The existence of the fabled animal and the reason it is Scotland's national animal have been the subject of some speculation since archaeologists discovered what might be a fossil of an ancient unicorn in a remote area of the Scottish Highland.
The fossils seem to be mostly unaltered, though some may have had their spiraled horns lost or removed.
Since more excavations are anticipated in the area, the find's precise location has not yet been made public.
The Unicorn
Since antiquity, the unicorn has been depicted as a mythical animal with a single, enormous, pointed, spiraling horn sticking out of its forehead.
Ancient Indus Valley Civilization seals featured unicorns, and Greek natural history writers also made mention of unicorns in their writings.
The re'em, which some editions translate as a unicorn, is another animal that the Bible mentions.
One of Scotland's national animals, unicorns has a long history of being connected to Scottish history. In recognition of this, a unicorn is depicted on the United Kingdom's royal coat of arms.
Although there are no solid, conclusive records or evidence, there has been speculation about why this animal is so prominent in Scottish history and why the unicorn is Scotland's national animal.
Recent reports of the remains of all other unicorn species have raised the possibility that the extinct status of unicorns is much shorter than previously thought.
The ancient unicorn fossil was later determined to be a Siberian unicorn, Knowing Daily reported.
Siberian Unicorn
Only five rhinoceros species still exist today, but there were once as many as 250 different species, according to the Natural History Museum.
Elasmotherium sibiricum was among them, and it was one of the most impressive.
It lived on the grasslands of Eurasia, from western Ukraine and Russia to Kazakhstan and Siberia, and could weigh up to 3.5 tonnes.
The species eventually perished, though the exact time has been disputed.
One of the most important occurrences during that time for those researching the last Ice Age fauna was the extinction of the megafauna.
Many enormous, well-known species, including the woolly mammoth, the saber-toothed cat, and the Irish elk, went extinct during this time.
Read also: US and UK Museum Officials Decode the 'Origins' of Unicorn Myth
Adrian Lister, a professor and Merit Researcher from the Museum, explained that after about 40,000 years, this megafaunal extinction event began to take place.
Elasmotherium, which appears to have gone extinct 100,000 years ago, has not been included in the same event.
However, there have been some indications in recent years that this previously believed extinction date for E. sibiricum may not be accurate.
Lister said that to their surprise when they carbon dated a few specimens-including the exquisite complete skull on display at the Museum-they discovered that they were less than 40,000 years old.
This didn't mean much on its own, but by collaborating with Dutch and Russian researchers, several more fossils were analyzed.
The researchers eventually had 23 dated specimens after starting with no radiocarbon-dated Elasmotherium fossils at all.
Lister said that they all strongly agreed that this species continued to exist until around 39,000 years ago and possibly as recently as 35,000 years ago.
Their research on the ancient unicorn species was published in the journal Nature Ecology & Evolution.
Related article: Siberian Unicorn: Massive Real-Life Unicorn That Walked the Earth 35,000 Years Ago