Ancient global change, extreme climate transitions, and related biostratigraphy, (paleo)ecology, (palaeo) provincialism, biochemistry, etc. of phytoplankton, and of (organic walled) dinoflagellate(s) (cysts) in particular. (Co-)author of >125 peer reviewed international papers, (co)-supervisor of >50 MSc theses, and >20 PhD theses, Utrecht University and elsewhere. Co-chief, shipboard, and postcruise participant of many (I)ODP legs, incl. ACEX, the Arctic Drilling Expedition,and IODP Expedition 318, Wilkes Land, Antarctica.

Many NWO and ESF grants; Combined NWO- UU nomination, and final, The
Netherlands Science and Society award 2007, Academic Outreach UU Team Prize
winner 2006/2007 (‘Academische Jaarprijs’).