Student Research Symposium

Permanent URI for this communityhttps://hdl.handle.net/1969.3/29764

The Texas A&M University at Galveston (TAMUG) Student Research Symposium provides a venue for the exposure of student research to the broader TAMUG community. For more information, see http://www.tamug.edu/research/Symposium/.

Student participants in the Research Symposium may publish their papers, posters, and research data in TAMUG's open access repositories.

Browse

Browsing Student Research Symposium by Author "Borda, Elizabeth"

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Eurythoe complanata: more cryptic species in the Pacific?
    (2012-06-01) Johnson, Marandia; Borda, Elizabeth; Schulze, Anja
    Mitochondrial DNA data has shown that Eurythoe complanata is a cryptic species complex characterized by deeply divergent sympatric populations in the Atlantic, and on either side of Panama, despite almost no morphological differences. Previous work examined populations primarily in the Caribbean and Atlantic Ocean, with little exploration of the phylogenetic relationships of Pacific populations. We aim to study these relationships using nuclear (ITS-1) and mitochondrial (COI and 16S rDNA) sequence data. We include representatives from populations in the east Pacific (Mexico and the Gulf of California), Indo-Pacific (Indonesia, Moorea and American Samoa), and from aquaria. The objectives of this study are to: 1) identify if there are cryptic species in the Pacific; 2) infer the phylogenetic relationships among amphi-Pacific populations; and 3) estimate the distributional patterns of animals that reproduce both sexually and asexually.
  • No Thumbnail Available
    Item
    Genotypic diversity of Sabellid worms from carbon dioxide vents
    (2012-06-01) de Guzman, Heidi Jane; Borda, Elizabeth; Schulze, Anja
    Marine carbon dioxide vents are very common in the Mediterranean Sea, especially around Italy and Greece where they typically eject volcanic fluids containing up to 1-2% hydrogen sulfide. Natural CO2 venting sites have endemic fauna unique to them, and vent communities are generally distinct from the surrounding waters. In the Mediterranean Sea, the sabellid polychaete Amphiglena mediterranea is reported as one of the most common species associated with shallow carbon dioxide vents covered with photophilic algae. The aim of this study is to determine the genotype diversity of A. mediterranea exposed to low pH conditions, from the cold carbon dioxide vents of the island of Ischia, Italy and compare it to that of populations at non-acidified control sites. Specimens were collected from four different CO2 vents sites with different pH concentrations. Genotype diversity between different populations of the Mediterranean sabellid Amphiglena mediterranea are being investigated through the use of the mitochondrial cytochrome c oxidase I (COI) gene. Based on the above objective, the following null hypothesis will be tested: There is no significant difference in the genotype diversity in A. mediterranea population from acidified and non-acidified locations
  • No Thumbnail Available
    Item
    High degree of connectivity among amphi-Atlantic populations of Hermodice carunculata (Amphinomidae, Annelida)
    (2012-06-01) Ahrens, Joseph; Borda, Elizabeth; Campbell, Alexandra; Schulze, Anje
    Polychaete annelids in the genus Hermodice exhibit an amphi-Atlantic distribution extending into the Gulf of Mexico as well as the Caribbean and Mediterranean Seas. Currently, this genus contains two nominal species; H. carunculata, which inhabits the Greater Caribbean, and H. nigrolineata which is found in the Mediterranean and along the African Atlantic coast. In this study, we analyzed DNA sequence data from specimens in the Gulf of Mexico (GoM), the Mediterranean and Caribbean Seas to estimate population structure and phylogeographic patterns for Hermodice. Analysis of mitochondrial cytochrome oxidase subunit I (COI) and 16s rDNA indicates low levels of divergence between Greater Caribbean and Mediterranean specimens. Additionally, at least three outliers from Mediterranean populations cluster with Greater Caribbean specimens in phylogenetic analyses. Our results provide no support for the distinction between H. carunculata and H. nigrolineata and stress the importance of including molecular data as a criterion for delimiting species. Whereas other genetic studies of marine taxa often reveal the presence of cryptic species complexes, our study indicates high population connectivity across a wide geographic range for H. carunculata.
Authors grant a nonexclusive license for Texas A&M University at Galveston to publish the works in this archive. Authors retain all copyright.