Dating the time of origin of major clades
There is a long-standing debate on the extent of vicariance and long-distance dispersal events to explain the current distribution of organisms, especially in those with small diaspores potentially prone to long-distance dispersal.Age estimates of clades play a crucial role in evaluating the impact of these processes.
The parmelioid group diversified around the K/T boundary, and the major clades diverged during the Eocene and Oligocene. uri=info:doi/10.1371/0028161&representation=PDF Guillermo Amo de Paz, Paloma Cubas, Pradeep K. The radiation of the genera occurred through globally changing climatic condition of the early Oligocene, Miocene and early Pliocene. Zachos J , Pagani M , Sloan L , Thomas E , Billups K ( 2001 ) Trends, rhythms, and aberrations in global climate 65 Ma to present . The estimated divergence times are consistent with long-distance dispersal events being the major factor to explain the biogeographical distribution patterns of Southern Hemisphere parmelioids, especially for Africa-Australia disjunctions, because the sequential break-up of Gondwana started much earlier than the origin of these clades. Sanmartn I , Ronquist F ( 2004 ) Southern Hemisphere biogeography inferred by event-based models: plant versus animal patterns . However, our data cannot reject vicariance to explain South America-Australia disjunctions. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a PDF plug-in installed and enabled in your browser. Alternatively, you can download the file locally and open with any standalone PDF reader: Object.action?