Abstract Detail
Systematics Section / ASPT Hardy, Chris R. [1], Linder, H. Peter [1], Moline, Philip M. [1]. On the origin and rates of cladogenesis in the African Restionaceae (Cape Floristic Region, southern Africa)
(Cape Floristic Region, southe. The African Restionaceae comprise some 350 species and constitute a characteristic and ecologically dominant element of the vegetation in the species-rich Cape Floristic Region of southern Africa. Applying fossil evidence and various molecular-clock-based techniques in a phylogenetic study of more than 300 of these species indicates that the radiation of the African Restionaceae started in the early Oligocene or late Eocene, about 20 my earlier than the late Miocene dates that have been postulated by various researchers for the formation of the distinctive Cape flora in general. Similar investigations of other Cape clades reveal radiations ranging from 7 to 20 my in age. If extrapolation to the flora as a whole is appropriate at this time, the remarkably species-rich Cape flora is the product of a sustained accumulation of species (via speciation, lineage recruitment, and the lack of mass extinctions) since at least the early Oligocene.
1 - University of Zurich, Institute of Systematic Botany, Zurich, CH-8008, Switzerland
Keywords: rapid radiation speciation species richness Cape Floristic Region South Africa Restionaceae Poales.
Presentation Type: Paper Session: 43-19 Location: Cottonwood A (Snowbird Center) Date: Wednesday, August 4th, 2004 Time: 12:45 PM Abstract ID:433 |