New scientific findings have the potential to produce considerable changes in previous interpretations. Vertebrates are not an exception. Based on information gathered over almost two centuries it has long been believed that the origin of vertebrates occurred "sometime" during the earliest Paleozoic, "somewhere" in the northern Hemisphere. However, discoveries of early vertebrates in the Southern Hemisphere (e.g., Australia and Bolivia) led to a new understanding of the early history of the group. These new discoveries have been remarkable in stimulating new collecting. Recent progress has included the discovery of the "earliest" forms in the Lower Cambrian of China together with new and controversial interpretations of the conodonts.