Ancient Microbial Communities - Sumner's research includes understanding microbial evolution and ecology, and Earth history, through understanding microbial signatures in the rock record. Her publications feature new developments in how to interpret ancient biological responses to environmental factors, tracing oxygenation and the impact on carbonate microbial biological signatures.
Antarctic Lakes Sumner's research utilizes Antarctic lakes as a model system for understanding microbial processes, early oxygenic photosynthesis, and life on other planets. This work includes the discovery of pinnacles of microbial growth under ice-covered lakes and describes multiple microbial communities involved in the development of these features. Similar features in another Antarctic lake appear to record changes in the lake environment, including sea level, through time.
Exploration of Mars and its Environments Professor Sumner's research with the Mars Science Laboratory has generated over three dozen collaborative publications. Sumner's research has established that parts of ancient Mars could have hosted life as we know it on Earth, and contributed to the discovery of organic molecules on Mars. Sumner is a MSL “long term planner”, one of several lead geoscientists amongst more than five hundred scientists not directly employed by NASA on this project. She is also involved in future planning for additional Mars exploration, including a mission in 2020.
Awards and honors
Sumner was elected a Fellow of the Geological Society of America in 2014. Also in 2014, she was selected to deliver the honorary Carl Sagan Lecture at the American Geophysical Union. In 2016, Sumner was awarded the Career Award for Outstanding Contributions in Geosciences, Geobiology and Microbiology from the Geological Society of America.
Sumner is the author of a widely used anti-harassment statement that she made public so that other universities and institutes could use it as a model. A leader in helping institutions develop anti-harassment plans, Sumner presented to a workshop at the 2016 American Geophysical Union on “Addressing harassment and improving workplace climate.” She was also an invited presenter for Association of Polar Early Career Scientists webinar on sexual harassment during fieldwork.
Selected publications
Were kinetics of Archean calcium carbonate precipitation related to oxygen concentration? Geology, v. 24, p. 119-122. DOI: Sumner, Dawn Y. and John P. Grotzinger, 1996.
Late Archean calcite-microbe interactions: Two morphologically distinct microbial communities that affected calcite nucleation differently. Palaios, v. 12, p. 300-316. DOI: , Sumner, Dawn Y., 1997.
,inCarbonate Sedimentation and Diagenesis in the Evolving Precambrian World, J. Grotzinger and N. James, editors, S.E.P.M. Special Publication #67, p. 123-144. Sumner, Dawn Y. and John P. Grotzinger, 2000.
Renalcids as fossilized biofilm clusters. Palaios, v. 17, p. 225-236. DOI:, Stephens, Nat P. and Sumner, Dawn Y., 2002.
Cracks and fins in sulfate sand: Evidence for recent mineral-atmospheric water cycling in Meridiani Planum outcrops? Geology, v. 34, p. 229-232. DOI: . Chavdarian, Gregory V., and Sumner, Dawn Y. 2006.
Isotopic fingerprints of microbial respiration in aragonite from Bahamian stromatolites. Geology, v. 34, p. 973-976. DOI . Andres., Dawn Y. Sumner, et al. 2006.
Undirected motility of filamentous cyanobacteria produces reticulate mats. Geobiology, v. 8, p. 179-190. DOI: Shepard, Rebekah N., and Sumner, Dawn Y., 2010.
Discovery of large conical stromatolites in Lake Untersee, Antarctica. Geobiology, v.9. 280–293. DOI: Andersen, Dale T., Sumner, Dawn Y., et al., 2011.
Origins of Microbial Microstructures In the Neoproterozoic Beck Spring Dolomite: Variations In Microbial Community and Timing of Lithification.Journal of Sedimentary Research, v. 82, p. 709-722, DOI: . Harwood, Cara L., and Sumner, Dawn Y., 2012.
Antarctic microbial mats: A modern analog for Archean lacustrine oxygen oases. Geology, v. 43, p. 887-890. DOI: . Sumner, Dawn Y., Hawes, Ian, et al., 2015.
Growth of elaborate microbial pinnacles in Lake Vanda, Antarctica. Geobiology, v. 14, p. 556-574. DOI: . Sumner, Dawn Y., Anne D. Jungblut, et al., 2016.
A habitable fluvio-lacustrine environment at Yellowknife Bay, Gale Crater, Mars. Science, v. 343, 1242777. DOI: , Grotzinger, J.P., D.Y. Sumner, et al., 2014.
Outreach
Sumner has presented lectures to public and school groups, and she has participated in videos and films on exploring Mars. These have included presentations at Sierra College, a Northern California Rotary Club, and Sacramento State University's Science in the River City. She appeared in several videos on Mars exploration, including ones hosted by UC Davis and in the Finnish documentary film “The Other Side of Mars”. Dawn Sumner's research has been covered in local and national media outlets, including Popular Science, Wired Magazine, KPCC public radio, the television series Take Part, and the BBC.
