What kind of jokes are these? Where do they come from?

Q. “How many half eggs does it take to build a doghouse out of pancakes?”

A. “Dolphins don’t have finger nails!”

I’d call the device a non sequitur and the genre surreal (or absurdist) humour.

How many post-modernists does it take to subvert a prevailing paradigm?

I’m fond of the variant of non-sequitur humor, as practiced in Harvard Lampoon’s “Bored of the Rings,” or (for example) in the Sam & Max comic book.

“Trapped! Trapped like a ring-tailed rock wallaby!”

‘Trapped like beavers!’

To begin with, it isn’t even remotely a joke.

“The American Non Sequitur Society
We may not make sense, but we do like pizza.”

“Go not to the surrealists for counsel, for they will say both blue and hippopotamus.”

I call them nonsense jokes. They are similar in effect to what my son calls anti-jokes. The structure of the joke is different but it seems to hit the same humor spot.

My father called them Communist jokes. But then he’s old enough to have lived through all of the Cold War. I imagine it’s like my Grandfather and his love of “Polack” jokes, many of which have been rebranded as “blond” jokes now. Pick a group you don’t like and make up stupid jokes about them.

“What’s the difference between a duck’s leg?”

“None! It’s both the same.”

Yeah, they’re not quite the same thing as anti-jokes, but they’re maybe in the same ballpark.

Why is a duck?

Because one of both of its feet are the same.

No soap, radio!

The higher, the fewer!

Potato.

Isn’t that why the OP is asking about it?

It was a Thing when I was in high school: telling that type joke to Freshmen to get them to laugh along, so they could then be laughed at for laughing. Ah, those were the days.

“Q: How many pancakes does it take to get to the moon?
A: None, because ice cream has no bones!”

At the time, I kinda put them in the same category as Steve Martin’s approach to humor. Absurd, but funny if done well, because the act of delivering nonsense words using Joke pacing and tone can be meta-funny. But it can get old fast. I love Steve Martin, but there aren’t many like him, and he hasn’t flexed that muscle much in the past few decades.

So they work for Ausonia?

It’s the snipe hunt equivalent of a joke. It’s more like a practical joke than a genuine Q&A joke. You persuade the listener that there is something intuitive they are missing, or some convoluted Jeff Goldblum reasoning they can’t figure out, when it’s really just made up. It starts out sounding like one of those “If an electric train is going North, which way is the smoke going?” where if you search the question, you find the fault, and therefore the answer. If you get the victim to laugh at the joke, then you get a laugh at his expense.

Since it is in the form of a question and answer, it is a riddle, not a joke.

How many surrealists does it take to screw in a lightbulb?

Two: one to fill the bathtub with brightly-colored power tools, and the other to stroke the giraffe.

“You try to cross over there a chicken, and you’ll find out why a duck.” - Groucho

Ah yes, like “If a plane crashes on the border between France and Germany, where will they bury the survivors?” Running a misdirection play on the brain.