If it looks like duck

Tastes like chicken!

Imagining a sagey, elder Japanese man saying this makes it all the funnier. I think humor in senryu form is wonderful, because it creates a premise that this collection of syllables has to be serious and natural. For it to be a joke is the perfect punch line in and of itself.

Lol that's really true, it's not a chicken.
Nice us of repetition.