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Theses/Dissertations

Dissertations, Theses, and Masters Projects

Molecular Biology

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Full-Text Articles in Ecology and Evolutionary Biology

Understanding The Origins, Dispersal, And Evolution Of Bonamia Species (Phylum Haplosporidia) Based On Genetic Analyses Of Ribosomal Rna Gene Regions, Kristina M. Hill Jan 2011

Understanding The Origins, Dispersal, And Evolution Of Bonamia Species (Phylum Haplosporidia) Based On Genetic Analyses Of Ribosomal Rna Gene Regions, Kristina M. Hill

Dissertations, Theses, and Masters Projects

No abstract provided.


A Molecular Phylogeny Of The Genus Bonamia Based On Sequence Data Of The Ribosomal Rna (Rrna) Gene Complex, Delonna M. White Jan 2008

A Molecular Phylogeny Of The Genus Bonamia Based On Sequence Data Of The Ribosomal Rna (Rrna) Gene Complex, Delonna M. White

Dissertations, Theses, and Masters Projects

No abstract provided.


Synalpheus Shrimp From Carrie Bow Cay, Belize. Systematics, Phylogenetics And Biological Observations (Crustacea: Decapoda: ; Alpheidae), Ruben Rios Gonzalez Jan 2003

Synalpheus Shrimp From Carrie Bow Cay, Belize. Systematics, Phylogenetics And Biological Observations (Crustacea: Decapoda: ; Alpheidae), Ruben Rios Gonzalez

Dissertations, Theses, and Masters Projects

Snapping shrimp in the family Alpheidae are remarkably abundant in coral reef ecosystems worldwide. The second most speciose genus, Synalpheus , includes species usually small and reclusive, and their general morphology is notably uniform, yet the number of species is staggeringly high, as is the intraspecific variability. These features have contributed to a poorly resolved taxonomic status, as evidenced both by recurring lumping and splitting of species and by lack of proper definition of several common species. I examined western Atlantic species of Synalpheus in the large and regionally dominant "Gambarelloides group of species", an informal but widely used guild …


Molecular And Morphological Evolution Of The Amphipod Radiation Of Lake Baikal, Kenneth S. Macdonald Iii Jan 2002

Molecular And Morphological Evolution Of The Amphipod Radiation Of Lake Baikal, Kenneth S. Macdonald Iii

Dissertations, Theses, and Masters Projects

The amphipods of Lake Baikal, Russia, are a taxonomically and morphologically diverse group, and have been cited as a classic example of adaptive radiation. An unfortunate consequence of this diversity has been an instability of Baikal amphipod classification, with frequent revisions spurred by differing opinions about the phylogenetic utility of different characters. Classifications have never been based on a rigorous phylogenetic analysis of morphological data and only recently has the phylogeny of Lake Baikal's amphipods been examined using molecular tools. Unfortunately, most of these studies have led to a limited expansion of our understanding of Baikal amphipod systematics. Phylogenetic relationships …


Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr Jan 1999

Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr

Dissertations, Theses, and Masters Projects

Lipid quality was evaluated in Montastrea spp. under sediment- and heat-stressed conditions to evaluate lipid ratio as an indicator of sub-lethal stress on short time scales. The ratio of storage lipid (wax ester + triacylglyceride) to structural lipid (sterol esters + phospholipid) decreased significantly (0.25 to 0.14, p < 0.01) after experimental sedimentation. FAME analysis of colonies exposed to experimental sedimentation showed a reduction of the algal, 18:3(n-6) and 18:4(n-3), polyunsaturated fatty acid (PUFA) in the polar lipid fraction. This loss of PUFA suggests a loss of algal membrane in sediment-stressed colonies. Lipid quality was similarly measured in M. faveolata over a 10-day period. Mean (n = 20) ratio of storage to structural lipid in M. faveolata dropped from 2.43 to a level of 0.98 immediately following a natural sedimentation event before recovering to levels of 1.4 and 2.9 on post-storm days 2 and 4, respectively. Colonies of M. annularis subject to heat-stress (35??C) exhibited no significant change in storage lipid ratio, while levels of Free Fatty Acids increased significantly from 0.012 (n = 22) to 0.156 mg lipid/g dry tissue (n = 22)(p < 0.05). FAME analysis of tissue lipids extracted from the heat-stressed colonies showed changes in the polar fraction, with significant decreases in the 18:3(n-6), 18:3(n-3), 18:4(n-3), 20:4(n-6) and 20:5(n-3) (p < 0.05) PUFA and subsequent significant increases in the saturated fatty acids, 16:0 and 18:0 (p < 0.05). These changes in lipid quantity and quality indicate possible oxidation and preferential digestion of zooxanthellar membranes. Stress experiments were repeated in M. annularis using VacutainerRTM blood collection tubes to collect micro-tissue samples without destroying skeleton of the sample colonies. A significant decrease in storage: structural lipid ratio after sedimentation was also detected using the micro-tissue technique. This study indicates that the relative abundance of lipid subclass components can indicate sub-lethal environmental stress, on short time scales, in M. annularis and M. faveolata. Furthermore, micro-tissue collection techniques permit repeated monitoring coral colonies to assess the manifestation of stress from first detection of impact at the cellular level to changes in community to changes in community structure detectable over longer time scales.


Phylogeny Of The Haplosporidia (Eukaryota: Alveolata) Based On Small Subunit Ribosomal Rna Gene Sequence, Brenda Sandy Flores Jan 1996

Phylogeny Of The Haplosporidia (Eukaryota: Alveolata) Based On Small Subunit Ribosomal Rna Gene Sequence, Brenda Sandy Flores

Dissertations, Theses, and Masters Projects

No abstract provided.