Student Research Projects

The Effects of Temperature on the Symbiotic Zooxanthellae in Aiptasia pallida

Student Richard Moseley
Faculty Mentor(s)
Department Biology
Course BIO 489: Research in the Natural Sciences


It is known that cnidarians have a symbiotic relationship with the dinoflagellates, zooxanthellae. However, bleaching can undo this relationship with the fluctuation of the ocean’s temperature. It was hypothesized, for this experiment, that cold seawater would expel more zooxanthellae out of the sea anemone, Aiptasia pallida, than warmer seawater. The anemones were placed into a cold shock, heat shock, or control group for six hours, and then given a twelve hour incubation period to allow bleaching to occur. Results showed that heat shock had about 6% higher expulsion rate over cold shock, 25.8% and 20.1% respectfully. It was concluded that different temperatures settings affected how the cells within sea anemones were destroyed, and how much zooxanthellae was expelled out as a result. The heat shock treatment showed to be more effective in expelling zooxanthellae than cold shock during the study, but further tests will have to be conducted to see if there is an overall difference between heat and cold shock.