Why do gorillas have such large nostrils?
Q: Why do gorillas have such large nostrils?
This is a very uncommon joke. I have only ever hear it from one source, and I don't know where she heard it from. This joke is in the category of toilet humor, as the joke centers around the idea of picking noses.
A: Because they have such large fingers.
The reason why it is funny is because the joke causes the hearer to consider why having a large finger would cause someone to have a large nostril. The conclusion that the hearer is supposed to come to is that the large fingered person would need a large nostril if the finger were supposed to be inserted into the nostril. It insinuates (but doesn't actually say) that gorillas pick their noses.