Paleobotany traces its origins to the mid-nineteenth century, but at the beginning of the twenty-first century data from fossil plants have never been more relevant to understanding large scale patterns of plant evolution. Part of this renaissance has been fuelled by advances in paleobotany that have emphasised thorough integration of paleobotanical data with information from living plants. The relevance of paleobotanical data has also been greatly facilitated by renewed interest in plant phylogeny and the application of cladistic methods to both living and fossil taxa. Placed in a phylogenetic context paleobotanical data significantly expand our sample of plant diversity in time and space, and also provide a basis for beginning to understand the origins of modern plant diversity by calibrating rates of diversification. An integrated phylogenetic and paleobotanical approach to investigating plant diversification is also of great importance for understanding the origin of modern biogeographic patterns, and this is likely to be a major focus of research on plant diversity in coming decades.

Key words: biogeography, diversity, paleobotany, phylogeny