Yes, it would prove that there ARE unicorns. (And, in fact, there
are. It's a weird abnormality in goats, that the roots of their two
horns are very close together in the center of the forehead, so close
that the horns actually grow together; their being so close together
interferes with their growth pattern so they usually end up with
straighter horns than is normal for goats of their species -- this
has been seen in a couple different species. Very rare, only a few
cases known to have occurred, and AFAIK nobody has bought two and
tried to breed them so we don't know if the abnormality breeds true.
And of course, aside from the oddity of the horns, unicorns are
perfectly ordinary goats. Not immortal, not the good/evil beings of
various mythologies, not more intelligent than one would expect of a
goat, no odd magical properties, their horns don't cure illness or
injury, they don't have a thing about virgins -- or at least not
HUMAN virgins.)
It would NOT prove that there WERE unicorns in, say, classical Greek
times. (Not even one of those abnormal goats.)
> However, there is some rather hot debate about whether nanobacteria do
> exist or not. So if we could produce nanobacteria the question about
> their impossibility could at least be settled.
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