Investigation on the great Ordovician biodiversification event(GOBE):Review and prospect

The great ordovician biodiversification event(GOBE) is one of the major biotic revolutions in Early Paleozoic marine ecosystems. Through three internationally coordinated IGCP projects(IGCP 410, 503 and 591) in the past two decades, an enormous amount of paleontological, stratigraphical, paleoecological, and paleobiogeographical data have been accumulated, leading to a number of significant discoveries and common understandings regarding the GOBE. First, the multiple radiation pulses spanned nearly the entire Ordovician Period(more than 40 Ma), with several diversity acmes. Second, the biotic radiations were highly diachronous, characterized by different timing and rates in different regions. Third, the radiations were not associated with fundamental changes in the marine environments, but were rather controlled by both intrinsic factors(macroevolutionary regularities) and extrinsic forces(gradual environmental changes). Case studies conducted in South China have contributed greatly to the understanding of GOBE at the global scale. Future work on the GOBE includes more in-depth case studies to reveal the exact process and pattern of the radiations by combining systematic paleontology, high-resolution biostratigraphy, sedimentology, plate tectonics and geochemistry. This will help improve our understanding of the dynamics of the radiation and co-evolution between the organic and inorganic realms of Ordovician marine ecosystems.