Timeline of ceratosaur research

This timeline of ceratosaur research is a chronological listing of events in the history of paleontology focused on the ceratosaurs, a group of relatively primitive, often horned, predatory theropod dinosaurs that became the apex predators of the southern hemisphere during the Late Cretaceous. The nature and taxonomic composition of the Ceratosauria has been controversial since the group was first distinguished in the late . In 1884 Othniel Charles Marsh described the new genus and species Ceratosaurus nasicornis from the Late Jurassic Morrison Formation of the western United States. He felt that it belonged in a new family that he called the Ceratosauridae. He created the new taxon Ceratosauria to include both the Ceratosauridae and the ostrich-like ornithomimids. The idea of the Ceratosauria was soon contested, however. Later that same decade both Lydekker and Marsh's hated rival Edward Drinker Cope argued that the taxon was invalid. The idea of the Ceratosauria would regain some support more than thirty years later when Gilmore argued in its favor in 1920. Nevertheless, the validity of Ceratosauria was disputed throughout much of the by researchers like Romer, Lapparent, Lavocat, Colbert, and Charig. However, in 1986, more than a century after Marsh first coined the name, Jacques Gauthier revived the idea. Three years later, Rowe published a new definition of Ceratosauria, all taxa more closely related to Ceratosaurus than to birds, based on Gauthier's use of the term. This modern use of the term was thought to include the many theropods discovered since the known as coelophysoids. Ceratosaurus itself had loose joints between bones in the skull whose interpretation has been controversial. Paleontologist Robert T. Bakker has interpreted this condition as an adaptation to swallow prey larger than it would otherwise be able to fit through its jaws. Since the , major developments in ceratosaur taxonomy have centered on the discovery of the Abelisauridae, a new family of large ceratosaurs that were among the dominant predators of the southern hemisphere during the Cretaceous.