Central American Seaway (IMAGE) Smithsonian Tropical Research Institute Caption Before the Isthmus of Panama rose from the sea by tectonic and volcanic action, the Central American Seaway linked the Atlantic to the Pacific as one great ocean. Smithsonian researchers continue to debate when and how that happened. Credit Smithsonian Tropical Research Institute Usage Restrictions Credit STRI License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.