Diatryma is a prehistoric bird species that lived during the Eocene epoch, approximately 56-34 million years ago. The species is also known as the "terror bird" due to its large size and fearsome appearance. Despite its scientific name, there are several synonyms for Diatryma, including Gastornis, Brontornis, and Titanis. These names were given to similar bird species that lived during different time periods and locations but shared similar characteristics with Diatryma. The study of these prehistoric birds provides valuable insights into the evolution of avian species and the diversity of life on Earth millions of years ago.