Environmental Internship Program - 2022 Booklet

BIODIVERSITY AND
CONSERVATION
Noreen Hosny ’25
MOLECULAR BIOLOGY
Certificates: Environmental Studies, Visual Arts
PROJECT TITLE
Analysis of Climate-driven
Body-size Changes in the
Marine Fossil Record
ORGANIZATION(S)
Deutsch Research
Group, Department of
Geosciences, Princeton
University
LOCATION(S)
Princeton, New Jersey
MENTOR(S)
Curtis Deutsch,
Professor of Geosciences
and the High Meadows
Environmental Institute
As ocean temperatures rise, dissolved oxygen
decreases. Yet, marine life requires more oxygen
in warmer environments. This inconsistency
may shape organisms’ adpatations by causing
them to mature at smaller body sizes. I sought
to quantify and understand how climate-driven
changes to temperature and oxygen affect the
body size of benthic (bottom-dwelling) and
planktonic (surface-dwelling) foraminifera
(single-celled zooplankton). I used temperature
and body size data collected from previous
literature to calculate and visualize the
temperature size effect (TSE) in the program
MATLAB for various foraminifera species. We
observed very large TSE values and concluded
that temperature alone cannot justify these
body size changes. I next investigated how the
species’ metabolic index (MI) is affected by
these changes, since MI accounts for oxygen
and temperature simultaneously. I created a
trait database documenting the body mass
changes and respiration rates and then analyzed
these variables in MATLAB to find that oxygen
limitation plays a primary role in body size
variation. I learned about the pressing effect
of climate change on marine biodiversity,
which informed my decision to pursue an
Environmental Studies certificate. I hope to take
environmental science and policy classes to
further inform my climate science research.
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