Skip to main content
Skip to main menu Skip to spotlight region Skip to secondary region Skip to UGA region Skip to Tertiary region Skip to Quaternary region Skip to unit footer


Claire Zwiers-Cook

Blurred image of the arch used as background for stylistic purposes.
Doctoral Graduate Research Assistant

Mixotrophic protists serve a unique role in marine environments, performing both photosynthesis and phagotrophy as forms of metabolism. While mixotrophic organisms are key contributors to primary production and remineralization in several ecosystems, relatively little is known about the roles they play in trophic structure and biogeochemical cycling. Mixotrophs are hypothesized to increase trophic transfer efficiency and contribute heavily to the deep ocean transport of carbon, allowing this group to contribute to multiple facets of the microbial loop and biological carbon pump. Metabolisms of these organisms are key to incorporating into model predictions of biogeochemical carbon cycling, yet large unknowns exist regarding their ecology and physiology.


I study mixotrophic metabolisms in the Southern Ocean where both iron (Fe) and manganese (Mn) are in low concentrations but needed to perform photosynthesis. Through analysis of the physiology of Antarctic mixotrophs, I work to quantify and characterize where and how mixotrophic metabolisms might be beneficial in trace metal-limited areas.



Collaborators: Nicole Millette (VIMS), Becky Gast (WHOI)

Supported by NSF Office of Polar Programs

B.S University of Michigan. Majors: Ecology, Evolution, and Biodiversity; Honors in Earth and Environmental Science

Major Professor

Support us

We appreciate your financial support. Your gift is important to us and helps support critical opportunities for students and faculty alike, including lectures, travel support, and any number of educational events that augment the classroom experience. Click here to learn more about giving.

Every dollar given has a direct impact upon our students and faculty.