Panama Canal (IMAGE) Smithsonian Tropical Research Institute Caption A cargo ship in the Panama Canal traverses volcanic rocks that helped form the Isthmus of Panama. Credit credit: Aaron O'Dea Usage Restrictions Credit: Aaron O'Dea 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.