All these jokes have bunches of variants. The one I originally heard went
Speaker 1: What's green, hangs from a tree, and squeaks?
Speaker 2: I don't know. What's green, hangs from a tree, and squeaks?
S1: A herring.
S2: I don't get it.
S1: Can't you paint a herring green?
S2: Yes, but...
S1: Can't you hang a herring from a tree!
S2: Yes, but...
S1: So there you are!
S2: But what about the squeak?
S1: Oh, that was just to make it difficult!
Fap !!! And the ethnicity is totally irrelevant; substitute any name or class or stereotype you like and it changes nothing.
Some years ago there was a soft-porn low-resolution computer game called Leisure Suit Larry, followed by a small raft of sequels. One of the earlier scenes showed LSL in a bar listening to dialogue that went something like "blah-blah-blah ... [punchline of a dirty joke, like "Twenty dollars, same as in town!"] ... HAR-HAR-HAR! ... blah-blah-blah ... [punchline of another dirty joke, like "...'cause tonight's your night in the barrel!"] ... HAR-HAR-HAR! ... " until you/LSL did something to move the action along. They repeated at random, but there were at least 20 punchlines, maybe closer to forty. I was chagrinned (dare I say proud?) and a bit surprised to see how many of the jokes I could recognize from their punchlines. Apparently there is a finite set of jokes that have persisted and become virtually universal, and it's a considerably smaller number than I would have predicted.
