Diploma in Zoology, University of Basle, 1974.
M.Sc., Vertebrate Paleontology, University College London, 1975.
Ph.D., Zoology, University of Basle, 1978.

Foreign Member of the Linnean Society of London, 1992.
Council, Society of Systematic Biologists, 1994.
Associate Editor, Journal of Vertebrate Paleontology, 1993-1995.
Associate Editor, Zoological Journal of the Linnean Society, 1992-present.
Society of Vertebrate Paleontology: Romer Prize Committee, 1993-present; Honorary Membership Committee, 1993-present.

My research concentrates on the analysis of phylogenetic relationships of marine Mesozoic reptiles; I am currently involved in a global revision of the Triassic stem-group Sauropterygia. Having completed the revision of Sauropterygia from the Germanic and Alpine Triassic (western Tethyan province), I am now moving towards the analysis of Triassic Sauropterygia from Israel and China (eastern Tethyan Province). From this systematic work emerge most interesting patterns of dispersal and diversification of stem-group Sauropterygia in correlation with the development of the Tethyan sea. The analysis of phylogenetic relationships of Sauropterygia within the reptiles as a whole has produced highly unconventional results with respect to the placement of turtles, and thus opened long-standing problems of higher level relationships within Reptilia. A field program in the marine Middle Triassic of the western United States targets the collection of marine Triassic reptiles in northwestern Nevada and more recently, in Wyoming.