Dawn Y. Sumner

Dawn in Pearse Valley, Antarctica

I am a geobiologist who explores complex interactions among environments and life across geological time. My lab group traces the history of Earth-life interactions through their impacts on evolution and environmental conditions. These investigations are highly collaborative, building on diverse ideas from creative individuals using techniques from stratigraphy, genomics, petrography, biogeochemistry, ecology, and more. CV (April 2020)

(This site is new and is being updated incomplete and stalled…at about the rate of a medium speed gliding cyanobacterium that lacks light.)


Some of our active projects include:

  • Characterizing microbial communities in ice-covered lakes, Antarctica (details)
    • Organisms basal to previously known O2 producing cyanobacteria, including Melainabacteria and Aurora (led by Christy Grettenberger)
    • The seasonal dynamics of “O2 oasis” created by photosynthesis in Lake Fryxell microbial mats (newly funded; Jessica Mizzi and Sydney Salley)
    • Relationships among microbial mat morphology, microbial communities, and environmental gradients, including nutrient cycling (Sydney Salley and Jessica Mizzi)
  • Reconstructing microbial communities and their geochemical environments prior to the Great Oxidation Event (details)
    • Pyritic interval associated with a meteorite impact (Emilia Hernandez)
    • Primary productivity in fenestrate microbialites from South Africa (Sydney Salley)
  • Exploring Mars with Curiosity (the rover) (details)
    • Ancient environmental and diagenetic conditions in Gale Crater, Mars
    • Habitability of martian environments

(Sumner’s publications on Scholar)


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