The world’s oceans have always been a source of both wonder and dread, inspiring countless tales of monstrous creatures lurking beneath the waves. For centuries, terrifying legends of colossal beasts and half-human entities were passed down by sailors, their imaginations fueled by fear and misidentification. These ancient myths, once accepted as fact, often arose from misidentification and exaggeration of real, extraordinary marine life. Modern science has revealed the actual animals that inspired some of the most enduring stories in maritime folklore.
Mermaids and the Gentle Giants
The enduring myth of the mermaid, or the dangerous siren, speaks of a beautiful half-woman, half-fish creature. The scientific name for the order of marine mammals known as “sea cows” is Sirenia, a direct nod to the mythological figures they are believed to have inspired. The manatee and the dugong, both gentle, slow-moving herbivores, are the likely candidates for these mistaken sightings.
These mammals often rise to the surface to breathe. The female’s mammary glands are located near her forelimbs, which could easily be mistaken for the breasts of a human nursing a calf. The manatee’s paddle-like tail, or the dugong’s fluked, dolphin-like tail, completed the illusion of a humanoid torso transitioning into a fish-like lower half. Even famed explorer Christopher Columbus recorded seeing “mermaids” on his voyages, noting they were “not so beautiful as they are painted.”
The Kraken and the Deep-Sea Predator
The legend of the Kraken describes a gargantuan, tentacled monster from the deep, capable of crushing the hull of a ship. This terrifying myth is rooted in the existence of the giant squid, Architeuthis dux, and its bulkier relative, the colossal squid. The giant squid is one of the largest invertebrates on Earth, with specimens having been reliably measured up to 43 feet long, including its two feeding tentacles.
The colossal squid (Mesonychoteuthis hamiltoni) is the heavyweight, with an estimated maximum weight of up to 1,500 pounds. Furthermore, the colossal squid’s tentacles are armed with rotating, razor-sharp hooks instead of simple suckers. The discovery of massive squid carcasses washed ashore, or the observation of their enormous eyes—the largest in the animal kingdom—provided a factual basis for the stories of a monstrous, many-armed predator.
Sea Serpents and the Ribbon Fish
The sea serpent is consistently described as a massive, elongated, snake-like creature, sometimes adorned with a mane or crest. The real-life inspiration for this myth is the oarfish, specifically the giant oarfish (Regalecus glesne), the world’s longest bony fish. This deep-sea dweller possesses a silver, ribbon-like body and can reach lengths of over 36 feet.
The oarfish has a striking, bright red dorsal fin that runs the entire length of its body, with the first few rays forming a distinctive, crown-like crest on its head. It rarely comes to the surface, usually only when sick, injured, or dying. When glimpsed briefly or found washed ashore, its immense, serpentine form and crest could easily be interpreted by early mariners as a serpent of the abyss.
Unicorns of the Sea
The myth of the unicorn, a creature of purity whose horn held magical healing and poison-detecting properties, has a surprising marine counterpart: the narwhal. The narwhal (Monodon monoceros) is an Arctic whale whose most distinguishing feature is a single, spiraled tusk that projects from its head, sometimes reaching over nine feet in length. This tusk is actually an elongated canine tooth, found primarily in males.
During the Middle Ages, Viking traders brought these tusks to Europe, selling them for exorbitant sums as the genuine horns of the mythical unicorn. The rarity and exotic origin of the tusk allowed the deception to persist, making the narwhal’s ivory one of the most valuable commodities. The narwhal’s tusk was successfully marketed as physical proof that the magical creature existed, albeit in the icy northern seas.