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Stephanie S. Porter


Field of Study: Evolutionary ecology, quantitative genetics, and genomics
Title: Assistant Research Professor
Degrees: Ph.D., University of California, Berkeley
Homepage: Homepage/Lab Web Site Link
Google Scholar:  Google Scholar
Office: 230J
Phone: (360) 546-9478
Mailing Address: School of Biological Sciences
Washington State University
PO Box 644236
Pullman,WA 99164-4236


Our lab combines evolutionary ecology, quantitative genetics, and genomics to study mutualisms and environmental adaptation. Understanding how symbiotic partners co-evolve and adapt to different environments is ecologically and agriculturally important. For example, this will help us explain how cooperation is maintained in the symbiosis between plants and rhizobium bacteria, which is responsible for half of all current biologically fixed terrestrial nitrogen. In this symbiosis, host plants trade photosynthetically derived carbon for nitrogen fixed by endosymbiotic rhizobium bacteria housed in root nodules.

Representative Publications:

  • Jack CN, Wozniak K, Porter SS, Friesen ML (2018) Rhizobia Protect Their Legume Hosts Against Soil-Borne Microbial Antagonists in a Host-Genotype-Dependent Manner, Rhizosphere, 9:47-555, DOI: 10.1016/j.rhisph.2018.11.005 JackEtAl2018
  • Helliwell E, Faber-Hammond J, Lopez Z, Garoutte A, von Wettberg E, Friesen M, Porter SS (2018) Rapid establishment of a flowering cline in Medicago polymorpha after invasion of North America, Molecular Ecology, DOI: 10.1111/mec.148 HelliwellEtAl2018
  • Porter SS, Faber-Hammond J, Montoya A, Friesen ML, Sackos C (2018) Dynamic genomic architecture of cooperation in a wild population of Mesorhizobium, ISME J PorterEtAl2018
  • Calisi RM, A Working Group of Mothers in Science (2018) How to tackle the childcare-conference conundrum, PNAS CalisiEtAl2018 or
  • Porter SS, Faber-Hammond JJ, Friesen ML (2018) Co-invading symbiotic mutualists of Medicago polymorpha retain high ancestral diversity and contain diverse accessory genomes, FEMS Microbial Ecology PorterEtAl2018
  • La Pierre KJ, Simms EL, Tariq M, Zafar M, Porter SS (2017) Invasive legumes can associate with many mutualists of native legumes, but usually do not, Ecology and Evolution, DOI: 10.1002/ece3.3310 LaPierreEtAl2017
  • Amsellem L, Brouat C, Duron O, Porter SS, Vilcinskas A, Facon B (2017) Importance of microorganisms to macroorganisms invasions — Is the essential invisible to the eye? Advances in Ecological Research (Special Issue on Networks of Invasion) AmsellemEtAl2016
  • Porter SS, Chang PL , Conow CA, Dunham JP, Friesen ML (2017) Association mapping reveals novel serpentine adaptation gene clusters in a population of symbiotic Mesorhizobium, ISME, doi: 10.1038/ismej.2016.88 PorterEtAl2016
  • Briscoe Runquist R, Grossenbacher D, Porter SS, Kay K, Smith J (2016) Pollinator-mediated assemblage processes in California wildflowers, Journal of Experimental Biology, doi: 10.1111/jeb.12845 RunquistEtAl2016
  • Jones EI, Afkhami ME, Akcay E, Bronstein JL, Bshary R, Frederickson ME, Heath KD, Hoeksema J, Ness J, Pankey S, Porter SS, Sachs JL, Scharnagl K, & Friesen ML (2015) Cheaters must prosper: reconciling theoretical and empirical perspectives on cheating in mutualism. Ecology Letters, 18(11):1270-1284. JonesEtAl2015