Nigel Trewin is a Professor of Geology at the University of Aberdeen. His research has focussed on ancient environments and ecosystems, particularly the Devonian Old Red Sandstone of Scotland, including the prolific fossil fish beds, and the early terrestrial biota of the Rhynie chert. He edited the definitive work The Geology of Scotland (4th Edition, London, 2002). At Aberdeen University he has taught geology and led field excursions for students, industry and non-specialists for nearly forty years.