1. Department of Land Resources and Environmental Sciences Montana State University Bozeman MT USA
2. Departamento Científico Instituto Antártico Chileno (INACH) Punta Arenas Chile
3. Now at Center for Geomicrobiology, Department of Bioscience Aarhus University Aarhus C Denmark
4. Now at Flathead Lake Biological Station University of Montana Polson MT USA
5. Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA