MIT EAPS Directory

Gregory Fournier

Associate Professor of Geobiology

Greg Fournier is an expert in molecular phylogenetics, inferring the evolutionary histories of genes and genomes within microbial lineages across geological timescales, specifically, the complex histories of genes involved in “horizontal gene transfer” or HGT.

His research accomplishments span many eras of Earth’s history, including the identification of the HGT origin of acetoclastic methanogenesis at a time closely linked with the Permian-Triassic mass extinction, discovering genomic clues showing oxygen-dependent sterol biosynthesis evolved in the ancestors of eukaryotes over 2 billion years ago, and inferring some of the earliest events in the evolution of life on earth from ancient gene duplication and transfer events and sequence reconstruction, including the origin of the genetic code itself. Looking forward, his research objectives include (1) the HGT-based time calibration linking events in microbial metabolism evolution to global biogeochemical changes in the oxygen, carbon, nitrogen, and sulfur cycles; (2) reconstruction of the evolutionary origins of eukaryotes; and (3) extracting the complex, ancient histories of genes having undergone recombining HGT events that obscure their true ancestries.

Fournier received an A.B. degree in Genetics from Dartmouth (2001) and a Ph.D. in Genetics and Genomics from the University of Connecticut (2009). Since then he has worked as a Postdoctoral Associate at the University of Connecticut and – in the past 4 years – as a Postdoc in MIT’s Biological Engineering Department. He joined the faculty at MIT in 2014.


Fournier, G.P. and Alm E.J. (2015), Ancestral Reconstruction of a Pre-LUCA Aminoacyl-tRNA Synthetase Ancestor Supports the Late Addition of Trp to the Genetic Code, J Mol Evol. 2015 Apr;80(3-4):171-85. doi: 10.1007/s00239-015-9672-1. 

Gregory P Fournier, Cheryl P Andam and Johann Peter Gogarten (2015), Ancient horizontal gene transfer and the last common ancestors, BMC Evolutionary Biology, 201515:70, doi: 10.1186/s12862-015-0350-0




Young Investigator Selected Talk: American Society of Microbiology 112th General Meeting, San Francisco (2012) | Sherwood Change Award for Student Excellence in the Origin of Life: Gordon Research Conference on Origin of Life, California (2008)