1. Etymologically speaking, nightingale = night + yeller
2. yell = ululate (near enough)
3. "nightingale" is apparently not a species (surprised me, too) - just a motley bunch of birds that yell at night.
4. It follows that an owl [b}is a nightingale!
What a delightful piece of etymological Jesuitry! Have you ever read Lewis Carroll's critique of a new belfry erected at his Cambridge college? It uses a very similar sort of reasoning on etymology. It's very short, but very funny. I'm sure he would approve of your sophistry.
