Overview

• Paleontologists identified Ontocetus posti from fossils in the UK and Belgium.
• The species shares feeding adaptations with modern walruses, indicating convergent evolution.
• Ontocetus posti's anatomy suggests it was adapted to suction-feeding.
• The species migrated from the North Pacific to the Atlantic via the Central American Seaway.
• Global cooling in the Late Pliocene likely led to the extinction of Ontocetus posti.