The study will examine radiolarian lineages and their speciations in high and low latitudes to answer the following questions: 1) Where and when did each speciation take place? 2) If branchings have occurred in both regions, is the evolutionary pattern of speciations and anagenetic change the same? Are the rates different in high and low latitudes? 3) How can evolutionary appearance best be differentiated from migrational appearance of species in different latitudes? How can this be reflected in a taxonomic framework? Integration of existing biostratigraphies and taxonomies in the different regions will be a byproduct of answering the above questions. The study will provide fundamental insights into the nature of evolutionary processes in marine plankton.
