Are Unicorns Real? Proof, Theories and Lore

The lore surrounding unicorns is rich and diverse, with variations found in cultures worldwide. In Western mythology, unicorns are often depicted as horselike creatures with only one horn on their foreheads. They are symbols of purity, grace and rarity, believed to be elusive and magical beings. In some legends, only virgins could tame or approach unicorns.

In various cultures, the unicorn's horn, often called an alicorn, was believed to possess magical powers of healing and the ability to neutralize poisons. Unicorns have been associated with the divine and were considered symbols of Christ in medieval Christian symbolism.

Unicorns have appeared in stories from ancient China to medieval Europe, symbolizing everything from strength and courage to innocence and harmony with nature. The creatures are sometimes linked to rainbows, considered a manifestation of their ethereal essence. This connection underscores their role as bridge-builders between realms, where the mundane and the magical intertwine.

As "pretty horses" adorned with a single, spiraled horn, they traverse not just the terrestrial landscapes. For example, encountering a unicorn in a dream may signify a desire for a sense of wonder or a connection to one's inner child.

Aside from good vibes, bridging worlds and evoking wonder, the creature's magical essence often derives from its horn. Outside of magical healing properties, there are many other theories about the creature's standout feature.

As Argentinian writer and dreamer Jorge Luis Borges pointed out, "The first version of the unicorn is nearly identical with the latest." In other words, the unicorn is rarely more than a one-horned horse.

As Joe McCormick and I discuss in our podcast episode "Unicorns of the Mythic World," the fairy-tale beast has come to symbolize everything from sinful lust to Jesus Christ himself — but the purpose of its single horn is rarely clear. Luckily, our episode provides some tantalizing biological suggestions as to why these fanciful beasts would boast such a fabulous protrusion.

For starters, we can cast aside the more magical properties. Natural world organisms don't purify lakes or heal wounded paladins with their bony growths. It's also tempting to cast aside the notion presented in Ridley Scott's 1985 film "Legend," that a unicorn's horn is "a single horn reaching straight to heaven," as if it functions as a sort of divine antenna.

Yet, the idea of a horn antenna isn't that far-fetched.

The most famous real-life unicorn of the natural world is the narwhal (Monodon monoceros), a marine animal with a single tusk that dwells in the Arctic. But this tusk does not possess any magical traits; it's actually an oversized canine tooth that grows straight out of the creature's face.

The exact purpose of the tusk remains a topic of scientific dispute, but it might well function as a sense organ since it's loaded with sensitive nerve endings. Some researchers theorize that narwhals use the tusk to focus their potent echolocation powers, which they use to hunt fish, shrimp and squid.

Martin Nweeia of Harvard's School of Dental Medicine also suggests that it may be used to detect changes in water salinity. Still, sensory explanations for narwhal tusks are undercut by the fact that females rarely grow them. As in most cases of sexual dimorphism, we can usually assume that mating plays a key role in the difference.

This brings us back to the mythical creature known as the unicorn.

Mating or Self-Defense?

Perhaps only the males of the species boast horns as a means of sparring with romantic rivals or communicating sexual fitness to potential mates. The latter reason, at least, would jibe with the writings of fifth-century B.C.E. Greek historian Ctesias, in which the unicorn's horn is red, black and white, which sounds an awful lot like a festive mating display.

The other obvious possibility is that they provide a means for the unicorn to defend itself against predators, such as human hunters or its legendary rival, the lion. This at least matches up with one of the creature's most closely associated real-world counterpart: the rhinoceros.

The unicorns of medieval European art were a docile-looking bunch, but older texts described a more fearsome creature. First-century Roman author Pliny the Elder wrote that a unicorn could not be taken alive, and others depicted it as a creature capable of besting lions. Sometimes, it would seem, the most violently obvious guess is the most valid.

At one point in time, unicorns really did exist — but they weren't the magical, glittery ones that can be found on the covers of Lisa Frank notebooks or bedtime stories for children. According to scientists, these very real animals, known as Siberian unicorns, reportedly roamed around Western Siberia thousands of years ago.

Also known as Elasmotherium sibiricum, the Siberian unicorn presents a fascinating contrast to the conventional unicorn of mythology. Unlike the single-horned horse-like creatures often depicted, the Siberian unicorn was a real prehistoric mammal resembling a rhino.

Before lovers of cute one-horned white horses celebrate, there is a bit of bad news to process: These real-life unicorns looked nothing like their mystical counterparts. The creatures weighed up to two times as much as rhinos and had protruding humps on their shoulders.

Scientists previously thought that this prehistoric creature lived during the late Pliocene to the early Pleistocene epoch, which spans from around 2.6 million to 200,000 years ago. However, more recent research and fossil evidence suggest that these real unicorns actually existed more recently, with some estimates placing its existence between 35,000 and 39,000 years ago.

The rhino-looking unicorn ultimately faced extinction due to a combination of factors, including changing climate conditions and shifts in vegetation. As the environment altered, its grazing habitats diminished, and it struggled to adapt. Despite its robust size and unique horn, the pressures of a transforming ecosystem led to its eventual disappearance from the Earth.

This article was updated in conjunction with AI technology, then fact-checked and edited by a HowStuffWorks editor.