About the Summons Group

We study organic matter from microbes, environmental samples, and rocks. Ancient rocks and oils contain a rich abundance of hidden information within, including molecular and isotopic signatures of the organisms that existed at the time the organic matter was formed. The goal of our research is to extract and interpret these signals, in order to reconstruct ancient environments and understand how life evolved within them.

Such interaction of the geosphere and the biosphere is how we define the field of geobiology. Through this study, we hope to obtain a better understanding of the timing and context of oxygenic photosynthesis (about 3 billion years ago), the conditions that led to the appearance of animal life on earth, and the causes of major mass extinction events. The techniques we develop might eventually help us detect signs of life on other planets, the science known as Astrobiology. Our lab is funded by the NASA Astrobiology Institute where we host the MIT Team.


Recent Publications

Waldbauer et al. 2011. Microaerobic steroid biosynthesis and the molecular fossil record of Archean life (PDF)

Kelly et al. 2011 Hydrocarbon biomarkers of Neoproterozoic to Lower Cambrian oils from eastern Siberia (PDF)

Summons et al. 2011. Preservation of Martian Organic and Environmental Records: Final Report of the Mars Biosignature Working Group (PDF)

Welander et al. 2010. Identification of a methylase required for 2-methylhopanoid production and implications for the interpretation of sedimentary hopanes

Welander et al. 2009. Hopanoids Play a Role in Membrane Integrity and pH Homeostasis in Rhodopseudomonas palustris TIE-1

Doughty et al. 2009. 2-Methylhopanoids are maximally produced in akinetes of Nostoc punctiforme: geobiological implications

Bradley et al., 2009. Extraordinary 13C enrichment of diether lipids at the Lost City Hydrothermal Field indicates a carbon-limited ecosystem. (PDF)

Grosjean et al., 2009. Origin of petroleum in the Neoproterozoic–Cambrian South Oman Salt Basin. (PDF)

Love et al., 2009. Fossil steroids record the appearance of Demospongiae during the Cryogenian period. (PDF)

Waldbauer et al., 2009. Late Archean molecular fossils from the Transvaal Supergroup record the antiquity of microbial diversity and aerobiosis. (PDF)