Is there any evidence that unicorns ever existed?

There is no fossil or photographic evidence that unicorns exist. Scientists have described rare cases of single, centrally located horns in deer and cattle, and Ringling Brothers and Barnum & Bailey Circus exhibited a surgically altered, one-horned goat in 1985.

Historians believe that the original concept of the unicorn as a single-horned, horselike or deerlike creature arose from travelers' descriptions of antelope, rhinoceros or extinct animals, such as the aurochs or elasmotherium. Pre-medieval artists generally presented their figures only in profile, making it impossible to tell if a pictured animal had one horn or two. Medieval merchants often sold narwhal tusks as unicorn horns for medicinal or protective purposes.