HOW DIVERSE ARE CORAL-BORING MUSSELS ACROSS THE PACIFIC?

Open Access
- Author:
- Quiggle, Tanner
- Area of Honors:
- Biology
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Iliana Brigitta Baums, Thesis Supervisor
Daniel J Cosgrove, Thesis Honors Advisor - Keywords:
- Diversity
Mussel
Coral
Pacific Ocean
CO1
Climate Change - Abstract:
- Coral reefs provide an important reservoir for biodiversity, and they are an integral part of the culture and economy of many island nations across the globe. Reefs form the foundation of islands inhabited by humans and protect the shoreline from erosion. The coral reefs also serve as important food sources. Nonetheless, climate change and pressure from invasive species are degrading them. For example, boring mussels in the genus Lithophaga infest Porites corals. The Lithophaga larvae are able to overcome the stinging cells that the corals use to defend themselves against invaders and bore into the coral skeleton. This destabilizes the coral colonies and can cause bioerosion. Certain species of Porites coral are more susceptible to the larvae, suggesting a species-specific interaction. Therefore, it is proposed here that mussel diversity in the Pacific Ocean follows a diversity gradient similar to that of the corals, where the highest diversity is found in the Indo-Pacific Region and gradually declines towards the east. In order to investigate this hypothesis, the cytochrome c oxidase I (CO1) region of mitochondrial DNA of the mussels was sequenced to look for a constant association between a dominant species of coral, Porites lobata, and a lesser species, Porites evermanni, and mussels across the Western, Central, and Eastern Pacific Ocean. Contrary to expectation, it was discovered that the mussels were actually of the genus Leiosolenus and not Lithophaga. Further, it was found that one species of mussel, Leiosolenus hanleyanus is predominately found in Porites corals across the Ocean. This is significant because the mussels and coral maintained that relationship through the Eastern Pacific Barrier, a 3000 km stretch of open ocean. This is the first report of L. hanleyanus east of the Central Pacific. Population genetic structure was similar in mussels and corals where the eastern populations were differentiated from other populations to the west.