Postdoctoral Associate

phone (608) 469 7590

Department of Earth, Atmospheric and Planetary Sciences
Massachusetts Institute of Technology
E54-1025, 77 Mass Ave
Cambridge, MA 02139



2016-present –Postdoctoral Associate, Department of Earth, Atmospheric and Planetary Sciences, MIT
2009-2016 – Ph.D., Department of Earth and Planetary Sciences, University of California-Davis
2009-2012 – M.S., Geology Department, University of California-Davis
2004-2008 – B.A., Geology Department, Carleton College


My research focuses on how evidence of microbial communities and their role in ecosystems can enter the rock record. To this end, I have three primary avenues of study: 1) assessing the role of microbial activity and depositional environment on distinctive microbial mat growth forms in modern settings, 2) investigating geochemical biosignature formation in mineralizing microbial ecosystems, 3) exploring specific facies where microbial communities could have produced geochemical microenvironments important to the evolution of multicellular life. In my postdoctoral work, I am characterizing shallow water depositional environments from Neoproterozoic strata of Svalbard to assess the importance of cold water habitats for early animals during the Marinoan Glaciation.

Select Publications

Mackey, TJ, Sumner, DY, Hawes, I, Jungblut, AD, Lawrence, J, Leidman, S, Allen, B (2017) Increased mud deposition reduces stromatolite complexity. Geology, DOI: 10.1130/G38890.1.

Sumner, DY, Jungblut, AD, Hawes, I, Andersen, DT, Mackey, TJ, Wall, K (2016 Growth of elaborate microbial pinnacles in Lake Vanda, Antarctica. Geobiology. DOI:10.1111/gbi.12188

Jungblut, AD, Hawes, I, Mackey, TJ, Krusor, M, Doran, P, Sumner, DY, Eisen, J, Hillman, C, Goroncy, A (2016) Microbial mat communities along an oxygen gradient in a perennially ice-covered Antarctic lake. Applied and Environmental Microbiology, 82(2): 620-630. DOI:10.1128/AEM.02699-15

Sumner, DY, Hawes, I, Mackey, TJ, Jungblut, AD, Doran, P (2015) Antarctic microbial mats: A modern analog for Archean lacustrine oxygen oases. Geology, 43: 887-890. DOI:10.1130/G36966.1

Mackey, TJ, Sumner DY, Hawes I, Jungblut AD, Andersen DT, (2015)  Growth of modern branched columnar stromatolites in Lake Joyce, Antarctica. Geobiology, 13: 373-390. DOI:10.1111/gbi.12138

Hawes, I, Sumner, DY, Andersen, DT, Jungblut, AD, Mackey, TJ (2013) Timescales of growth response of microbial mats to environmental change in an ice-covered Antarctic lake.  Biology, 2: 151-176. DOI:10.3390/biology2010151

Hawes, I, Sumner, DY, Andersen, DT, and Mackey, TJ (2011) Legacies of recent environmental change in the benthic communities of Lake Joyce, a perennially ice-covered Antarctic lake. Geobiology 9, 394-410. DOI: 10.1111/j.1472-4669.2011.00289.x