Most if not all of the pictures and artwork I've seen show cloven hooves on the unicorn so they are supposedly not related to horses. They definitely lived not too long ago but what were they exactly? More like antelopes or goats I guess but their body shapes most often look like horses though...
The thing is that these purposely "elongated" skulls created by keeping babies in baby racks, so to speak, made skulls flat on the back. They did not create this kind of "elongation." Many babies naturally develop mis-shapen skulls if they always lay to one side or the other all the time. You...