In March, researchers published from the most comprehensive survey to date of DNA associated with tiny drifting organisms called plankton in the Southern Ocean surrounding Antarctica. The study stems from nearly a decade of genetic analysis conducted by biogeochemist Nicolas Cassar, Lee Hill Snowdon Bass Chair in the Nicholas School of the Environment, together with researchers from the European Institute for Marine Studies and other international collaborators.

鈥淭he Southern Ocean is massive and plays a disproportionate role in terms of heat and carbon uptake from the atmosphere,鈥 Cassar says. 鈥淲e wanted to better understand microbial diversity in the region, because those microbes affect the carbon cycle in different ways.鈥

Remarkably, at least a third of the genes identified are missing from existing marine gene catalogs, underscoring how little we know about microbial life on our planet, according to Cassar. The next step is to dig deeper into this newfound genetic diversity to ultimately understand how it affects, and is affected by, climate change.  

View from the deck of a research vessel traveling across the Southern Ocean, with open water and a distant coastline under a cloudy sky.
Nicolas Cassar conducted field work in the Southern Ocean over the course of a month, approximately, from this research vessel. Photo courtesy of Nicolas Cassar