Max Planck Institute for Marine Microbiology

Plant Biology, Michigan State University

Newcastle University, Newcastle upon Tyne

Professor, Zoology and Botany, University of British Columbia

Seoul National University, CJ Bioscience(ChunLab), Inc.

Curator of Lichenized Fungi and Vice President, Science, The Field Museum

National Center for Biotechnology Information, NLM, NIH

University of Tartu

Professor for Evolutionary Biology, Technische Universität Braunschweig

Senior Curator, Botanischer Garten und Botanisches Museum, Freie Universität Berlin