Undergraduate Research: An Archive - 2021 Program

Janaya Bruce ’21
MOLECULAR BIOLOGY
Certificate in Environmental Studies
THESIS TITLE
How Do Coral Reefs
Respond to Climate
Change? Investigating
the Role of
Symbiodiniaceae
Community Composition
on Coral Performance
Under Long-Term
Exposure to Warming
and Acidification
ADVISERS
José Avalos, Assistant
Professor of Chemical
and Biological
Engineering and the
Andlinger Center for
Energy and the
Environment; Robert
Toonen, Professor,
Hawai'i Institute of
Marine Biology,
University of Hawai'i at
Mānoa
Changes in environmental factors can cause
coral to expel their endosymbiotic community
of algae in the family Symbiodiniaceae, leaving
coral vulnerable to disease and mortality. One
method through which coral can acclimatize to
fluctuations in ocean temperature is by shuffling
their Symbiodiniaceae community to increase
relative proportions of temperature-tolerant
symbionts. I conducted a two-year mesocosm
experiment investigating the effects of long-term
exposure to ocean acidification and warming on
Symbiodiniaceae communities in eight species
of Hawaiian coral. Coral were collected from six
locations around O'ahu and exposed to endof-century
temperature and pH conditions for
two years. We found that temperature is a more
significant driver of changes to Symbiodiniaceae
community composition than pH in Hawaiian
corals. We additionally demonstrated that
changes in symbiont communities arise from
the shuffling of current symbionts and the
incorporation of novel symbionts from the
environment, which has implications for coral
resilience to future climate change
BIODIVERSITY AND
CONSERVATION
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