When I first heard this silly riddle, long ago, I thought it was funny in a subtle way:
QUESTION: What's the difference between a canary?
Listeners will ask, of course: Between a canary and what? But the question must remain exactly as is: What's the difference between a canary?
ANSWER: There's no difference whatsoever between a canary, because it has two legs of exactly the same length, the right one a little bit more than the left.
In the political domain, when two individuals seem to be advocating identical strategies, observers often say: bonnet blanc, blanc bonnet, which might be translated as "the bonnet is white, it's a white bonnet". In everyday English: "six of one and half a dozen of the other".
In colloquial French, there's a neat way of saying that two things are the same: C'est kif-kif. Apparently, kif is a Maghrib term meaning "the same", and French people have doubled the syllable in the belief that kif-kif sounds more Arabic.
Now, if you want to be long-winded about saying that two things are the same, you can add on a popular term for "donkey": C'est kif-kif bourricot. And what's the role of the donkey in this verbal construction? Well, it would appear that, in North Africa, to indicate that two things are the same, people often say that they're kif-kif... like a donkey. Like a canary, for that matter.