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Alternative Title

Symbiont contributions to the sea anemone (Exalptasia pallida) stress response

Publication Date


First Advisor

Rachel M. Wright

Document Type

Honors Project

Degree Name

Bachelor of Arts


Biological Sciences


Corals, Reefs, Exalptasia pallida, Light stress, Nutrient stress, Clonal lines, Climate change, Cnidarians, Anemones, Symbiosis, Aposymbiosis


Coral reefs are hotspots for oceanic biodiversity, industry, and protection. Hidden within them is a complex relationship (symbiosis) between the coral host and photosynthetic algae that allows both organisms to thrive by working together as one. Climate change threatens to destabilize this symbiosis and ultimately impact the survival of coral reefs as a whole by increasing the occurrence of coral bleaching, leaving corals vulnerable to starvation and disease. The role of individual climate change-related stressors in triggering bleaching is largely unknown. This thesis explores the distinct roles played by cnidarian host and endosymbiont in response to single and combined stress, by assessing mortality, algal density, and reactive oxygen species presence in the sea anemone Exaiptasia pallida in symbiosis, aposymbiosis, and separate algal culture. Preliminary results indicate that stress treatment and symbiotic state are significant predictors of anemone mortality, particularly when combined. These findings support theories of coral bleaching as an end result of destabilizing the cnidarian-algal symbiosis, potentially by means of a shift from mutualism to parasitism when placed under sufficient stress. These limited data are highly encouraging of further planned research, including metabolic and transcriptomic assessment.


©2021 Quinton Oliver Celuzza




49 pages : color illustrations Includes bibliographical references (pages 42-49)