intron) and the nuclear (ITS, intron of the RPB2 gene) genomes. Silene section Rigidulae is shown to be non-monophyletic in its previous circumscription, but instead consisting of six separate clades, each correlated to the geographical distribution of the included species. The taxonomic consequences for each clade are discussed. One of the clades is recognized as a new section and described as Silene sect. Arenosae sect. nov. The morphological descriptions of the species are formalized using a novel implementation of the Prometheus Description Model. Two proposals are included in the thesis, one to reject the name Silene polyphylla L., which is a senior synonym to S. portensis L. Silene linearis Decne. is proposed for conservation against the rarely used S. linearis Sweet. Silene antirrhina, a weedy American annual, is strongly supported as sister to the Hawaiian endemic species of Silene, suggesting an American origin for these. Two of the endemics have evolved woodiness after introduction to Hawaii. In the second part of the thesis we use four nuclear DNA regions, (introns from RPA2, RPB2, RPD2a, RPD2b), and the chloroplast psbE-petG spacer. A framework is developed to evaluate different phylogenetic explanations for conflicting gene trees, where divergence times are used to discriminate among inter- and intralineage processes. The incongruences observed regarding the relationships among the three major lineages of Heliosperma are best explained by homoploid hybridization. The pattern regarding the origin of Heliosperma itself is more complicated and is likely to include several reticulate events. Two lineages have probably been involved in the origin of Heliosperma, one leading to Viscaria and Atocion and the other to Eudianthe and/or Petrocoptis.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2006. / Härtill 6 uppsatser.

Ecological differentiation and adaptation are processes that can drive divergence and speciation. Measuring ecologically revenant traits can help to identify possible targets of natural selection that may have mediated ecological differentiation. This study looked for evidence of within and between species differentiation in seven ecologically relevant traits in two closely related species sampled across their range, and whether any of these traits were related to climate differences among site of origin. We measured seven traits under common garden conditions in seedlings of Silene dioica (11 populations, n=528) and Silene latifolia (14 populations, n=672) grown in the botanical garden in Uppsala in a randomised block design. Three traits related to leaf morphology were measured, and four related to water usage of the plant were measured. These traits were analysed for differences between the species as well as for differences within each species between populations using a linear mixed model. The traits’ relationship to a climate variable, derived from the axes of a principal components analysis of climate data for each site, was investigated using a linear model. A number of drought avoidance (e.g. succulence, max turgid weight) and morphological traits (e.g. leaf ratio) differed between the two species. Water use efficiency has been flagged before as possibly driving ecological differentiation between the two species and the results identify possible candidate traits for quantifying this separation. Differentiation between populations within each species was also present in two traits within S. latifolia and in four traits within S. dioica significantly varying between the populations. This could reflect either local adaptation or genetic drift acting on populations across the range. One trait related to the amount of water taken up by the leaf (wgain) was found to be significantly associated with the climate variable, which was extracted from the principal components analysis, in S. latifolia. The results identified a number of candidate traits which could reflect ecological differences between the species especially with respect to water relations. These traits may allow the species to respond differently during periods of water stress, which in turn could result in ecological separation of the species and determine their geographical ranges.