Pete Girguis, Ph.D.

Harvard University


Ecological physiology of animal-microbial symbioses, adaptations to life in the deep sea, novel underwater sensors to study deep sea eco-physiology and biogeochemistry.

Pete Girguis, Ph.D.

Research Description

Symbioses – in particular microbial-animal symbioses – play a disproportionate role in shaping the ecology, evolution and biogeochemistry of many deep sea habitats. I study the metabolic interactions, and resulting ecological and biogeochemical implications, of animal-microbial symbioses, as well as the physiological/biochemical adaptations that support these symbiotic relationships. I also work to quantify how symbioses shape the geochemistry of their respective environments. To that end, I develop new underwater and laboratory-based tools that allow us to study symbioses (and free-living organisms) in their natural habitat, or in deep sea aquaria that mimic in situ conditions.

Research Impact

Through the development of these new technologies, my team has shown how host and symbiont metabolic capacities have co-evolved to support their partnership – such as how deep sea tubeworms have evolved an unprecedented ability to maintain their internal pH, which is critical to maintaining symbiont function. Our work has also shown that deep sea symbioses fix carbon at some of the highest rates ever measured on land or in sea. Currently, we are focused on linking molecular (gene/protein expression), ecological (niche partitioning), and biogeochemical processes to better understand how symbioses influence matter/energy flux in their communities and habitats.


related links

Science Symbiosis in Aquatic Systems Harvard University, Department of Organismic and Evolutionary Biology Back


  • B.Sc., Ecology and Marine Biology, University of California Los Angeles, USA
  • Ph.D., Ecology, Evolution, and Marine Biology, University of California Santa Barbara, USA
  • Postdoctoral study, Marine Microbiology, Monterey Bay Aquarium Research Institute, USA