New fossil discoveries are forcing scientists to redraw the boundaries of ancient oceans, suggesting that some of the most ...

The open ocean has always made room for imagination. For centuries, sailors swore they saw monsters bigger than ships, smarter than people, and hungry enough to pull a crew straight off the deck. No ...

The historian Procopius described how a creature called Porphyrios terrified sixth-century sailors for 50 years. But what was it? A sixth-century Byzantine mosaic depicts an amphibious monster—though ...