He gained his PhD from the University of Zürich in 1998 working on comparative floral structure of Acanthaceae. He then undertook post-doctoral work at the Swedish Museum of Natural History (palaeobotany), at the University of Zürich (molecular phylogenetics and floral evolution), and the University of Wisconsin-Madison (molecular phylogenetics). His research interests are in phylogenetic relationships and floral evolution of various groups of fossil and extant flowering plants. Recent work is focused on Ericales, Acanthaceae, and Platanaceae.