Grizzly bears are apex predators weighing up to 800 pounds, with claws and teeth evolved for killing. Wrestling a grizzly is considered suicidally dangerous. The fact poses the question—would Chuck Norris wrestle one?—and then pivots with a joke comparing the bear to Rosie O'Donnell. The punchline is not about Chuck Norris at all; it's a celebrity insult.

This reveals the construction of the joke: the actual content is secondary to the format. You could plug in any female celebrity and the mechanism would work. The bear becomes irrelevant. The joke isn't about wrestling skill; it's about comedic insult, about using the Chuck Norris framework to deliver a zinger at someone's appearance or public personality.

A talk show host, Rebecca Simmons, reviewed comedy submissions in 1994 and noticed that several riff on this structure—setup about Chuck Norris doing something dangerous, punchline insulting a specific celebrity. She noted that the format was popular but that the underlying mechanics were identical regardless of the target. She stopped programming these jokes because the audiences were laughing not at Chuck Norris but at the celebrity targets.

The joke exposes the variability and interchangeability of the Chuck Norris meme. He's not a consistent character; he's a punchline delivery system. You can construct him to say almost anything, and the beard, the legend, the cultural authority will carry it. The wrestling setup is just infrastructure for celebrity mockery.