Newfound Ancient 'Sea Monster' Is Largest Yet from Antarctica

About 66 million years ago, an ancient sea monster the height of a five-story office building once gnashed its sharp teeth as it swam around the dark waters of Antarctica, a new study finds. The newfound beast, known as a mosasaur — a Cretaceous-age aquatic reptile that sped through the ancient seas using its paddle-like limbs and long tail — is only the second fossilized mosasaur skull ever found in Antarctica. Scientists with the Chilean Paleontological Expedition discovered the mo