This makes me wonder if there are any exceptions, things that brains didn’t name. Onomatopoeia seem like a good starting place (and maybe ending place). Did we name cats’ meows meows or just hear them and go “OK, that’s what that is then”? Cat brains didn’t name them that either, they weren’t thinking what they should call the sound they make, they just made it.

As far as things which name themselves, I can’t think of anything else but sounds.