I am a plant biologist and paleontologist interested primarily in the diversity and evolutionary history of plant life. A major component of my work has been the careful comparison of fossil plants with their living relatives to understand how different groups of plants are interrelated and have changed through time. A particular focus has been the study of exquisitely preserved fossil flowers and understanding their relevance for interpreting the diversification of flowering plants, which today are the most diverse of all groups of plants, with more than 300,000 living species. I have also worked on the initial colonization of the land by plants as they made the transition from a purely aquatic to land-based existence. My current interests focus on large-scale patterns in the history and diversity of living plants. Through directing the science programs at the Royal Botanic Gardens, Kew, in the United Kingdom I am also increasingly concerned with how plant diversity can best be conserved for the future and how it can be used in sustainable ways for human benefit.