1 Institute of Arctic and Alpine Research, University of Colorado Boulder, CO, USA ; Environmental Studies Program, University of Colorado Boulder, CO, USA ; Department of Biology, Duke University Durham, NC, USA.
2 Department of Microbiology and Molecular Genetics, Michigan State University East Lansing, MI, USA.
3 CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE Montpellier, France.