Christopher J. Cleal is Head of Botany at the National Museum Wales. He is a Fellow of the Geological Society, London, and the Linnean Society, London, and is a member of the Fossil Plant Committee of the International Association of Plant Taxonomy (IAPT). He has published nine books and over 200 papers in academic journals, dealing with palaeobotany, stratigraphy and geoconservation. Barry A. Thomas is an Honorary Professor and a Lifelong Learning Lecturer at Aberystwyth University and is a Research Fellow at the National Museum Wales.
Previously, he was Head of Life Sciences and Dean of the Faculty of Science and Mathematics at Goldsmiths, University of London and Keeper of Botany at the National Museum Wales. He has published and edited 28 books and has over 180 papers in academic journals, dealing with palaeobotany, geoconservation and living plants.