The phytogeography of the Northern Hemisphere represents one of the great challenges to understanding the interaction of Earth history and biological diversification. Although floristic similarities between the disjunct areas of Laurasia are striking, it has become increasingly clear that phylogenetic hypotheses are needed to resolve the dynamic history of vicariance throughout the Cretaceous and Tertiary. One of the major advances towards further understanding phytogeographic connections around the Northern Hemisphere has been the significant increase in the number of phylogenies for disjunct taxa. By the summer of 2000 phylogenies for as many as 70 relevant taxa will be available for consideration, allowing the search for general patterns in area cladograms. The goals of this symposium are: 1) to assemble and help coordinate the activities of investigators working from various perspectives on reconstructing angiosperm distributions around the Northern Hemisphere; 2) to explore the use of modern methods in analytical biogeography in synthesizing knowledge of geographic patterns around the Northern Hemisphere; and 3) to evaluate phylogenetic hypotheses for temporal congruence in the context of fossil data and current theories regarding geological and climatic changes.

Key words: analytical biogeography, angiosperms, Northern Hemisphere, phytogeography