Place: 4274 Chamberlin (refreshments will be served)
Speaker: Tom Givnish, UW Department of Botany
Abstract: Orchids are the most diverse family of angiosperms, with more species than mammals, birds, and reptiles combined. Many ideas have been advanced to account for their extraordinary diversity, but they have – until quite recently – been impossible to test because we lacked a good phylogeny (family tree) for the orchids. My colleagues and I have now developed a well-resolved phylogeny for the orchids, based on large numbers of chloroplast genes, and I will show how we can use this phylogeny to identify the age and place of origin of the orchids, assess the role of different orchid traits in driving high rates of speciation, and reconstruct the geographic spread of orchids across the planet. I will also describe some of the remarkable aspects of the ecology of this endlessly fascinating group that have recently come to light, mention some of the notable aspects of orchid diversity in Wisconsin, and sketch some interesting scientific and conservation issues that should be explored in the future.