CEB Committe on Evolutionary Biology

Brooke Weigel Studies Kelp Microbiome

Brooke puts blades of kelp into enclosed polycarbonate tube chambers to measure nutrient uptake, carbon fixation and microbial nitrogen cycling associated with kelp blades.

Brooke Weigel 8/2018

I am a PhD candidate at the University of Chicago in the Committee on Evolutionary Biology. My research aims to characterize the symbiosis between giant canopy-forming kelp and the millions of tiny bacteria that live on their surfaces. I am determining the identity and functional role of symbiotic bacteria associated with the "bull kelp" Nereocystis luetkeana, which forms extensive underwater forests along the Pacific Coast of the United States and Canada. My research has shown that there are up to 25 million bacteria living on each square centimeter of kelp! Microbial metabolisms may contribute significantly to carbon and nitrogen cycling associated with kelp, which has fueled my desire to characterize the functional importance of this symbiosis. My research has been funded by the Phycological Society of America, National Geographic, and the Committee on Evolutionary Biology.


Each summer, I spend three months in the field on the outer coast of the Olympic Peninsula in Washington, and I travel to a small remote island (Tatoosh Island) with University of Chicago professors Cathy Pfister and Tim Wootton to conduct my field experiments. Tatoosh Island is an ideal location for my research, because it has extremely biodiverse rocky intertidal and kelp forest ecosystems, and the island has been the focus of a number of historic ecological studies since the 1960s. Being at the University of Chicago has given me excellent access to marine biology field stations, including the Marine Biological Lab in Woods Hole. In addition to working on kelp, I am also using the unique evisceration and regeneration capacity of sea cucumbers (holothurians) as a novel system to study colonization and succession of the gut microbiome. While Chicago is not coastal, being a graduate student in the Committee on Evolutionary Biology has provided me with amazing opportunities to conduct field and lab research in marine ecosystems.