In novels like “Moby Dick” or “20,000 Leagues Under the Sea,” monsters exist to aggravate and impinge on human life. Science, folklore, and fiction have villainized deep sea creatures for centuries, ...

These real-life ocean animals were so terrifying to seafarers that they became embedded in history as legendary sea monsters ...

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 ...